HTP EP-80 Elite Premier Residential and Commercial Boilers Instruction Manual

Instruction Manual for HTP models including: EP-80, EP-110, EP-150, EP-220, EP-299, EP-301, EP-399, Elite Premier Residential and Commercial Boilers

Elite Premier

Elite Premier - HTP

WHAT TO DO IF YOU SMELL GAS. • Do not try to light any appliance. • Do not touch any electrical switch; do not use any phone in your building.

Warranty

EP-80N Ariston Thermo USA LLC (HTP) | M&N Plumbing Supply Co

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lp-550

Elite Premier
Residential and Commercial Boilers

Installation

Start-Up

Maintenance

Parts

Warranty
EP-80 / 110 / 150 / 220 / 299 / 301 / 399 Models*
* "N" Denotes Natural Gas Operation "LP" Denotes Propane Gas Operation

Heat Exchanger Bears the ASME "H" Stamp

This manual must only be used by a qualified installer / service technician. Read all instructions in this manual before installing. Perform steps in the given order. Failure to do so could result in substantial property damage, severe personal injury, or death.

Improper installation, adjustment, alteration, service, or maintenance could void product warranty and cause property damage, severe personal injury, or death.
California Proposition 65 Warning: This product contains chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.

HTP reserves the right to make product changes or updates without notice and will not be held liable for typographical errors in literature.
NOTE TO CONSUMER: PLEASE KEEP ALL INSTRUCTIONS FOR FUTURE REFERENCE.

272 Duchaine Blvd.

New Bedford, MA 02745

www.htproducts.com LP-550 Rev. 000 Rel. 022 Date 4.2.21

2 WARNING: If the information in these instructions is not followed exactly, a fire or explosion may result causing property damage, personal injury or death.
· Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
· Do not try to light any appliance. · Do not touch any electrical switch; do not use any phone in your building. · Immediately call your gas supplier from a neighbor's phone. Follow the gas supplier's instructions. · If you cannot reach your gas supplier, call the fire department. · Installation and service must be provided by a qualified installer, service agency or the gas supplier. Improper installation, adjustment, alteration, service, or maintenance can cause injury, property damage, or death. Refer to this manual. Installation and service must be performed by a qualified installer, service agency, or gas supplier.
LP-550 Rev. 000 Rel. 022 Date 4.2.21

The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels or to important product information.
DANGER indicates an imminently hazardous situation which, if not avoided, will result in serious personal injury or death.
WARNING indicates a potentially hazardous situation which, if not avoided, could result in personal injury or death.

Installation should be made in accordance with the regulations of the Authority Having Jurisdiction, local code authorities, and utility companies which pertain to this type of water heating equipment.
Authority Having Jurisdiction (AHJ) The AHJ may be a federal, state, local government, or individual such as a fire chief, fire marshal, chief of a fire prevention bureau, labor department or health department, building official or electrical inspector, or others having statutory authority. In some circumstances, the property owner or his/her agent assumes the role, and at government installations, the commanding officer or departmental official may be the AHJ.
NOTE: HTP reserves the right to modify product technical specifications and components without prior notice.

CAUTION indicates a potentially hazardous situation which, if not avoided, may result in moderate or minor personal injury.
CAUTION used without the safety alert symbol indicates a potentially hazardous situation which, if not avoided, may result in property damage.
NOTICE is used to address practices not related to personal injury.
Foreword
This manual is intended to be used in conjunction with other literature provided with the boiler. This includes all related control information. It is important that this manual, all other documents included in this system, and additional publications including the National Fuel Gas Code - ANSI Z223.1 (latest versions), be reviewed in their entirety before beginning any work.

For the Installer
This boiler must be installed by qualified and licensed personnel. The installer should be guided by the instructions furnished with the boiler, and by local codes and utility company requirements. In the absence of local codes, preference should be given to the National Fuel Gas Code - ANSI Z223.1 in the United States and the Natural Gas and Propane Installation Code - B149.1 in Canada (latest versions).
Installations Must Comply With: Local, state, provincial, and national codes, laws, regulations, and ordinances.
The latest version of the National Fuel Gas Code, ANSI Z223.1, from American Gas Association Laboratories, 8501 East Pleasant Valley Road, Cleveland, OH 44131.
The latest version of the National Electrical Code, NFPA No. 70.
In Canada - The latest versions of the Natural Gas and Propane Installation Code, CSA B149.1, and the Canadian Electrical Code, C22.1, from CSA Group, 178 Rexdale Blvd, Toronto, Ontario, Canada M9W 1R3.
NOTE: The gas manifold and controls met safe lighting and other performance criteria when undergoing tests specified in ANSI Z21.13 - latest edition.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

The hydronic supply and return connections of these products are for installation in closed loop systems ONLY! Use of this product in any manner other than described in this manual may result in premature product failure, substantial property damage, severe personal injury, or death. Damage or failure of this product (or the system in which it is installed) due to unauthorized use IS NOT COVERED BY WARRANTY.
IMPORTANT In accordance with Section 325 (f) (3) of the Energy Policy and Conservation Act, HTP has provided this boiler with multiple features designed to save energy by reducing the boiler water temperature as heating load decreases. These features include:
· A modulating combustion system that adjusts firing rate based on heat demand.
· Adjustment of boiler set point based on inferred heat load as determined by an outdoor sensor. The outdoor sensor is supplied by HTP with this boiler.
· This boiler does not include a standing pilot. · This boiler is designed and shipped to assure the highest
efficiency operation possible. Such high efficiency is achieved by limiting heating circuit water temperature to 140°F when there is no anticipated heat load, based upon the outdoor sensor and the Outdoor Reset Curve (sensor response curve) in the boiler software. · This feature may be over-ridden as described below in specific installations: · The boiler control is equipped with an outdoor sensor override for use with building management systems or in cascaded systems (for systems with total input of 300,000 BTU/hr or greater). See statement below for an important notice on the use of the override.
IMPORTANT In accordance with Section 325 (f) (3) of the Energy Policy and Conservation Act, this boiler is equipped with a feature that saves energy by reducing the boiler water temperature as the heating load decreases. This feature is equipped with an override which is provided primarily to permit the use of an external energy management system that serves the same function. THIS OVERRIDE MUST NOT BE USED UNLESS AT LEAST ONE OF THE FOLLOWING CONDITIONS IS TRUE:
· An external energy management system is installed that reduces the boiler water temperature as the heating load decreases.
· This boiler is not used for space heating. · This boiler is part of a modular or multiple boiler system
having a total input of 300,000 BTU/hr or greater. · This boiler is equipped with a tankless coil.
LP-550 Rev. 000 Rel. 022 Date 4.2.21

The CSD-1 ASME Code, Section CW-400 requires that hot water heating and supply boilers have a) a UL 353 temperature control device, b) at least one (1) temperature-actuated control to shut off the fuel supply when system water reaches a preset operating temperature, c) a high temperature limit control that prevents the water temperature from exceeding the maximum allowable temperature by causing a safety shutdown and lockout, and d) its own sensing element and operating switch. The temperature control system integrated into the 928 control provided with this heating appliance complies with the requirements of CSD-1 Section CW-400 as a temperature operation control. The control monitors the temperature difference between the inlet and the outlet sensor, which is affected by boiler water flow. If this temperature difference exceeds 55°F (typically because of low water flow or very low heat load), the control will reduce the maximum fan speed. If the temperature difference exceeds 60°F, the control will effectively sense there is little or no water flow or heat load and shut the boiler down. The controller will restart automatically once the temperature difference has dropped below 55°F and the minimum off time (anti-cycle time) has expired. In addition, if the control senses that the outlet water temperature has reached 210°F, the boiler is put into a hard lockout and requires manual reset to restart.

Table of Contents

Part 1 - General Safety Information

A. Operation and Installation Warnings

B. Improper Combustion

C. Gas

D. When Servicing the Boiler

E. Boiler Water

F. Water Chemistry Requirements*

G. Freeze Protection

H. Scalding

I. High Elevation Installations

Part 2 - Before You Start

A. What's in the Box

B. How the Boiler Operates

C. Optional Equipment

Part 3 - Prepare the Boiler

A. Locating the Boiler

B. Flooring

C. Leveling

D. Clearances for Service Access

E. Residential Garage and Closet Installations

F. Exhaust Vent and Intake Pipe

1. Direct Vent of Exhaust and Intake

2. Power Venting, Indoor Combustion Air in Confined or Unconfined

Space

G. Carbon Monoxide Detectors

H. Prevent Combustion Air Contamination

I. Removing a Boiler from a Common Vent System

J. Technical Specifications

Part 4 - Piping

A. General Plumbing Information

B. Relief Valve

C. Backflow Preventer

D. Expansion Tank

E. Circulators

F. Hydronic Piping with Circulators, Zone Valves, and Multiple Boil-

ers

G. Circulator Sizing

H. Check / Control Water Chemistry

I. Plumbing

J. Fill and Purge Heating System

K. Freeze Protection Fluids

L. Zoning with Zone Valves

M. Zoning with Circulators

N. Multiple Boilers

O. Applications*

Part 5 - Venting

A. General

B. Approved Materials for Exhaust Vent and Intake Pipe

C. Additional Requirements for Installation in Canada

D. Exhaust Vent and Intake Pipe Location

E. Exhaust Vent and Intake Pipe Sizing

F. Longer Vent Runs

G. Exhaust Vent and Intake Pipe Installation

H. Applications

1. Direct Vent Installation of Exhaust and Intake

2. Venting Through an Existing System

3. Power Venting, Indoor Combustion Air in Confined or Unconfined

Space

Part 6 - Condensate Removal

Part 7 - Wiring

A. Installation Must Comply With

B. Field Wiring Terminations

C. Field Wiring

D. Line Voltage Wiring for Standard Boiler

E. Alarm Connections

F. Low Voltage Connections for Standard Boiler

G. Thermostat

H. Outdoor Sensor

I. Indirect Sensor

J. Optional 0-10 Volt Building Control Signal

K. Optional Low Water Cut-Off (LWCO) Kit

L. Wiring of Cascade System Communication Bus

M. Cascade Master Pump and Sensor Wiring

N. Cascade Follower Pump and Sensor Wiring

O. Variable Speed Pumping

Part 8 - Gas Connections

A. Gas Piping

B. Additional Precaution for Excess Flow Valve (EFV)

C. Check Inlet Gas Pressure

D. Boiler Gas Valve

Part 9 - Start-Up Preparation

A. Check / Control Water Chemistry

B. Check for Gas Leaks

C. Freeze Protection (When Used)

D. Fill and Test Water System

E. Purge Air from Water System

F. Check Thermostat Circuit(s)

G. Condensate Removal

H. Final Checks Before Starting Boiler

I. Setting Up a Single Boiler

J. Setting Up a Cascaded System

K. Lockout Condition

L. Cascade System Programming

Part 10 - Start-Up Procedure

A. Control Overview

B. Navigation of the Display

C. Operating Instructions

D. Programming Boiler Settings

E. Programming the System Setting

F. System Setting Program Navigation

G. Resetting the Maintenance Schedule

Part 11 - Start-Up Procedures for the Installer

A. Boiler Control Status Menu

B. Cascade Menu

C. Boiler Test Mode

Part 12 - Troubleshooting

A. Boiler Error and Fault Codes

B. Boiler Error

C. Boiler Fault

D. User Interface Display

Part 13 - Maintenance

A. Procedures

B. Combustion Chamber Coil Cleaning Instructions

C. Cleaning Water Side of Heat Exchanger

D. Maintaining the Condensate System

Part 14 - Installation Checklist

Part 15 - Maintenance Report

Part 16 - Replacement Parts

Limited Warranty

Maintenance Notes

Customer Installation Record Form

Part 1 - General Safety Information
This boiler is approved for indoor installations only and is not intended for use as a pool heater. Clearance to combustible materials: 0" top, bottom, sides, and back. Left side has all boiler mechanical connections. Boiler must have room for service: 24" front is minimum recommended service clearance. (A combustible door or removable panel is acceptable front clearance.) This boiler has been approved for closet installation and installation on combustible flooring. Do not install directly on carpeting. Install the boiler in a location where temperature and pressure relief valve discharge or a leak will not result in damage to the surrounding area. If such a location is not available, install an auxiliary catch pan.
This appliance is rated Category IV (pressurized vent, likely to form condensate in the vent) and requires a special vent system designed for pressurized venting. Use only Category IV vent systems.

Installer - Read all instructions in this manual before installing. Perform steps in the given order.
User - This manual is for use only by a qualified heating installer / service technician. Have this boiler serviced / inspected annually by a qualified service technician.
FAILURE TO ADHERE TO THE GUIDELINES ON THIS PAGE CAN RESULT IN SUBSTANTIAL PROPERTY DAMAGE, SEVERE PERSONAL INJURY, OR DEATH.
NOTE: Obey all local codes. Obtain all applicable permits before installing the boiler.
NOTE: Install all system components and piping in such a manner that does not reduce the performance of any fire rated assembly.
A. Operation and Installation Warnings To avoid serious injury or death, read, understand, and follow all of the precautions listed here.
! DANGER
Vapors from flammable liquids will explode and cause a fire, resulting in personal injury or death. The boiler has a burner that can come on at any time and ignite vapors. DO NOT use or store flammable liquids around the boiler. Improper venting can cause a build-up of carbon monoxide. Breathing carbon monoxide can result in brain damage or death. DO NOT operate the boiler unless it is properly vented to the outside and has an adequate fresh air supply for safe operation. Inspect the exterior exhaust gas outlet port and fresh air inlet port on a regular basis to ensure they are functioning properly.
Failure to follow these instructions will result in property damage, severe personal injury, or death.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

! DANGER
A concentration of carbon monoxide as small as .04% (400 parts per million) in the air can be fatal. When making high fire or low fire adjustments, CO levels must be monitored using a calibrated combustion analyzer such that a CO level of no more than 150 ppm is exceeded at any time during operation.
Adjusting the "low fire offset" or the "main flow restrictor" in small increments can result in a significant increase in CO concentration. To avoid serious injury or death, DO NOT make any adjustments to the gas valve without monitoring the exhaust gases with a fully functional and calibrated combustion analyzer.
Failure to follow these instructions will result in property damage, severe personal injury, or death.
! WARNING
This boiler must be installed by a qualified service technician. Improper installation and/or operation can cause a potentially hazardous situation, which if not avoided will void the warranty and could result in serious injury or death.
The manufacturer cannot anticipate every circumstance that might involve a potential hazard. Each installation has its own specialized characteristics, requirements, and possible hazards. Therefore, all possible incidents are not included in these warnings. Proper and safe installation, operation, and service are the responsibility of the qualified service technician.
Proper care of the boiler is the user's responsibility. Ensure the user carefully reads and understands the User's Information Manual before operating the boiler.
Make sure the user knows the location of the gas shut-off valve and how to operate it. Immediately close the gas shut-off valve if the appliance is subjected to fire, overheating, flood, physical damage, or any other damaging condition that might affect the operation of the unit. Have the appliance checked by a qualified service technician before resuming operation.
Do not power up the unit unless the gas and water supply valves are fully opened. Make sure the fresh air intake port and exhaust gas port are open and functional.
No one but a qualified service technician should attempt to install, service, or repair this boiler. There are no serviceable parts which can be changed by the user / owner.
User / Owner: Contact the original qualified service technician if the boiler needs repair / maintenance. If the original technician is unavailable, ask your gas supplier for a list of qualified service providers.
DO NOT store or place newspapers, laundry, or other combustible items near the appliance or the exterior exhaust gas outlet and/or fresh air inlet port.
The owner should inspect the system monthly for damage, water stains, signs of rust, corrosion, and exhaust vent and air intake blockage. If inspection of the unit shows signs of damage, the boiler should be shut off until the problem is repaired by a qualified technician.
After installation, all appliance safety devices should be tested.
The boiler is certified for indoor installations only. The boiler consists of gas ignition system components which must be protected from water (dripping, spraying, etc.) during operation and service. Carefully consider installation location and the placement of critical components (circulators, condensate neutralizers, etc.) before installing the boiler.
DO NOT allow children to operate this boiler. DO NOT use this boiler if it does not appear to be operating correctly. A qualified service technician should service and inspect the boiler annually.

! WARNING
NOTE: If the boiler is exposed to fire or water (or is any way damaged), do not operate. Immediately call a qualified service technician. Failure to follow this information could result in property damage, severe personal injury, or death.
DO NOT USE THIS BOILER IF ANY PART HAS BEEN SUBMERGED IN WATER. Immediately call a qualified service technician. The boiler MUST BE replaced if it has been submerged. Attempting to operate a boiler that has been submerged could create numerous harmful conditions, such as a potential gas leakage causing a fire and/or explosion, or the release of mold, bacteria, or other harmful particulates into the air. Operating a previously submerged boiler could result in property damage, severe personal injury, or death. NOTE: Boiler damage due to flood or submersion is considered an Act of God, and IS NOT covered under product warranty.
DO NOT alter or modify the appliance or appliance controls. Altering any HTP boiler with parts not manufactured by HTP WILL INSTANTLY VOID the boiler warranty and could result in property damage, personal injury, or death.
CAUTION
Due to low water content of the boiler, improperly sizing the boiler in regard to heating load will result in excessive boiler cycling and accelerated component failure. HTP DOES NOT warrant failures caused by improperly sized boiler applications. DO NOT oversize the boiler to the system. Modular boiler installations greatly reduce the likelihood of boiler oversizing. High heat sources (sources generating heat 100oF / 37oC or greater, such as stove pipes, space heaters, etc.) may damage plastic components of the boiler as well as plastic vent pipe materials. Such damages ARE NOT covered by warranty. It is recommended to keep a minimum clearance of 8" from high heat sources. Observe heat source manufacturer instructions, as well as local, state, provincial, and national codes, laws, regulations and ordinances when installing this boiler and related components near high heat sources.
Do not use this boiler for anything other than its intended purpose (as described in this manual). Doing so could result in property damage and WILL VOID product warranty.
NOTICE
This appliance provides an overheat shutdown limit. In the event the appliance water temperature exceeds the setpoint of the control limit, the cutoff will trip and the appliance will shut down. Certain local codes require additional temperature limits. In addition, certain types of systems may operate at temperatures below the minimum setpoint of the limit provided with the appliance. Contact the manufacturer for additional overheat controls.
B. Improper Combustion
! WARNING
Do not obstruct the flow of combustion and ventilating air. Adequate air is necessary for safe operation. Failure to keep the exhaust vent and combustion air intake clear of ice, snow, or other debris could result in property damage, serious personal injury, or death.
C. Gas Should overheating or gas supply fail to shut off, turn off the manual gas control valve to the boiler.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

D. When Servicing the Boiler
! WARNING
Be sure to disconnect electrical power before opening boiler cabinet or performing service. Label all wires while performing service to ensure proper re-wiring of the appliance. Wiring errors can cause improper or dangerous operation. Failure to do so could result in electrical shock, improper boiler or system operation, property damage, serious personal injury, or death.
· To avoid electric shock, disconnect electrical supply before performing maintenance.
· To avoid severe burns, allow boiler and associated equipment to cool before servicing.
· Do not use petroleum-based cleaning or sealing compounds in boiler system. Gaskets and seals in the system may be damaged, possibly resulting in substantial property damage.
· Do not use "homemade cures" or "boiler patent medicines". Substantial property damage, damage to boiler, and/or serious personal injury may result.
· Always verify proper operation after servicing the boiler.
NOTE: When inquiring about service or troubleshooting, reference the model and serial numbers from the boiler rating label.
E. Boiler Water · Thoroughly flush the system (without the boiler connected) to remove sediment. The high-efficiency heat exchanger can be damaged by build-up or corrosion due to sediment. The manufacturer recommends a suction strainer in this type of system.
· Do not use petroleum-based cleaning or sealing compounds in boiler system. Gaskets and seals in the system may be damaged, possibly resulting in substantial property damage.
· Do not use "homemade cures" or "boiler patent medicines". Substantial property damage, damage to the boiler, and/or serious personal injury may result.
· Continual fresh make-up water will reduce boiler life. Mineral buildup in the heat exchanger reduces heat transfer, overheats the stainless steel heat exchanger, and causes failure. Addition of oxygen from make-up water can cause internal corrosion in system components. Leaks in the boiler or piping must be repaired at once.
NOTE: DO NOT add cold make up water to the system when the boiler is hot. Thermal shock can potentially cause cracks in the heat exchanger. Such damage IS NOT covered by warranty.
F. Water Chemistry Requirements*
! WARNING
Chemical imbalance of the water supply may affect efficiency and cause severe damage to the appliance and associated equipment. It is important that the water chemistry on both the domestic hot water and central heating sides are checked before installing the appliance. Water quality must be professionally analyzed to determine whether it is necessary to treat the water. Various solutions are available to adjust water quality. Adverse water quality will affect the reliability of the system. In addition, operating temperatures above 135oF will accelerate the build-up of lime scale and possibly shorten appliance service life. Failure of an appliance due to lime scale build-up, low pH, or other chemical imbalance IS NOT covered by the warranty.
Closed loop water must be free of corrosive chemicals, sand, dirt, and other contaminates. It is up to the installer to ensure the water does not contain corrosive chemicals or elements that can damage

the heat exchanger.
If you suspect that your water is contaminated in any way, discontinue use of the appliance and contact an authorized technician or licensed professional.
· Water pH between 6.5 and 8.5 · pH levels below 6.5 can cause an increase in the rate of corrosion. pH of 8.5 or higher can potentially cause lime scale build-up
· Maintain water pH between 6.5 and 8.5. Check with litmus paper or have it chemically analyzed by a local water treatment company.
· If the pH is not between 6.5 and 8.5, consult a local water treatment company for solutions.
· Hardness less than 7 grains (120 mg/L) (Water temperatures of 140oF and greater) · Hardness levels above the required amounts can lead to lime scale build-up throughout the system. Water below 5 grains/ gallon (85 mg/L) may be over softened.
· Consult local water treatment companies for unusually hard water areas (above the required amounts) or for other treatment solutions if water is being over softened (below 5 grains/gallon [85 mg/L]).
· Chloride concentration less than 100 ppm (mg/L) · Do not fill appliance or operate with water containing chlorides in excess of 100 ppm (mg/L).
· Using chlorinated fresh water should be acceptable as levels are typically less than 5 ppm (mg/L).
· Do not connect the appliance to directly heat swimming pool or spa water.
· Total Dissolved Solids (TDS) less than 500 ppm (mg/L) · Total dissolved solids are minerals, salts, metals, and charged particles that are dissolved in water.
· The greater the amounts of TDS present, the higher the corrosion potential due to increased conductivity in the water.
· If using softened water to fill the appliance, it is still possible to have high TDS. This water can be corrosive. Consult local water treatment companies for other treatment solutions to reduce this effect.
*NOTE: It is recommended to clean the heat exchanger at least once a year to prevent lime scale buildup. To clean the heat exchanger, follow the maintenance procedure in this manual.
WATER CHEMISTRY NOTES:
1. Avoid exposing the heat exchanger water tubes to oxygen to prevent internal corrosion. System leaks and continuous make-up water will introduce oxygen into the system, increasing the opportunity for internal corrosion and possibly reducing the life of the heat exchanger and system components.
2. Leaks in the boiler or piping must be repaired at once to prevent excessive make-up water. It is recommended to install a water meter to regularly check the amount of make-up water entering the system. Make-up water volume should not exceed 5% of the total system volume per year. When make-up water is added, ensure chemical additives (glycol, corrosion inhibitors, etc.) are added to maintain the correct level.
3. Regularly monitoring pH, chlorides, TDS, and hardness levels can prolong the life of the appliance by reducing mineral scale buildup, corrosion, and erosion. Mineral buildup in the heat exchanger reduces heat transfer, overheats the stainless steel heat exchanger, and causes failure.
4. A corrosion inhibitor approved for use with stainless steel heat

LP-550 Rev. 000 Rel. 022 Date 4.2.21

exchangers (comparable to Sentinel X100 or Fernox F1) is recommended at the correct concentration and in the manner recommended by the manufacturer.heat exchangers (comparable to Sentinel X100 or Fernox F1) is recommended at the correct concentration and in the manner

Table 1 details the relationship of water temperature and time with regard to scald injury and may be used as a guide in determining the safest water temperature for your applications.

G. Freeze Protection
CAUTION
Consider piping and installation when determining boiler location. Damages resulting from incorrect installation or from use of products not approved by the manufacturer ARE NOT covered by warranty. Failure of the boiler due to freeze related damage IS NOT covered by product warranty.
! WARNING
NEVER use any toxic chemical, including automotive, standard glycol antifreeze, or ethylene glycol made for hydronic (non-potable) systems. These chemicals can attack gaskets and seals in water systems, are poisonous if consumed, and can cause personal injury or death.
NOTE: Loops Serving Indirect Water Heaters (IWHs)
Glycol used in IWH loops should be food grade propylene glycol, FDA rated as "generally recognized as safe" (GRAS). If using a glycol / potable water mix, the water chemistry must meet the requirements in this manual. The glycol content of the liquid must not exceed 50%, unless the manufacturer specifies a different ratio. Glycol should be checked periodically to prevent it from becoming acidic. Please refer to guidelines provided by the glycol manufacturer regarding glycol maintenance.
NOTE: Glycol not recognized as GRAS may only be used in closed loop CH applications.
NOTE: HTP DOES NOT WARRANT THE BOILER AGAINST FREEZERELATED DAMAGE.
The boiler control is equipped with freeze protection that activates based on internal water temperature. NOTE: Freeze protection will not be active if the boiler loses power.
H. Scalding Boilers Serving Indirect Water Heaters
This boiler can deliver scalding water to the indirect water heater. Be careful whenever using hot water to avoid scalding injury. Certain appliances such as dishwashers and automatic clothes washers may require increased water temperatures. By setting the thermostat on this boiler or the indirect water heater to obtain the increased water temperature required by these appliances you may create the potential for scald injury.
To protect against injury, install a mixing valve in the water system. This valve will reduce point of use discharge temperatures by mixing cold and hot water in branch supply lines. Such valves are available from your local plumbing supplier.

The risk of scalding increases when raising DHW temperature. Use a water tempering or mixing valve when raising DHW temperature to lessen the chance of scalds. Consult codes for conformance. Failure to install a temperature limiting or mixing valve and follow these instructions could result in property damage, severe personal injury, or death due to scalds.
Approximate Time / Temperature Relationships in Scalds

120oF 125oF 130oF

More than 5 minutes 1 1/2 to 2 minutes About 30 seconds

135oF 140oF 145oF

About 10 seconds Less than 5 seconds Less than 3 seconds

150oF

About 1 1/2 seconds

155oF

About 1 second

Table 1 - Approximate Time / Temperature Relationships in Scalds

I. High Elevation Installations This boiler is designed to operate at its maximum listed capacity in installations located at 0 - 2000 ft above Sea Level. Since the density of air decreases as elevation increases, maximum specified capacity should be de-rated for elevations above 2000 ft (610 m) in accordance with the table below.

Elevations
In Canada1, de-rate by: In USA2, de-rate by:

2001 ft 3000 ft 4000 ft 4500 ft 5000 ft (610 m) (914 m) (1219 m) (1372 m) (1524 m)

10%

10% may vary

12%

16%

18%

20%

NOTES: 1Canada: Elevations between 2000 - 4500 ft (610 - 1372 m), de-rate by 10%. Consult local authorities for de-rating for elevations above 4500 ft (1372 m). 2USA: If elevation is above 2000 ft (610 m), de-rate capacity by 4% for every 1000 ft (305 m).
Table 2 - De-Rate % for High Elevations

! WARNING
Combustion - At elevations above 2000 ft, the combustion of the boiler must be checked with a calibrated combustion analyzer to ensure safe and reliable operation. It is the Installer's responsibility to check and adjust the combustion in accordance with this manual. Failure to follow these instructions may result in property damage, serious personal injury, or death.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 2 - Before You Start
NOTICE
UNCRATING THE BOILER - Any claims for damage or shortage in shipment must be filed immediately against the transportation company by the consignee.
Remove the boiler and accessories from the shipping crate. Take care to place the boiler and accessories in a safe location prior to installation to prevent damage to the mechanical connections.
A. What's in the Box Components (and Part #) included with the boiler:
· Temperature and Pressure Gauge (7500P-098) · Pressure Relief Valve (7250P-080) · Indirect Sensor (7250P-325) · Outdoor Sensor (7250P-319) · Intake PVC Tee with Screens · Exhaust PVC Coupling with Screens · Outlet Combination Fitting (80/110/150/220 Models - 7450P-
134, 299/301 Models - 7450P-135, 399 Model - 7450P-136) · Installation Manual and Warranty · CSD-1 Form · H-3 Data Sheet
B. How the Boiler Operates Condensing technology intelligently delivers hydronic heating while maximizing efficiency. Outlined below are the features of the system and how they operate: Stainless Steel Heat Exchanger The highly efficient stainless steel heat exchanger is designed to extract all available heat from the supply line before it is exhausted. Modulating Combustion System The combustion system modulates the output of the burner during operation to match system demand and achieve the control set point while in operation. The set point can change by internal or external signals to enhance the overall performance of the system. Control The integrated control system monitors the system and regulates fan speed to control boiler output. This allows the boiler to deliver only the amount of heat energy required and nothing more. The control can be set to monitor outdoor temperature through an outdoor sensor to regulate boiler set point. The system can be further enhanced by installing an indirect water heater to provide domestic hot water. The control can regulate the output of multiple boilers through its cascade system function. The cascade system is capable of connecting up to eight boilers together in such a way that they function as one boiler system. This allows for greater turn down ratios and provides systematic control of the multiple boilers in an installation to minimize downtime and maximize efficiency. The cascade system works by establishing one boiler as the master and the other connected boilers as followers. The master boiler requires a sensor to provide feedback on set point temperature in order to adjust heating input from the connected boilers. Each cascaded boiler will have its own pump to provide maximum flow and control heat exchanger flow rate. Text Display and Operational LED Light Indicators The display allows the user to change system parameters and monitor system outputs. Gas Valve Senses suction from the blower, allowing gas to flow only if powered and combustion air is flowing. All Metal Integrated Venturi Controls air and gas flow into the burner.

Burner The high grade stainless steel burner uses premixed air and gas to provide a wide range of firing rates. Spark Ignition The burner is ignited by applying high voltage through the system spark electrode. The spark from the electrode ignites mixed gas off of the burner. Dual Supply Water Temperature Sensor / High Limit Water ECO This dual sensor monitors the boiler outlet water temperature (System Supply). The control adjusts boiler firing rate so the supply temperature will match the boiler set point. The dual sensor meets all requirements to function as a safety, eliminating the mechanical ECO and increasing safety and reliability. Return Water Temperature Sensor This sensor monitors boiler return water temperature (System Return). Flue Sensor Monitors flue temperature and adjusts firing rate. Temperature and Pressure Gauge Allows the user to monitor system temperature and pressure. Electrical field connections with terminal strips The electrical cover allows easy access to the clearly marked line voltage and low voltage terminal strips to facilitate wiring the boiler. Condensate Collection System This boiler is a high efficiency appliance and will produce condensate. The condensate collection system has a float which monitors condensate level and prevents condensate from backing up into the combustion system. Inside the collection system is a built in trap which seals the combustion system from the connected drain. This condensate should be neutralized to avoid damage to the drainage system or piping. Outdoor Sensor Monitors outdoor temperature and adjusts unit set point to provide greater efficiency. Indirect Tank Sensor Monitors storage tank temperature. 0-10 Volt Input Allows the installer to connect a BMS (Building Management System) to control the boiler. 0-10 Volt Output A (Configured through Control System) 0-10 Volt Output A is configured through the boiler's control system. 0-10 Volt Output A is related to one of the following boiler values: boiler power, cascade power, fan speed, alarm status, or temperature setting based on outdoor reset curve. UL 353 Internal Low Water Cutoff (LWCO) The supplied internal Low Water Cutoff meets UL 353 requirements to function as a safety, locking out the boiler when water level is inadequate for safe operation. To test LWCO function, press and hold v and RESET simultaneously for five (5) seconds. Press RESET to clear the error code. Boost Timer Function This function temporarily overrides the outdoor reset curve in order to satisfy a thermostat setpoint in a short amount of time, especially during a relatively warm day. Flue Temperature Modulation As an additional safety feature, if the flue temperature exceeds 200oF, the control will modulate the boiler down based on the vent temperature, rather than the supply temperature. If the flue temperature exceeds 210oF the control will lock out the boiler. System Sensor (Optional) This sensor is designed to be used in a cascade system. The system pipe sensor measures the temperature of return water and communicates with the control system to modulate the firing rate of the connected boilers. NOTE: When using a system sensor, pipe insulation must be wrapped around it to improve temperature measurement accuracy and increase overall system efficiency.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

External Low Water Cutoff (Optional) Connection points are provided on the Field Connection Board to install an external LWCO if required by local codes. Condensate Flue Check System The check system prevents heat exchanger exhaust from backing up into the cabinet. Pump Service Mode Allows manual operation of pumps to commission system and check pump operation.

Part 3 - Prepare the Boiler
Remove all sides of the shipping crate to allow the boiler to be moved into its installation location. The boiler is also equipped with leveling feet that can be used to level the boiler properly on an uneven location surface. If surface flooring is rough, take care when moving the boiler into position, as catching the leveling feet could damage the boiler.

C. Optional Equipment Optional equipment available from HTP (and Part #):
· Wall Mount Bracket (7450P-211) · System Sensor (7250P-324) · 3" Stainless Steel Vent Termination Kit (V1000) · 4" Stainless Steel Vent Termination Kit (V2000) · 6" Stainless Steel Vent Termination Kit (V3000) · 2" PVC Concentric Vent Kit (KGAVT0501CVT) · 3" PVC Concentric Vent Kit (KGAVT0601CVT) · 3" Polypro Vent Kit (8400P-001) · 3" Polypro Pipe
(33' length # 8400P-002, 49.5' length # 8400P-003) · Low Water Cut-Off Kit (7450P-904) · Manual Reset High Limit (7450P-910) · Alarm System (to monitor any failure) (7350P-602) · 928 PC Connection Kit with Software (7450P-330) · Condensate Neutralizer (80/110/150/220/299/301 Models -
7450P-212, 399 Model - 7350P-611) · Condensate Removal Pump (554200) · Flow Switch Kit (80/110/150/220 Models - 7450P-213, 299/301
Models - 7450P-214, 399 Model - 7450P-215) NOTE: When using an optional system sensor, pipe insulation must be wrapped around it to improve temperature measurement accuracy and increase overall system efficiency.

COLD WEATHER HANDLING - If the boiler has been stored in a very cold location (BELOW 0oF) before installation, handle with care until the components come to room temperature. Failure to do so could result in damage to the boiler. Carefully consider installation when determining boiler location. Please read the entire manual before attempting installation. Failure to properly take factors such as boiler venting, piping, condensate removal, and wiring into account before installation could result in wasted time, money, and possible property damage and personal injury.
A. Locating the Boiler
This boiler is certified for indoor use only. DO NOT INSTALL OUTDOORS. Outdoor installations ARE NOT covered by warranty. Failure to install the boiler indoors could result in property damage, severe personal injury, or death.
Incorrect ambient conditions can lead to damage to the heating system and put safe operation at risk. Ensure that the installation location adheres to the information included in this manual. Failure to do so could result in property damage, serious personal injury, or death. Failure of boiler or components due to incorrect operating conditions IS NOT covered by product warranty.

This boiler must be installed upright in the vertical position as described in this manual. DO NOT attempt to install this boiler in any other orientation. Doing so will result in improper boiler operation and property damage, and could result in serious personal injury or death.

This boiler has a condensate disposal system that may freeze if exposed to sustained temperatures below 32oF. Precautions should be taken to protect the condensate trap and drain lines from sustained freezing conditions. Failure to take precautions could result in property damage, severe personal injury, or death.

1. Installation Area (Mechanical Room) Operating Conditions · Ensure ambient temperatures are higher than 33oF / 0.6oC and lower than 104oF / 40oC · Prevent the air from becoming contaminated by the products, places, and conditions listed in this manual · Avoid continuously high levels of humidity · Never close existing ventilation openings · Ensure a minimum 1" clearance around hot water and exhaust vent pipes · NOTE: To prevent condensing in the fan, it is recommended to avoid prolonged exposure to temperatures below 45oF
2. Check for nearby connections to: · System water piping · Venting connections · Gas supply piping · Electrical power · Condensate drain

LP-550 Rev. 000 Rel. 022 Date 4.2.21

3. Check area around boiler. Remove any combustible materials, gasoline, and other flammable liquids.

B. Flooring

Failure to keep the boiler area clear and free of combustible materials, liquids, and vapors can result in substantial property damage, severe personal injury, or death.
The service life of the boiler's exposed metallic surfaces, such as the casing, as well as internal surfaces, such as the heat exchanger, are directly influenced by proximity to damp and salty marine environments. In such areas higher concentration levels of chlorides from sea spray coupled with relative humidity can lead to degradation of boiler components. In these environments, boilers must not be installed using direct vent systems which draw outdoor air for combustion. Such boilers must be installed using room air for combustion. Indoor air will have a much lower relative humidity, and hence potential corrosion will be minimized. High heat sources (generating heat 100oF / 37oC or greater, such as boiler flue pipes, space heaters, etc.) may damage plastic components of the boiler as well as plastic vent pipe materials. Such damages ARE NOT covered by warranty. It is recommended to keep a minimum clearance of 8"from high heat sources. Observe heat source manufacturer instructions, as well as local, state, provincial, and national codes, laws, regulations, and ordinances when installing this boiler and related components near high heat sources.
Gas conversion should be performed BEFORE the boiler is installed. Carefully follow the gas conversion instructions when performing the conversion. Failure of the boiler or components due to incorrect operating conditions IS NOT covered by product warranty. Always take future maintenance into consideration when locating the boiler. If the boiler is located in an installation location with limited clearances, it may be necessary to remove the boiler from the space to perform maintenance. Failure to consider maintenance when determining installation location could result in property damage.
4. Gas control system components must be protected from dripping water during operation and service.
5. If the boiler is to replace an existing boiler, check for and correct any existing system problems, such as:
· System leaks
· Location that could cause the system and boiler to freeze and leak
· Incorrectly sized expansion tank
6. Clean and flush system when reinstalling a boiler.
NOTE: When installing in a zero clearance location, it may not be possible to read or view some product labeling. It is recommended to make note of the boiler model and serial number.

Assure that the floor and structure of the installation location are sufficient to support the full installed weight of the boiler, including water content of the heat exchanger and related piping. Failure to ensure the floor and structure of the installation location are structurally sound before installation of the boiler can result in structural failure, substantial property damage, severe personal injury, or death. This boiler is approved for installation on combustible flooring, but must never be installed on carpeting. Installing this boiler on carpeting could result in fire, property damage, severe personal injury, or death. C. Leveling
In order for the condensate to properly flow out of the collection system, the area where you locate the boiler must be level. Location must also fully support the weight of the filled boiler.
Figure 1 - Correct and Incorrect Leveling
D. Clearances for Service Access NOTE: If you do not provide the minimum clearances shown in Figure 2 it might not be possible to service the boiler without removing it from the space.

Do not mount the boiler to a hollow wall. Mount to the studs only. Use extreme care not to drop the boiler or cause bodily injury while lifting or mounting the boiler onto the optional wall mount bracket. Failure to follow these instructions could result in property damage, severe personal injury, or death.
Figure 2 - Recommended Service Clearances

LP-550 Rev. 000 Rel. 022 Date 4.2.21

E. Residential Garage and Closet Installations

All boilers eventually leak. Locate the boiler where any leakage from the relief valve, related piping, tank, or connections will not result in damage to surrounding areas or lower floors of the building. Any boiler should be installed in such a manner that if it should leak the resulting flow of water will not cause damage to the area in which it is installed. If the boiler is installed in a location where a leak could cause damage, it is required to provide containment measures. Such measures include but are not limited to: a properly sized drain pan installed beneath the boiler and piped to an open drain line, or installing the boiler on a concrete floor pitched to a free flowing drain. Failure to provide containment measures is the sole responsibility of the owner and/or installer. Leakage damages ARE NOT covered by warranty. In addition, water leak detection devices and automatic water shutoff valves are readily available at plumbing supply houses. IT IS HIGHLY RECOMMENDED BY THE MANUFACTURER TO INSTALL WATER LEAK DETECTION DEVICES AND AUTOMATIC SHUTOFF VALVES IN ANY BOILER INSTALLATION WHERE A LEAKAGE OF WATER COULD RESULT IN PROPERTY DAMAGES.
NOTE: For closet installations, a combustible door or removable panel is acceptable front clearance. A 3" minimum clearance must be provided from the appliance front cover to the removable panel or combustible door.
Minimum Clearances from Combustible Materials
· Hot water pipes - at least 1" from combustible materials
· Exhaust vent pipe - at least 1" from combustible materials

Check with your local Authority Having Jurisdiction for requirements when installing the boiler in a garage or closet. Please read the entire manual before attempting installation. Failure to properly take factors such as venting, piping, condensate removal, and wiring into account before installation could result in wasted time, money, and possible property damage and personal injury.
Precautions If the boiler is located in a residential garage, per ANSI Z223.1:
· Install the boiler burner and ignition devices a minimum of 18" above the floor of the garage. This will ensure the burner and ignition devices are well off the floor.
· When raising the boiler ensure the entire bottom and fully filled weight of the boiler are fully supported.
· Locate or protect the boiler so it cannot be damaged by a moving vehicle.
The space must be provided with correctly sized combustion/ ventilation air openings for all other appliances located in the space with the boiler. For power venting installations using room air for combustion, refer to the venting section, this manual, for descriptions of confined and unconfined spaces. Do not install the boiler in an attic. Failure to comply with these warnings could result in substantial property damage, severe personal injury, or death.

Boiler Area Ventilation Air Openings - Closet Installations If the boiler is installed in a closet or alcove the boiler area/room must be ventilated. EXCEPTION: If the boiler area/room has a volume of 150 ft3 or greater, ventilation of the boiler area/room is not required. Each ventilation air opening must meet the minimum requirements of 1 in2 per 1000 BTU/hr., but not less than 100 in2. The lower ventilation opening must be located within 6 in. of the floor, while the upper opening must be located 6 in. from the top of the space.

F. Exhaust Vent and Intake Pipe The boiler is rated ANSI Z21.13 Category IV (pressurized vent, likely to form condensate in the vent) and requires a special vent system designed for pressurized venting. NOTE: The venting options described here (and further detailed in the Venting section, this manual) are the lone venting options approved for this boiler. Failure to vent the boiler in accordance with the provided venting instructions will void the warranty.

! WARNING
If the boiler area has a volume less than 150 ft3, it is considered a Closet or Alcove. In the US/Canada, PVC vent pipe and fittings SHALL NOT BE USED within the closet or alcove. Only approved CPVC, Polypropylene, or Stainless Steel vent pipe and fittings may be used. See Table 12 for a list of approved materials. Under all circumstances proper ventilation must be provided.
The space must be provided with correctly sized combustion/ ventilation air openings for all other appliances located in the space with the boiler. For power venting installations using room air for combustion, refer to the boiler venting section, this manual, for descriptions of confined and unconfined spaces. Do not install the boiler in an attic. The boiler cover must be securely fastened to prevent the boiler from drawing air from the boiler room. This is particularly important if the boiler is in a room with other appliances. Failure to comply with the above warnings could result in substantial property damage, severe personal injury, or death.
Alcove Installations Alcove installations have the same minimum dimensions as closet installations, except the installation must be completely open to the room at a distance no greater than 18 in. (457 mm) from the front of the boiler and the room must be at least three (3) times the size of the alcove. Provided these conditions are met, the boiler requires no extra ventilation air openings to the space. If these conditions are not met, follow the requirements for Closet Installations.

Failure to vent the boiler properly will result in serious personal injury or death.
Do not attempt to vent this boiler by any means other than those described in this manual. Doing so will void the warranty and may result in severe personal injury or death.
Vents must be properly supported. Boiler exhaust and intake connections are not designed to carry heavy weight. Vent support brackets must be within 1' of the boiler and the balance at 4' intervals. Boiler must be readily accessible for visual inspection for first 3' from the boiler. Failure to properly support vents could result in property damage, severe personal injury, or death.
The exhaust discharged by this boiler may be very hot. Avoid touching or other direct contact with the exhaust gases of the vent termination assembly. Doing so could result in severe personal injury or death. 1. Direct Vent of Exhaust and Intake If installing a direct vent option, combustion air must be drawn from the outdoors directly into the boiler intake and exhaust must terminate outdoors. There are three basic direct vent options detailed in this manual: 1. Side Wall Venting, 2. Roof Venting, and 3. Unbalanced Venting. Be sure to locate the boiler such that the exhaust vent and intake piping can be routed through the building and properly terminated. Different vent terminals can be used to simplify and eliminate

LP-550 Rev. 000 Rel. 022 Date 4.2.21

multiple penetrations in the building structure (see Optional Equipment in Venting Section). The exhaust vent and intake piping lengths, routing, and termination methods must all comply with the methods and limits given in the Venting Section, this manual. When installing a combustion air intake from outdoors, care must be taken to utilize uncontaminated combustion air. To prevent combustion air contamination, see Table 3.
2. Power Venting, Indoor Combustion Air in Confined or Unconfined Space
This boiler requires fresh, uncontaminated air for safe operation and must be installed in a mechanical room where there is adequate combustion and ventilating air. NOTE: To prevent combustion air contamination, see Table 3. Combustion air from the indoor space can be used if the space has adequate area or when air is provided through a duct or louver to supply sufficient combustion air based on the boiler input. Never obstruct the supply of combustion air to the boiler. If the boiler is installed in areas where indoor air is contaminated (see Table 3) it is imperative that the boiler be installed as direct vent so that all combustion air is taken directly from the outdoors into the boiler intake connection. Unconfined space is space with volume greater than 50 cubic feet per 1,000 BTU/hr (4.8 cubic meters per kW) of the total input rating of all fuel-burning appliances installed in that space. Rooms connected directly to this space through openings not furnished with doors are considered part of the space. See Venting Section for details. Confined space is space with volume less than 50 cubic feet per 1,000 BTU/hr (4.8 cubic meters per kW) of the total input rating of all fuel-burning appliances installed in that space. Rooms connected directly to this space through openings not furnished with doors are considered part of the space. When drawing combustion air from inside a conventionally constructed building to a confined space, such space should be provided with two permanent openings: one located 6" (15 cm) below the space ceiling, the other 6" (15cm) above the space floor. Each opening should have a free area of one square inch per 1,000 BTU/hr (22cm2/kW) of the total input of all appliances in the space, but not less than 100 square inches (645cm2). If the confined space is within a building of tight construction, air for combustion must be obtained from the outdoors as outlined in the Venting section of this manual.

In addition, the installing plumber or gas fitter shall observe that a hard wired carbon monoxide detector with an alarm and battery back-up is installed on each additional level of the dwelling, building, or structure served by the vented gas appliance. It shall be the responsibility of the property owner to secure the service of qualified licensed professionals for the installation of hard wired carbon monoxide detectors.
a. In the event that the vented gas fueled appliance is installed in a crawl space or attic, the hard wired carbon monoxide detector with alarm and battery back-up shall be installed on the next adjacent floor level. b. In the event that these requirements cannot be met at the time of completion of installation, the owner shall have a period of thirty (30) days to comply with the above requirements; provided, however, that during said thirty (30) day period, a battery operated carbon monoxide detector with an alarm shall be installed.
Do not attempt to vent this appliance by any means other than those described in this manual. Doing so will void the warranty and may result in severe personal injury or death.
Approved Carbon Monoxide Detectors: Each carbon monoxide detector as required in accordance with the above provisions shall comply with NFPA 70 and be ANSI/UL 2034 listed and IAS certified.
H. Prevent Combustion Air Contamination Install intake air piping for the boiler as described in the Venting Section, this manual. Do not terminate exhaust in locations that can allow contamination of intake air.
Ensure that the intake air will not contain any of the contaminants in Table 3. Contaminated air will damage the boiler, resulting in possible substantial property damage, severe personal injury, or death. For example, do not pipe intake air near a swimming pool or laundry facilities. These areas always contain contaminants.

When drawing combustion air from the outside into the mechanical room, care must be taken to provide adequate freeze protection.

Failure to provide an adequate supply of fresh combustion air can cause poisonous flue gases to enter the living space, resulting in severe personal injury or death. To prevent combustion air contamination, see Table 3.
G. Carbon Monoxide Detectors In the Commonwealth of Massachusetts and As Required by State and Local Codes: Installation of Carbon Monoxide Detectors: At the time of installation or replacement of the vented gas fueled appliance, the installing plumber or gas fitter shall observe that a hard wired carbon monoxide detector with an alarm and battery back-up is installed on the floor level where the gas appliance is installed, unless the appliance is located in a detached, uninhabitable structure separate from the dwelling, building, or structure used in whole or in part for residential purposes.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Products to Avoid

Areas Likely to Have Contaminants

Spray cans fluorocarbons

containing Dry cleaning / laundry areas and establishments

Permanent wave solutions

Swimming pools

Chlorinated waxes / cleaners Metal fabrication plants

Chlorine-based swimming pool chemicals

Beauty shops

Calcium chloride used for thawing

Refrigeration repair shops

Sodium chloride used for water softening

Photo processing plants

Refrigerant leaks

Auto body shops

Paint or varnish removers

Plastic manufacturing plants

Hydrochloric or Muriatic acid

Furniture refinishing areas and establishments

Cements and glues

New building construction

Antistatic fabric softeners used in clothes dryers

Remodeling areas

Chlorine-type

bleaches,

laundry detergents, and Garages and workshops

cleaning solvents

Adhesives used to fasten building products
Table 3 - Products and Areas Likely to Have Contaminants

NOTE: DAMAGE TO THE BOILER CAUSED BY EXPOSURE TO CORROSIVE VAPORS IS NOT COVERED BY WARRANTY. (Refer to the limited warranty for complete terms and conditions.)

as outlined, return doors, windows, exhaust fans, fireplace dampers, and any other gas burning appliances to their previous condition of use. 7. Any improper operation of the common venting system should be corrected to conform to the National Fuel Gas Code, ANSI Z223.1. When resizing any portion of the common venting system, the system should approach the minimum size as determined using the appropriate tables in Appendix G of ANSI Z223.1.
Figure 3 - CO Warning Label

I. Removing a Boiler from a Common Vent System

Do not install the boiler into a common vent with any other appliance. This will cause flue gas spillage or appliance malfunction, resulting in possible substantial property damage, severe personal injury, or death.

Failure to follow all instructions can result in flue gas spillage and carbon monoxide emissions, causing severe personal injury or death.
When removing an existing boiler, follow the steps below. 1. Seal any unused openings in the common venting system. 2. Visually inspect the venting system for proper size and horizontal pitch to determine if there is blockage, leakage, corrosion, or other deficiencies that could cause an unsafe condition. 3. If practical, close all building doors, windows, and doors between the space in which the boiler remains connected to the common venting system and other spaces in the building. Turn on clothes dryers and any appliances not connected to the common venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts, at maximum speed. Do not operate a summer exhaust fan. Close all fireplace dampers. 4. Place in operation the appliance being inspected. Follow the lighting instructions. Adjust the thermostat so the appliance will operate continuously. 5. Test for spillage at the draft hood relief opening after 5 minutes of main burner operation. Use the flame of a match or candle or smoke from a cigarette. 6. After it has been determined that each appliance remaining connected to the common venting system properly vents when tested
LP-550 Rev. 000 Rel. 022 Date 4.2.21

15
Figure 4 - Boiler Dimensions - NOTE: All Dimensions Are Approximate
LP-550 Rev. 000 Rel. 022 Date 4.2.21

EXHAUST VENT CONNECTION

COMBUSTION AIR INLET CONNECTION

ELECTRICAL CONNECTIONS

SYSTEM RETURN 4

A B C D
E

TOP VIEW

5 SYSTEM SUPPLY 6 RELIEF VALVE 7 CONDENSATE CONNECTION 8 GAS LINE CONNECTION 9 DISPLAY/CONTROL PANEL
O

F 5
3 J
6

LEFT SIDE VIEW

H FRONT VIEW

RIGHT SIDE VIEW

MODEL* 299 301 399

L M N O SHIPPING WEIGHT

24.75 17.50 14.50 7.38 3.25 36.50 14.50 4.75 21.00 11.00 7.88 4.63 9.50 3.50

211

24.75 17.50 14.50 7.38 3.25 36.50 14.50 4.75 21.00 11.00 7.88 4.63 9.50 3.50

211

31.75 24.75 21.50 10.75 3.75 36.00 14.50 4.75 21.00 11.00 7.88 4.63 9.50 3.50

256

MODEL *
299 301 399

MAX MBH
299 301 399

MIN MBH
29 30 39

AFUE
94.5 96.1 ** 96.5 **

HEATING CAPACITY
MBH 277
289
372

* "N" DENOTES NATURAL GAS "LP" DENOTES PROPANE

** THERMAL EFFICIENCY (NOT AFUE)
Figure 5 - Boiler Dimensions - NOTE: All Dimensions Are Approximate

SUPPLY/RETURN EXHAUST/AIR INLET GAS CONNECTION

1-1/4"

1-1/2"

LP-550-N 07/14/20

ALL DIMENSIONS ARE APPROXIMATE AND ARE SUBJECT TO CHANGE

LP-550 Rev. 000 Rel. 022 Date 4.2.21

J. Technical Specifications

Model

110

150

220

299

301

399

Installation

Indoor, Floor Standing or Wall Mount (with Optional Kit), Fully Condensing

Minimum / Maximum Input (Btu/Hr)

8,000 / 80,000

11,000 / 110,000

15,000 / 150,000

22,000 / 220,000

30,000 / 299,000

30,000 / 301,000

40,000 / 399,000

Heating Capacity (MBH)

100

138

204

277

289

385

Flue System

Category IV, Sealed Combustion Direct Vent, Power Vent

Minimum Combined Vent Run

16 feet

Maximum Combined Vent Run

3" (200 feet), 4" (275 feet)

4" (200 feet), 6" (275 feet)

Approved Exhaust Vent Materials

PVC, CPVC, PP, Stainless Steel

Shipping Weight (lbs)

108

113

126

164

211

256

Gas Supply

Pressure

3.5" to 14" WC

Manifold Pressure

Min / Max

NG/LP: -0.01" WC

Power Supply

120V 60 Hz, 6.3A

General Operating Conditions

Ambient Temperature Range: 33 104oF (0.6 40oC) Product Approvals and Requirements: ANSI Z21.13 / CSA 4.9

Ignition System

Direct Electronic Spark Ignition / Flame Rectification

Burner System

Premixed Fuel Modulation / Stainless Steel Metal Fiber Burner

Gas Valve System

Air Ratio Valve

Dimensions (in Inches)

27 18.5

14.5

24.5

19.5

26.5

36.5 24.75

36 31.75

Boiler Water Content (Gallons)

1.4

1.7

2.6

3.1

3.7

Minimum Flow Rate @ 30oF T (GPM)

5.3

7.3

14.6

Boiler Setpoint Temperature Range

50 190oF / 32 - 190oF (with Outdoor Reset Curve)

DHW Indirect Setpoint Temperature Range

70 185oF

Heat Exchanger

Water Pressure

MAWP

160

(PSI)

Pressure Relief Valve

Control Panel / Main Controller

LCD Display with LED Indicators / 928 SIT Control

Connection Sizes

Supply / Return Gas Inlet

1" NPTF 3/4" NPTF

1 1/4" NPTF 1" NPTF

1" NPTF

Materials

Cabinet Heat Exchanger

Powder Coated Galvaneal Steel 316L Stainless Steel Water Tube

Safety Devices Table 4 - Technical Specifications

Flame Rectifier Probe, Dual Water Supply Temperature Sensor (210oF), Water Pressure High Limit
Switch, Freeze Protection, Condensate Pressure Switch, Condensate Trap with Float, Dual Flue Sensor (210oF), Blocked Vent Pressure Switch, Optional External Low Water Cut-Off

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 4 - Piping
! WARNING
Failure to follow the instructions in this section WILL VOID the warranty and may result in property damage, severe personal injury, or death.
The National Standard Plumbing Code, the National Plumbing Code of Canada, and the Uniform Plumbing Code limit heat transfer fluid pressure to less than the minimum working pressure of the potable water system up to 30 PSI maximum. In addition, the heat transfer fluid must be water or another non-toxic fluid having a toxicity of Class 1, as listed in Clinical Toxicology of Commercial Products, 5th Edition. Failure to follow this warning could result in property damage, severe personal injury, or death.
CAUTION
Galvanized steel fittings must not be used in a system with this boiler. Doing so WILL VOID the warranty. Use only copper, brass, or stainless steel fittings.
Plumbing of this product should only be done by a qualified, licensed plumber in accordance with all local plumbing codes. The boiler may be connected to an indirect water heater to supply domestic hot water. HTP offers indirect water heaters in either stainless steel or glass-lined construction.
A. General Plumbing Information
The building piping system must meet or exceed the the piping requirements in this manual.
Use two wrenches when tightening water piping at boiler. Use one wrench to prevent the boiler return or supply line from turning. Failure to prevent piping connections from turning could cause damage to boiler components.
The control module uses temperature sensors to provide both high limit protection and modulating temperature control. The control module may also provide low water protection (through the addition of an optional kit) by sensing the water level in the heat exchanger. An optional flow switch may be installed on the supply of the system to activate the boiler when there is enough flow. Some codes/jurisdictions may require additional external controls.
The water connections must be installed in accordance with all local and national plumbing codes, or any applicable standard which prevails. · Pipe material must be suitable to meet local codes and industry
standards. · The pipe must be cleaned and without blemish before any
connections are made. · Isolation (shut-off valves) should be used to ease future servicing. · All piping should be insulated. It is recommended to install a shut-off valve and a union in the return and supply piping to ease future servicing. If there is a backflow preventer or any type of a no return valve in the system, install an additional tee here suitable for an expansion tank. NOTE: The addition of a high temperature limiting device is important if the boiler is to be connected to a domestic hot water system.

B. Relief Valve Connect discharge piping to a safe disposal location following the guidelines below.
To avoid water damage or scalding due to relief valve operation: · Discharge line must be connected to relief valve outlet and run to a safe place of disposal. Terminate the discharge line in a manner that will prevent possibility of severe burns or property damage should the relief valve discharge. · Discharge line must be as short as possible and the same size as the valve discharge connection throughout its entire length. · Discharge line must pitch downward from the valve and terminate at least 6" above the floor drain, making discharge clearly visible. · The discharge line shall terminate plain, not threaded, with a material serviceable for temperatures of 375oF or greater. · Do not pipe discharge to any location where freezing could occur. · No valve may be installed between the relief valve and boiler or in the discharge line. Do not plug or place any obstruction in the discharge line. · Test the operation of the relief valve after filling and pressurizing the system by lifting the lever. Make sure the valve discharges freely. If the valve fails to operate correctly, immediately replace with a new properly rated relief valve. · Test T&P valve at least once annually to ensure the waterway is clear. If valve does not operate, turn the boiler "off" and call a plumber immediately. · Take care whenever operating relief valve to avoid scalding injury or property damage.
FAILURE TO COMPLY WITH THE ABOVE GUIDELINES COULD RESULT IN FAILURE OF RELIEF VALVE OPERATION, RESULTING IN POSSIBILITY OF SUBSTANTIAL PROPERTY DAMAGE, SEVERE PERSONAL INJURY, OR DEATH.
RE-INSPECTION OF T&P RELIEF VALVES: T&P valves should be inspected AT LEAST ONCE EVERY THREE YEARS, and replaced if necessary, by a licensed plumbing contractor or qualified service technician to ensure that the product has not been affected by corrosive water conditions and to ensure that the valve and discharge line have not been altered or tampered with illegally. Certain naturally occuring conditions may corrode the valve and its components over time, rendering the valve inoperative. Such conditions can only be detected if the valve and its components are physically removed and inspected. Do not attempt to conduct an inspection on your own. Contact your plumbing contractor for a re-inspection to assure continued safety.
FAILURE TO RE-INSPECT THE T&P VALVE AS DIRECTED COULD RESULT IN UNSAFE TEMPERATURE AND/OR PRESSURE BUILDUP WHICH CAN RESULT IN PROPERTY DAMAGE, SERIOUS PERSONAL INJURY, OR DEATH.
Do not thread a cap or plug into the relief valve or relief valve line under any circumstances! Explosion and property damage, serious injury, or death may result.
C. Backflow Preventer Use a backflow preventer specifically designed for hydronic boiler installations. This valve should be installed on the cold water fill supply line per local codes.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

All piping methods shown in this manual use primary/secondary connection to the boiler loop. This is to avoid the possibility of inadequate flow through the boiler. For other piping methods, consult your HTP representative.

Sizing Space Heat System Piping 1. See Applications in this manual. In all diagrams, the space heating system is isolated from the boiler loop by the primary/secondary connection. 2. Size the piping and components in the space heating system using recognized design methods.

D. Expansion Tank Expansion Tank and Make-Up Water 1. Ensure that the expansion tank is sized to correctly handle boiler and system water volume and temperature.

Expansion tanks must be sized according to total system volume. This includes all length of pipe, all fixtures, boilers, etc. Failure to properly size for system expansion could result in wasted time, money, possible property damage, serious injury, or death.

Undersized expansion tanks cause system water to be lost from the relief valve, causing make-up water to be added. Eventual boiler failure can result due to excessive make-up water addition. SUCH FAILURE IS NOT COVERED BY WARRANTY.
DO NOT install automatic air vents on closed type expansion tank systems. Air must remain in the system and return to the tank to provide an air cushion. An automatic air vent would cause air to leave the system, resulting in improper operation of the expansion tank.

Expansion Tank Sizing

Model

Heat Exchanger Volume (Gallons)

1.4

110

1.7

150

220

2.6

299 / 301

3.1

399

3.7

Table 5 - Expansion Tank Sizing

2. The expansion tank must be located as shown in Applications, this

manual, or following recognized design methods. See expansion tank

manufacturer's instructions for details.

3. Connect the expansion tank to the air separator only if the air

separator is on the suction side of the circulator. Always install the

system fill connection at the same point as the expansion tank

connection to the system.

4. Most chilled water systems are piped using a closed type expansion

tank.

DIAPHRAGM (OR BLADDER) EXPANSION TANK

Always install an automatic air vent on top of the air separator to

remove residual air from the system.

E. Circulators

F. Hydronic Piping with Circulators, Zone Valves, and Multiple Boilers
This boiler is designed to function in a closed loop hydronic system. We have included a temperature and pressure gauge that allows the user to monitor the system pressure and outlet temperature from the boiler. It is important to note that the boiler has a minimal amount of pressure drop that must be calculated when sizing the circulators. Unless the system has a closed type expansion tank, each boiler installation must have an air elimination device that will remove air from the system. Install the boiler so the gas ignition system components are protected from water (dripping, spraying, etc.) Allow clearance for basic service of boiler circulator, valves and other components. Observe the minimum 1" clearance around all uninsulated hot water pipes when openings around pipes are not protected by noncombustible materials. On a boiler installed above radiation level, some states and local codes require a low water cut off device, which is an optional part available through HTP (Part # 7450P-904). Check with local codes for additional requirements. If the boiler supplies hot water to heating coils in air handler units, flow control valves or other devices must be installed to prevent gravity circulation of boiler water in the coils during the cooling cycle. Chilled water medium must be piped in parallel with the boiler. Freeze protection for new or existing systems must use glycol that is specifically formulated for this purpose. Antifreeze must include inhibitors that will prevent the glycol from attacking the metallic system components. Make certain that the system fluid is checked for the correct glycol concentration and inhibitor level. The system should be tested at least once a year and as recommended by the producer of the glycol solution. Allowance should be made for the expansion of the glycol solution in the system piping. Example: 50% by volume glycol solution expands 4.8% in volume for a temperature increase from 32oF to 180oF, while water expands 3% with the same temperature rise.
CAUTION
The boiler should not be operated as a potable hot water heater. The boiler should not be used as a direct hot water heating device.
Use at least the MINIMUM pipe size for all appliance loop piping. This is to avoid the possibility of inadequate flow through the appliance. Using less than the required minimum pipe size and piping could result in system problems, property damage, and premature appliance failure. Such problems ARE NOT covered by product warranty.

DO NOT use the boiler circulator in any location other than the ones shown in this manual. The boiler circulator location is selected to ensure adequate flow through the boiler. Failure to comply with this caution could result in unreliable performance and nuisance shutdowns from insufficient flow.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

G. Circulator Sizing In addition, the heat exchanger has a minimum total water volume that must be taken into account when sizing the circulator. Minimum flow rates are listed in the table below.

Model 80 110

Minimum Boiler Flow Rates Minimum Flow (GPM) 5.3 7.3

150

220

14.6

299 / 301

399

Table 6 - Minimum Flow Rates

The heat exchanger has a pressure drop that must be considered in your system design. Refer to Table 7 for pressure drop through the heat

exchanger.

Heat Exchanger Pressure Drop

Flow Rate in GPM and Corresponding Pressure Drop in Feet ( P')

Model 6

9 10 11 12 13 14 15 16 17 18 19 20 21 22

80 10' 14' 17' 21' 26' *

* **

110 *

* 15' 17' 22' 25' 33' *

* **

150 *

* 12' 15' 17' 19' 22' 27' *

* **

220 *

8' 10' 11.5' 13' 15' 16.5' 17' 19'

299 301

* 13' 14' 15'

399 *

* **

Model 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39

* **

110 *

* **

150 *

* **

220 21' 23' 24' *

* **

299 301

16.5'

18'

20'

22'

24'

26'

29'

33'

36'

* **

399 *

* 12.9' 13.6' 14' 15.7' 17' 18' 19.4' 21' 22.5' 26' 28' 31' 34' 39'

Table 7 - *Do not operate the boiler at these flow rates. These low or high flow rates will damage the heat exchanger or related components. Damages due to improper operation ARE NOT covered by warranty.

The chart below represents various system design temperature rise through the boiler along with respective flows and friction loss. This is provided to aid in circulator selection.

System Temperature Rise Chart

20°t

Model

Friction Ft

Flow Rate (GPM)

17'

110

25'

150

27'

220

19'

299 301

29'

399

39'

Table 8 - Temperature Rise, Friction Ft and Flow Rate

25°t

Friction Ft

Flow Rate (GPM)

10'

6.6

9.1 17'
12.5

13'

18.3

18'

24.5

19'

32.5

Friction Ft 7'
12'

30°t Flow Rate (GPM) 5.3 7.3 10 14.6

20 13'
26

LP-550 Rev. 000 Rel. 022 Date 4.2.21

The chart below represents the combined flow rates and pipe sizes when using multiple boilers to design the manifold system for the primary circuit. To size, simply add up the number of boilers and the required flow rates for the system design temperature. Example: (5) 220 Model boilers with a design of 20°t degree temperature rise with each boiler having an individual flow rate of 22 GPM. To correctly size the manifold feeding these (5) boilers you would need a pipe size of 4".

Multiple Boiler Manifold Piping

Flow Rate (GPM) 16 22 24 30 32 33 40 44 45 48 50 55 60 66 75 80 85 88 90 100 110

Pipe Dia. (In.)

Table 9 - Multiple Boiler Manifold Piping

2 1/2

Figure 6 - Multiple Boiler Manifold Piping

Multiple Boiler Manifold Piping

Flow Rate (GPM) 120 132 150 160 170 179 200 210 239 240 250 255 300 340 350 400 425 510 595 680

Pipe Dia. (In.)

Table 10 - Multiple Boiler Manifold Piping

H. Check / Control Water Chemistry
Chemical imbalance of the water supply may affect efficiency and cause severe damage to the appliance and associated equipment. It is important that the water chemistry on both the domestic hot water and central heating sides are checked before installing the appliance. Water quality must be professionally analyzed to determine whether it is necessary to treat the water. Various solutions are available to adjust water quality. Adverse water quality will affect the reliability of the system. In addition, operating temperatures above 135oF will accelerate the build-up of lime scale and possibly shorten appliance service life. Failure of an appliance due to lime scale build-up, low pH, or other chemical imbalance IS NOT covered by the warranty.
Closed loop water must be free of corrosive chemicals, sand, dirt, and other contaminates. It is up to the installer to ensure the water does not contain corrosive chemicals or elements that can damage the heat exchanger.
If you suspect that your water is contaminated in any way, discontinue use of the appliance and contact an authorized technician or licensed professional.
· Water pH between 6.5 and 8.5 · Hardness less than 7 grains (120 mg/L) (Water temperatures
of 140oF and greater) · Chloride concentration less than 100 ppm (mg/L) · Total Dissolved Solids (TDS) less than 500 ppm (mg/L)

*NOTE: It is recommended to clean the heat exchanger at least once a year to prevent lime scale buildup. To clean the heat exchanger, follow the maintenance procedure in this manual.
Clean system to remove sediment* 1. You must thoroughly flush the system (without boiler connected) to remove sediment. The high-efficiency heat exchanger can be damaged by buildup or corrosion due to sediment. 2. For zoned systems, flush each zone separately through a purge valve. (If purge valves and isolation valves are not already installed, install them to properly clean the system.) 3. Flush system until water runs clean and you are sure piping is free of sediment. *NOTE: It is recommended you clean heat exchanger at least once a year to prevent lime scale buildup. Follow the maintenance procedure to clean the heat exchanger in the Maintenance Section of this manual. Test/replace freeze protection fluid 1. For systems using freeze protection fluids, follow fluid manufacturer's instructions to verify inhibitor level and that other fluid characteristics are satisfactory. 2. Freeze protection fluid must be replaced periodically due to degradation of inhibitors over time. Follow all fluid manufacturer instructions.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Piping Components Heating System Piping System piping MUST be sized per technical pipe requirements listed in Tables 7, 8, and 9. Reducing pipe size can restrict flow rate through the boiler, causing inadvertent short cycling and poor system performance. Check Valves Field supplied. Check valves are recommended for installation as shown in Applications. Isolation Valves Field supplied. Full port ball valves are required. Failure to use full port ball valves could result in a restricted flow rate through the boiler. Anti-Scald Mixing Valve Field supplied. An anti-scald mixing valve is recommended when storing domestic hot water above 115°F. Unions Field supplied. Recommended for unit serviceability. DO NOT USE GALVANIZED UNIONS! ONLY BRASS, COPPER, OR STAINLESS STEEL. Pressure Relief Valve Factory supplied on boiler. The pressure relief valve is sized to ASME specifications. Storage tank may require additional relief valves depending on local codes.

Minimum Pipe Sizes

80 / 110 / 150 / 220

1" NPT

299 / 301

1 1/4" NPT

399

1 1/2" NPT

J. Fill and Purge Heating System 1. Attach the hose to balance and purge hose connector or drain valve and run hose to nearest drain. 2. Close the other side of the balance and purge valve or shut off valve after the drain. 3. Open the first zone balance and purge or drain valve to let water flow out of the hose. If zone valves are used, open the valves one at a time manually. NOTE: You should check zone valve manufacturer's instructions prior to opening valves manually, so as not to damage the zone valve. 4. Manually operate fill valve regulator. When water runs out of the hose, you will see a steady stream without bubbles. Close the balance and purge valve or drain to stop the water from flowing. Disconnect the hose and connect it to next zone to be purged. 5. Repeat this procedure for additional zones (one at a time).
For installations that incorporate standing iron radiation and systems with manual vents at the high points, follow the previous section and, starting with the nearest manual air vent, open the vent until water flows out. Then close the vent. Repeat the procedure, working your way toward the furthest air vent. It may be necessary to install a basket strainer in an older system where larger amounts of sediment may be present. Annual cleaning of the strainer may be necessary.
Upon completion, make sure that the fill valve and zone valves are in automatic positions. You must also assure the purge and shut off valves are in open positions.

Table 11 - Minimum Pipe Sizes

K. Freeze Protection Fluids

I. Plumbing

This boiler should not be operated as a potable hot water heater. It should not be used as a direct hot water heating device.
NOTE: Observe the minimum 1" clearance around all uninsulated hot water pipes when openings around pipes are not protected by non-combustible materials. Basic steps are listed below, with illustration that will guide you through the installation of the boiler. 1. Connect the system return marked "Boiler Return". 2. Connect the system supply marked "Boiler Supply". 3. Install a purge and balance valve or shut off valve and drain on the system return to purge air out of each zone. 4. Install a back flow preventer on the cold feed make-up water line. 5. Install a pressure reducing valve on the cold feed make-up water line (15 psi nominal on the system return). This boiler has a maximum working pressure of 160 psi. You may order a higher pressure relief valve kit from the factory. Check temperature and pressure gauge when operating. It should read a minimum pressure of 12 psi. 6. Install a circulator as shown in Applications (this manual). Make sure the circulator is properly sized for the system and friction loss. 7. Install an expansion tank on the system supply. Consult the expansion tank manufacturer's instruction manual (see Part 4, Section D for water volume) for specific information relating to expansion tank installation. Size the expansion tank for the required system volume and capacity. 8. Install an air elimination device on the system supply. 9. Install a drain valve at the lowest point of the system. Note: The boiler cannot be drained completely of water without purging the unit with an air pressure of 15 PSI. 10. The relief valve and temperature and pressure gauge are included in the accessory kit. A discharge line should be installed 6"above the drain in the event of a pressure relief. The pipe size must be the same size as the relief valve outlet. NEVER BLOCK THE OUTLET OF THE SAFETY RELIEF VALVE.

Use only inhibited propylene glycol solutions which are specially formulated for hydronic systems. Ethylene glycol is toxic and can attack gaskets and seals used in hydronic systems. Glycol mixtures should not exceed 50%. Failure to do so could result in property damage, severe personal injury, or death due to scalds.
· Glycol in hydronic applications should include inhibitors that prevent the glycol from attacking metallic system components. Make certain that the system fluid is checked for the correct glycol concentration and inhibitor level.
· The glycol solution should be tested at least once a year or as recommended by the glycol manufacturer.
· Anti-freeze solutions expand more than water. For example: A 50% by volume solution expands 4.8% in volume for a temperature increase from 32oF to 180oF, while water expands 3% over the same temperature rise. Allowances must be made in system design for expansion.
· A 30% mixture of glycol will result in a BTU output loss of 15% with a 5% increase in head against the system circulator.
· A 50% mixture of glycol will result in a BTU output loss of 30% with a 50% increase in head against the system circulator.
It is highly recommended that you carefully follow the glycol manufacturer's recommended concentrations, expansion requirements, and maintenance recommendations (pH additive breakdown, inhibitor reduction, etc.) You must carefully calculate the additional friction loss in the system as well as the reduction in heat transfer coefficients.
L. Zoning with Zone Valves 1. When zoning with zone valves, connect the boiler to the system as shown in Applications. The primary/secondary piping shown ensures the boiler loop will have sufficient flow. It also avoids applying the high head of the boiler circulator to the zone valves.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

23 2. Connect DHW (domestic hot water) piping to indirect storage water heater as shown in Applications. M. Zoning with Circulators 1. When using circulator zoning, connect the boiler to the system as shown in Applications. NOTE: The boiler circulator cannot be used for a zone. It must only supply the boiler loop. 2. Install a separate circulator for each zone. 3. Connect DHW (domestic hot water) piping to indirect storage water heater as shown in Applications. N. Multiple Boilers 1. Connect multiple boilers as shown in Applications. 2. All piping shown is reverse return to assure balanced flow throughout the connected boilers. 3. Each connected boiler must have its own circulator pump to assure adequate flow. 4. Connect DHW (domestic hot water) piping to indirect storage water heater as shown in Applications. 5. The system flow (secondary loop) must be greater than the boiler's primary loop flow. Water temperature above 140oF requires the circulator pump to run continuously and water hardness between 5 and 7 grains. Hardness above 7 grains will damage the heat exchanger and shorten the service life of the boiler.
LP-550 Rev. 000 Rel. 022 Date 4.2.21

24 O. Applications* *NOTE: Systems shown are primary/secondary piping systems. These recommended systems have a primary (boiler) loop, and secondary circuits for heating. The primary loop and secondary circuits have separate circulators. The use of other near boiler piping configurations could result in improper flow rates, leading to inadvertent boiler high limit shutdowns and poor system performance. NOTE: In piping applications utilizing a single zone, it is recommended that the installer use flow / check valves with weighted seats at or near the appliance to prevent gravity circulation.
Figure 7 - Boiler with Indirect Priority NOTES: 1. This drawing is meant to show system piping concept only. 2. A mixing valve is recommended if the DHW temperature is set above 119oF. 3. Install a minimum of 12 diameters of straight pipe upstream of all circulators. 4. Piping shown is Primary/Secondary. 5. System flow (secondary loop) should be greater than the boiler primary loop flow. In all cases, the boiler primary loop flow rate must be maintained above the minimum flow rates published in this manual. 6. Installations must comply with all local codes. 7. In Massachusetts, a vacuum relief valve must be installed in the cold water line per 248 CMR. The piping will not support the weight of the circulators. Refer to the circulator manufacturer's instructions to properly support the circulator. Failure to comply with these instructions could result in property damage, severe personal injury, or death.
LP-550 Rev. 000 Rel. 022 Date 4.2.21

25
Figure 8 - Cascaded Boilers with Indirect Priority on a Single Boiler NOTES: 1. This drawing is meant to show system piping concept only. 2. A mixing valve is recommended if the DHW temperature is set above 119oF. 3. Install a minimum of 12 diameters of straight pipe upstream of all circulators. 4. Piping shown is Primary/Secondary. 5. System flow (secondary loop) should be greater than the boiler primary loop flow. In all cases, the boiler primary loop flow rate must be maintained above the minimum flow rates published in this manual. 6. Installations must comply with all local codes. 7. In Massachusetts, a vacuum relief valve must be installed in the cold water line per 248 CMR. 8. Reference Figure 6 to determine manifold pipe sizing. The piping will not support the weight of the circulators. Refer to the circulator manufacturer's instructions to properly support the circulator. Failure to comply with these instructions could result in property damage, severe personal injury, or death.
LP-550 Rev. 000 Rel. 022 Date 4.2.21

26
Figure 9 - Space Heating NOTES: 1. This drawing is meant to show system piping concept only. 2. Install a minimum of 12 diameters of straight pipe upstream of all circulators. 3. Piping shown is Primary/Secondary. 4. System flow (secondary loop) should be greater than the boiler primary loop flow. In all cases, the boiler primary loop flow rate must be maintained above the minimum flow rates published in this manual. 5. Installations must comply with all local codes. 6. In Massachusetts, a vacuum relief valve must be installed in the cold water line per 248 CMR. The piping will not support the weight of the circulators. Refer to the circulator manufacturer's instructions to properly support the circulator. Failure to comply with these instructions could result in property damage, severe personal injury, or death.
LP-550 Rev. 000 Rel. 022 Date 4.2.21

27
Figure 10 - Cascaded Space Heating NOTES: 1. This drawing is meant to show system piping concept only. 2. Install a minimum of 12 diameters of straight pipe upstream of all circulators. 3. Piping shown is Primary/Secondary. 4. System flow (secondary loop) should be greater than the boiler primary loop flow. In all cases, the boiler primary loop flow rate must be maintained above the minimum flow rates published in this manual. 5. Installations must comply with all local codes. 6. In Massachusetts, a vacuum relief valve must be installed in the cold water line per 248 CMR. The piping will not support the weight of the circulators. Refer to the circulator manufacturer's instructions to properly support the circulator. Failure to comply with these instructions could result in property damage, severe personal injury, or death.
LP-550 Rev. 000 Rel. 022 Date 4.2.21

28 Part 5 - Venting

The boiler must be vented as detailed in this section. Ensure exhaust vent and intake piping complies with these instructions regarding vent system. Inspect finished exhaust vent and intake piping thoroughly to ensure all joints are well secured, airtight, and comply with all applicable code requirements, as well as the instructions provided in this manual. Failure to properly install the vent system will result in severe personal injury or death.
A. General

This boiler is certified as a "Category IV" appliance and requires a special venting system. The vent system will operate with a positive pressure in the pipe. Exhaust gases must be piped directly outdoors using the vent materials and rules outlined in these instructions. Do not connect vent connectors serving appliances vented by natural draft into any portion of mechanical draft systems operating under positive pressure. Follow the venting instructions carefully. Failure to do so will result in substantial property damage, severe personal injury, or death.
1. Installation should be made in accordance with the regulations of the Authority Having Jurisdiction, local code authorities, and utility companies which pertain to this type of water heating equipment. 2. Install the venting system in accordance with these instructions and with the National Fuel Gas Code, ANSI Z223.1/NFPA 54, CAN/ CGA B149, and / or applicable provisions of local building codes. 3. This boiler must be vented with materials, components, and systems listed and approved for Category IV appliances.
Exhaust and intake are to be piped separately. This boiler cannot share a common exhaust or intake with multiple appliances. Failure to follow these instructions will result in substantial property damage, severe personal injury, or death.
NOTE: To avoid contamination often contained in indoor air, it is best to pipe all intake combustion air directly to the outdoors. NOTE: Care must be taken to prevent condensate freezing in the exhaust vent pipe system. See local, state, provincial, and national codes for best practices to prevent condensate freezing in the exhaust vent pipe system.
Improper seating of vent pipe gaskets can cause eventual gasket failure and exhaust gas leakage. Ensure the exhaust vent pipe is properly beveled and seated before insertion into the flue adapter. Failure to do so could result in property damage, severe personal injury, or death.
It is required to insert the provided exhaust and intake screens into the vent terminations to prevent blockage caused by debris or birds. Failure to keep terminations clear could result in property damage, severe personal injury, or death.
Exhaust vent adaptors are not designed as load-bearing devices, and must not be used to support exhaust vent piping. All vent pipes must be properly connected, supported, and the exhaust vent must be pitched a minimum of 1/4" per foot back to the boiler to allow drainage of condensate. Failure to properly support vent piping and follow the information in this statement could result in product damage, severe personal injury, or death.

Due to the extreme flammability of most glues, cements, solvents, and primers used to join plastic exhaust vent and intake pipes, explosive solvent vapors must be cleared from all vent piping before start-up. Avoid using excess cement or primer, as this may pool in the vent pipes. Vent assemblies should be allowed to cure for a period of at least 8 hours before powering a connected appliance. Failure to follow these instructions will result in substantial property damage, severe personal injury, or death. It is the installers' responsibility to understand the hazards associated with explosive solvents and take the necessary precautions to avoid these risks.

· Only Stainless Steel exhaust vent pipe material may be insulated.

· DO NOT insulate the first three (3)

linear feet of the exhaust vent run.

Within First Three (3) Linear Feet of Appliance Exhaust Vent Adapter

· DO NOT insulate PVC, CPVC, or

Polypropylene exhaust vent pipe

material. Doing so will cause

Enclosed

increased vent wall temperatures,

Space

which could result in vent pipe failure.

· CPVC, Polypropylene, or Stainless Steel pipe material MUST be used if the first three (3) linear feet of the Exhaust exhaust vent run passes through an enclosed space greater than 6" in

Length Greater than Six (6) Inches
LP-179-JJ 11/30/17

length, such as a wall or ceiling.*

· If CPVC is used to meet these requirements, the balance may be

installed with approved PVC pipe.

· If Polypropylene or Stainless Steel is used to meet these

requirements, the balance of the vent run MUST be installed with

the same material.

· Failure to comply with these requirements could result in property

damage, severe personal injury, or death.

*This rule applies when the exhaust vent passes through the enclosed space

into another interior space, i.e. through a floor or wall from the mechanical

room into another room. This rule DOES NOT apply when the exhaust vent

passes through the enclosed space immediately to the exterior of the

building.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

B. Approved Materials for Exhaust Vent and Intake Pipe

Item

Material

Pipe and Fittings Approved for Intake ONLY

ABS*

Standards for Installation In:

United States

Canada

ANSI/ASTM D2661

Pipe Approved for Intake OR Exhaust Vent

PVC Schedule 40/80 PVC-DWV Schedule 40/80
CPVC Schedule 40/80 Polypropylene
Stainless Steel AL29-4C

UL-1738 or ANSI/ASTM D1785

UL-1738 or ANSI/ASTM D2665 UL-1738 or ANSI/ASTM F441

UL-1738 or ULC-S636

Certified for Category IV and Direct Vent Appliance Venting

Pipe Fittings

PVC Schedule 40 PVC Schedule 80 CPVC Schedule 40 CPVC Schedule 80

UL-1738, ANSI/ASTM D2466 or D2665 UL-1738, ANSI/ASTM D2467 or D2665
UL-1738 or ANSI/ASTM F438 UL-1738 or ANSI/ASTM F439

UL-1738 or ULC-S636

Pipe Cement Pipe Primer

ABS* PVC CPVC PVC / CPVC

ANSI/ASTM D2235 ANSI/ASTM D2564 ANSI/ASTM F493
ASTM F656

ANSI/ASTM D2235
ULC-S636 Cements and Primers

· The exhaust and intake components installed with this appliance must be used for near appliance piping BEFORE transitioning to the approved materials listed above. DO NOT REMOVE these installed components. Doing so WILL VOID appliance warranty.
· In the US/Canada, PVC vent pipe and fittings SHALL NOT BE USED within the closet or alcove. Only approved CPVC, Polypropylene, or Stainless Steel vent pipe and fittings may be used.
· PVC / CPVC pipe and fittings of the same diameter are considered interchangeable.

· The use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenolsulfone) in exhaust venting systems is prohibited.
· Covering non-metallic vent pipe and fittings with thermal insulation is prohibited. · When installing AL29-4C vent piping, DO NOT mix AL29-4C piping from different manufacturers unless using adapters specifically
designed for the purpose by the manufacturer. · DO NOT mix components from different venting systems without proper adapters. The vent system could fail, causing leakage of flue
products into the living space. Use only the approved pipe and fitting materials, and primer and cement specifically designed for the material used, as listed in the above table. · A double wall vent or insulated material may be used when using stainless steel vent material in a freezing climate. · *ABS may be used for air intake applications ONLY. · Contact the venting material manufacturer if there is any question about the applicability of the proposed venting material. Failure to follow these directions will result in substantial property damage, severe personal injury, or death.

Table 12 - Approved Materials for Exhaust Vent and Intake Pipe
! WARNING
DO NOT mix components from different venting systems without proper adapters. The vent system could fail, causing leakage of flue products into the living space. Use only the approved pipe and fitting materials, and primer and cement specifically designed for the material used, as listed in the above table. Failure to do so could result in property damage, serious injury, or death.
CAUTION
High heat sources (generating heat 100oF / 37oC or greater, such as boiler flue pipes, space heaters, etc.) may damage plastic components of the boiler as well as plastic vent pipe materials. Such damages ARE NOT covered by warranty. It is recommended to keep a minimum clearance of 8" from high heat sources. Observe heat source manufacturer instructions, as well as local, state, provincial, and national codes, laws, regulations, and ordinances when installing this boiler and related components near high heat sources.

! DANGER
You must not use "B" vent in an exhaust application. "B" vent is for intake applications ONLY. Using "B" vent in an exhaust application will result in serious injury or death.
C. Additional Requirements for Installation in Canada 1. Installations must be made with a vent pipe system certified to ULC-S636. 2. The first three (3) feet of vent pipe from the boiler flue outlet must be readily accessible for visual inspection. 3. The components of the certified vent system must not be interchanged with other vent systems or unlisted pipe / fittings.
! WARNING
It is required to insert exhaust and intake screens into the vent terminations to prevent blockage caused by debris or birds. Failure to keep terminations clear could result in property damage, severe personal injury, or death.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

D. Exhaust Vent and Intake Pipe Location
INSIDE CORNER DETAIL

G
E

B B

OPERABLE

FIXED

CLOSED

IE
K

M B

C
FIXED CLOSED
OPERABLE

E
E
F
E

EB
L

D I
E
K
LP-179-CC 03/28/17

E Exhaust Vent Terminal I Intake Pipe Terminal

Area Where Intake Terminal Is Not Permitted

Figure 11 - Exit Terminals for Direct Vent Systems - ANSI Z223.1 / NFPA 54 for US and CAN/CSA B149.1 for Canada

DESCRIPTION

CANADA

A Clearance above grade, veranda, porch, deck, or balcony

1 foot (30 cm)

B Clearance to window or door that may be opened

Direct Vent

1 foot

Power Vent

4 ft below or to side of opening; 1 ft above opening

3 feet (91 cm)

C Clearance to permanently closed window

Vertical clearance to ventilated soffit located above the terminal within a horizontal distance 2 feet (61 cm) from the center line of the terminal

E Clearance to unventilated soffit

F Clearance to outside corner

G Clearance to inside corner

Clearance to each side of center line extended above meter / regulator assembly

I Clearance to service regulator vent outlet

Above a regulator

within 3 feet (91 cm)

horizontally of the

vertical center line of

the regulator vent outlet

to a maximum vertical

distance of 15 ft (4.5 m)

Direct Vent

1 foot

Clearance to nonmechanical air supply inlet to building or

the combustion air inlet to any other appliance

Power Vent

4 ft below or to side of opening; 1 ft above opening

3 feet (91 cm)

K Clearance to mechanical air supply inlet

3 feet above if within 10 feet horizontally

Clearance above paved sidewalk or paved driveway located Direct Vent

on public property

Power Vent

* 7 feet (2.13 m)

6 feet (1.83 m) 7 feet (2.13 m)

M Clearance under veranda, porch deck, or balcony

1 foot (30 cm)

Table 13 - Vent Termination Clearances - *NOTE: For clearances not specified in ANSI Z223.1 / NFPA 54 for US and CAN/CSA B149.1 for Canada, please use clearances in accordance with local installation codes and the requirements of the gas supplier.

The building owner is responsible for keeping the exhaust and intake terminations free of snow, ice, or other potential blockages, as well as scheduling routing maintenance. Failure to keep the vent piping terminations clear and properly maintain the heater could result in property damage, severe personal injury, or death.

For each floor containing bedroom(s), a carbon monoxide detector and alarm shall be placed in the living area outside the bedrooms, as well as in the room that houses the heater. Detectors and alarms shall comply with NFPA 720 (latest edition). Failure to comply with these requirements could result in product damage, severe personal injury, or death.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

E. Exhaust Vent and Intake Pipe Sizing 1. The exhaust vent and intake pipe size is 3" for 80 - 220 models and 4" for 299 - 399 models. 2. The maximum total equivalent length of exhaust vent and intake pipe should not exceed 200 feet.
a. The equivalent length of elbows, tees, and other fittings are listed in the Friction Loss Table.

Friction Loss Equivalent in Piping and Fittings

Fittings or Piping

Equivalent Feet

90 Degree Elbow*

45 Degree Elbow

Coupling

Air Inlet Tee

Straight Pipe

Concentric Kit

N/A

Standard Vent Connection and
Maximum Total Equivalent Length

Reducing Coupling

3" (200')

4" x 3"

4" (200')

6" x 4"

6" (200')

8" x 6"

Table 15 - Vent Run Transition

Increased Vent Size and Maximum Total Equivalent Length
4" (275') 6" (275') 8" (275')

Total maximum equivalent length of increased diameter exhaust vent and intake pipe must not exceed the lengths defined in this manual. Failure to keep the total equivalent length below the maximum lengths determined in this manual will result in faulty boiler operation, substantial property damage, serious personal injury, or death.
G. Exhaust Vent and Intake Pipe Installation

V Series Vent Kit

AL20 4c Vent Terminal

Table 14 - *Friction loss for long radius elbow is 1 foot less. NOTE: Consult Polypropylene venting instructions for friction loss and pressure drop equivalents.

b. For example: If the exhaust vent is 3" in diameter, has two 90o

elbows, and 10 feet of PVC pipe we will calculate:

Exhaust Vent Equivalent Length = (2x5) + 10 = 20 feet. Further, if the 3" intake pipe has two 90o elbows, one 45o elbow,

and 10 feet of PVC pipe, the following calculation applies:

Intake Pipe Equivalent Length = (2x5) + 3 + 10 = 23 feet.

The total equivalent length is 43 feet, well below the maximum of

200 feet.

c. Effort should be made to keep a minimum difference in

equivalent length between the exhaust vent and intake pipe.

3. The minimum total equivalent length is 16 feet.

! WARNING

Failure to install the boiler within the minimum and maximum vent length requirements could result in improper product operation and property damage, serious personal injury, or death.

F. Longer Vent Runs The maximum total equivalent length can be extended by increasing the diameter of both the exhaust vent and intake pipes equally. However, the transitions should begin a minimum of 16 equivalent feet from the boiler. Transitions should always be made in vertical sections of pipe to prevent the condensate from pooling in the vent pipe. The maximum equivalent length for increased diameter vent pipes is 275 ft, which includes 16 ft from with boiler with a transition total of 259 ft upsize piping for longer vent runs.

Figure 12 - Extended Vent Runs

All joints of positive pressure vent systems must be sealed completely to prevent leakage of flue products into the living space. Failure to do so could result in property damage, serious injury, or death.
1. Use only solid PVC, CPVC, or stainless steel pipe or a Polypropylene vent system approved for use with Category IV appliances. ABS pipe material may be used on air inlet piping only.
2. Remove all burrs and debris from joints and fittings. 3. When using PVC or CPVC pipe, all joints must be properly
cleaned, primed, and cemented. Use only cement and primer approved for use with the pipe material. Cement must conform to ASTM D2564 for PVC and ASTM F493 for CPVC pipe. NOTE: DO NOT CEMENT POLYPROPYLENE PIPE. 4. Ensure the vent is located where it will not be exposed to prevailing winds. 5. In all roof venting applications, exhaust discharge must point away from the pitch of the roof. 6. If the exhaust vent is to be terminated in a walled off area (such as a roof with a parapet wall), ensure the exhaust vent terminates a minimum of 10' from nearest wall and extends level with or above the top of the wall. This will ensure flue gas does does not get trapped and possibly recirculated into the intake air pipe, which could contaminate the combustion air. 7. To prevent water leakage, install adequate roof flashing where the pipe enters the roof. 8. If it can be avoided do not locate vent directly over public walkways, driveways, or parking lots in climates where freezing conditions are possible. Condensate could drip and freeze, resulting in a slip hazard or damage to vehicles or machinery. 9. Due to potential moisture build-up, sidewall venting may not be the preferred venting option. To save time and cost, carefully consider venting installation and location. 10. Horizontal lengths of exhaust vent must slope back towards the boiler not less than ¼" per foot to allow condensate to drain from the vent pipe. 11. Do not terminate vent where vapors can accumulate and harm people or pets. 12. When it can be avoided, do not terminate vent where vapors can damage shrubs or plants. Such damages are not covered by product warranty. 13. Moisture in the exhaust gas will condense as it leaves the vent terminal. In cold weather this condensate can freeze on the exterior wall, under the eaves, and on surrounding objects,

LP-550 Rev. 000 Rel. 022 Date 4.2.21

including shrubs. Some discoloration to the exterior of the building is to be expected. However, improper location or installation can result in severe damage to the structure or exterior finish of the building, and increase the opportunity for vent blockages and nuisance shutdowns. 14. In vacant chimney applications, install and seal a rain cap over existing chimney openings. 15. All piping must be fully supported. Use pipe hangers at a minimum of 4 foot intervals to prevent sagging of the pipe where condensate may form. 16. Do not use the boiler to support any piping. 17. Ensure the outdoor exhaust vent and intake pipe terminations are screened to prevent blockage caused by debris or birds. Vent screens are included with this boiler. 18. Maximum Snow Level Determination: These installation instructions reference snow levels in establishing a minimum height for the installation of exhaust vent or air intake terminations. Snow levels shall be determined as follows: a. The installation location may, by ordinance, designate how snow levels are calculated in that location; or b. In the absence of specific ordinances, snow levels shall be calculated from the average monthly maximum depth of snow accumulation as indicated by the National Weather Service's 10 year statistics for the installation location/geographical area. In addition: · Total length of vent piping shall not exceed the limits specified
in this manual. · The vent piping for this direct vented appliance is approved
for zero clearance to combustible construction. · The flue products coming from the exhaust vent will create a
large plume when the heater is in operation. Avoid venting in areas that will affect neighboring buildings or be considered objectionable. · DO NOT locate exhaust vent or intake pipe in a parking area where machinery may damage the pipe. · DO NOT vent near soffit vents, crawl space vents, or other areas where condensate or vapor could create a nuisance or hazard or cause property damage. · DO NOT vent where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valve, or other equipment.

i. Indicates that the piping is used for ventilation, make-up, or combustion air intake, and ii. The letters shall be sized equal to a minimum of the pipe diameter. However, for piping with a diameter exceeding two inches, said lettering does not need to be larger than two inches. The following table lists optional exhaust/intake terminations available from HTP:

Description

Stock Code

3" PVC Concentric Termination Kit

KGAVT0601CVT

3" Stainless Steel Termination Kit

V1000

4" Stainless Steel Termination Kit

V2000

6" Stainless Steel Termination Kit

V3000

3" Polypro Vent Kit Table 16 - Optional Vent Kits

8400P-001

H. Applications 1. Direct Vent Installation of Exhaust and Intake If installing a direct vent option, combustion air must be drawn from the outdoors directly into the boiler intake, and exhaust must terminate outside. There are three basic direct vent options detailed in this manual: 1. Side Wall Venting, 2. Roof Venting, and 3. Unbalanced Venting. Be sure to locate the boiler such that the exhaust vent and intake pipe can be routed through the building and properly terminated. Different vent terminals can be used to simplify and eliminate multiple penetrations in the building structure (see Optional Equipment in Venting Section). The exhaust vent and intake pipe lengths, routing and termination methods must all comply with the methods and limits given in the Venting section of this manual. When installing a combustion air intake from outdoors, care must be taken to utilize uncontaminated combustion air. NOTE: To prevent combustion air contamination, see Table 3.

In the Commonwealth of Massachusetts and as Required by State and Local Codes:
· The vented gas fueled appliance shall not be installed so its combustion, ventilation, or dilution air is obtained from a bedroom or bathroom.
· Signage: Whenever any through-the-wall (horizontal or sidewall) vent is installed less than seven feet above the finished grade, a metal or plastic identification plate shall be permanently mounted to the exterior of the building at a minimum height of eight feet above grade directly in line with the exhaust vent terminal. The sign shall read, in print no less than 0.5 inches in size, "GAS VENT DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS".
· Marking of Exhaust Vent and Intake Pipe: Piping used for ventilation, make-up, or combustion air intake shall be labeled as follows: a. Throughout the entire developed length: i. Labels must be placed every ten feet for exposed/visible piping; or ii. Labels must be placed every three feet for concealed piping. b. At all changes of direction; c. On each side of a penetration through a partition, wall or ceiling; and d. The labels shall be black lettering that:
LP-550 Rev. 000 Rel. 022 Date 4.2.21

Take extra precaution to adequately support the weight of vent pipes terminating through the roof. Failure to properly support roof terminated piping could result in property damage, serious injury, or death.
TWO PIPE ROOF VENTING WITH TEE (INTAKE) AND COUPLING (EXHAUST)

STRAIGHT COUPLING

24" MIN.

INSERT INLET/EXHAUST SCREEN INTO
STRAIGHT COUPLING

TEE
INSERT INLET/EXHAUST SCREENS INTO
EACH END OF TEE

12" OVER MAXIMUM SNOW LEVEL OR 24" WHICHEVER IS GREATER

EXHAUST VENT

Sidewall Venting

with Kit

VENT KIT

MAINTAIN 12" MINIMUM CLEARANCE ABOVE HIGHEST
ANTICIPATED SNOW LEVEL OR GRADE, WHICHEVER IS
GREATER (TYP)
LP-505-A
Sidewall Venting with Concentric Kit
1" MIN.
CONCENTRIC VENT KIT

33
EXTERIOR WALL
EXHAUST
IMPORTANT: INTAKE LEG MUST BE FACING UP
EXHAUST INTAKE

RIGHT SIDE VIEW

INTAKE AIR VENT

LP-445-G 06/23/15

MAINTAIN 12" MINIMUM CLEARANCE ABOVE HIGHEST ANTICIPATED SNOW
LEVEL OR GRADE, WHICHEVER IS GREATER (TYP.)

CONCENTRIC VENT KIT
Roof Venting with Concentric Vent Kit

LP-505-C 05/26/15
12" OVER MAXIMUM SNOW LEVEL OR 24" - WHICHEVER IS GREATER

Figure 13 - Two Pipe Roof and Sidewall Venting

LP-505-C 05/26/15

NOTE: EXTENDED VENT RUNS WHEN TRANSITIONING TO A LARGER DIAMETER MUST ALWAYS TAKE PLACE IN A VERTICAL POSITION TO PREVENT CONDENSATE BLOCKAGE

Figure 14 - Venting with Optional Kits (NOT INCLUDED WITH THE BOILER)
NOTE: These drawings are meant to demonstrate system venting only. The installer is responsible for all equipment and detailing required by local codes.

All vent pipes must be glued, properly supported, and the exhaust pitched a minimum of 1/4" per foot back to the boiler to allow drainage of condensate. When placing support brackets on vent piping, the first bracket must be within 1 foot of the boiler and the balance of 4 foot intervals on the vent pipe. Venting must be readily accessible for visual inspection from the first three feet from the boiler.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

34
Snorkel Venting (Two Pipe Sidewall Venting Terminations Beneath an Overhang)

Venting Below Grade For installations that exit the wall below grade: 1. Excavate the site to a point where the pipes are to exit as shown
in Figure 16. 2. Ensure the wall is fully sealed where the pipes penetrate. 3. The exhaust vent / air intake piping MUST be secured to the side
of the building above grade, as shown, to provide rigidity. 4. Ensure that the exhaust vent / air intake clearances are maintained.
Exhaust
Air-inlet

Exhaust

Wall Brackets
B

Intake

Figure 16 - Venting Below Grade

Outdoor Venting

Vent piping outside the building is permitted under the following con-

ditions:

1. The maximum length outside the building is 20 feet (6.1 m). Note

that outdoor length must be included in the overall vent length

calculation.

2. All normal termination clearances are maintained.

3. The pipe is supported every 24" (610 mm).

4. The exhaust and air intake are sloped back to the boiler 1/2"

elevation for every linear foot (13 mm for every linear 305 mm).

LP-700-C 05/30/19
Figure 15 - Two Pipe Sidewall (Horizontal Snorkel) Venting NOTES: A. For every 1" of overhang, the exhaust vent must be located 1"
vertical below the overhang (12" minimum). Overhang means top of building structure (roof ) and not two adjacent walls (corner of building). B. Maintain minimum separation between exhaust vent and air intake sidewall terminations, as required by local codes. C. Maintain 12" minimum clearance above highest anticipated snow level or grade (whichever is greater). D. The exhaust vent must extend a minimum of 12" to a maximum of 24" beyond the building. NOTE: These drawings are meant to demonstrate system venting only. The installer is responsible for all equipment and detailing required by local codes.

Gas Vent Directly Below Keep Free of Obstructions
Exhaust Vent
Maximum of 20 ft [6.1 m] is permitted for piping outside a building.
Figure 17 - Outdoor Venting

LP-550 Rev. 000 Rel. 022 Date 4.2.21

35
Figure 18 - Unbalanced Venting - Roof Exhaust and Sidewall Intake NOTE: These drawings are meant to demonstrate system venting only. The installer is responsible for all equipment and detailing required by local codes. All vent pipes must be glued, properly supported, and the exhaust pitched a minimum of 1/4" per foot back to the boiler to allow drainage of condensate. When placing support brackets on vent piping, the first bracket must be within 1 foot of the boiler and the balance of 4 foot intervals on the vent pipe. Venting must be readily accessible for visual inspection from the first three feet from the boiler. An unbalanced vent system can be installed ONLY when the exhaust is in the vertical position. Failure to do so could result in serious personal injury or death.
LP-550 Rev. 000 Rel. 022 Date 4.2.21

2. Venting Through an Existing System
This boiler may be vented through an existing unused vent system. The inner diameter of the existing vent system is utilized for the combustion air source. Two methods have been approved for such venting: Concentric Venting Through an Existing System and Venting as a Chase.

Vent / Air Intake Size Minimum Existing Vent / Chase Size

Table 17 - Minimum Existing Vent / Chase Sizing

Concentric Venting Through an Existing System NOTE: The following instructions refer only to venting through an existing vent system, and not to venting with HTP's optional concentric vent kits. Refer to Concentric Vent Kit installation manual (LP-166) for further information on venting with the optional concentric vent kits. Concentric venting through an existing system must run vertically through the roof. See Table 17 for proper minimum vent sizing. Use only the approved venting materials specified in Table 12 for piping the system. All instructions listed in this Venting section apply. See Figures 19-1 and 19-2 for venting demonstrations.

Do not install the boiler into a common existing vent with any other appliance. This will cause flue gas spillage or boiler malfunction, resulting in substantial property damage, serious personal injury, or death.
Contractors must check state and local codes before installing through an existing vent opening. State and local codes always take precedence over manufacturer's instructions. Failure to check state and local codes before installing through an existing opening could result in property damage and add significantly to installation costs. If an existing venting system is converted for use with this boiler, the installer must ensure that the existing venting system is clean and free from particulate contamination that could damage the boiler. Failure to do so could result in property damage and boiler failure. Such failure IS NOT covered under warranty.

The upper and lower vent terminations as well as all joints in the venting system must be properly sealed to ensure that all combustion air is drawn properly and exhaust does not leak from the system. Failure to properly seal the venting system will result in property damage, serious personal injury, or death.
Chase Venting Through an Existing System When venting as a chase, follow all instructions included in this Venting section, including those in the previous Concentric Venting Through an Existing System section. See Figure 19-3 for chase venting demonstration.

Concentric Venting through an Existing System

1
SEAL

EXHAUST

Concentric Venting through an Existing System

EXHAUST

SEAL

Chase Venting through an Existing System 3 EXHAUST

24" INTAKE

EXISTING

COMBUSTION AIR EXISTING
SEAL

Intake

COMBUSTION AIR
AIR INTAKE w/SCREEN 12" MIN.

EXISTING VENT

SEAL

Exhaust

Exhaust Intake

AIR INTAKE (w/SCREEN)

SEAL

SEALED CAP

SEAL

SEALED CAP

CAP

SEAL

LP-325-MM 03/15/12

Figure 19 - 1, 2 - Concentric Venting Through an Existing System, 3, Chase Venting Through an Existing System

LP-325-NN 07/22/13

NOTE: These drawings are meant to demonstrate system venting only. The installer is responsible for all equipment and detailing required

by local codes.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

3. Power Venting, Indoor Combustion Air in Confined or Unconfined Space This boiler requires fresh, uncontaminated air for safe operation and must be installed in a mechanical room where there is adequate combustion and ventilating air. NOTE: To prevent combustion air contamination, see Table 3. Combustion air from the indoor space can be used if the space has adequate area or when air is provided through a duct or louver to supply sufficient combustion air based on the boiler input. Never obstruct the supply of combustion air to the boiler. If the boiler is installed in areas where indoor air is contaminated (see Figure 20) it is imperative that the boiler be installed as direct vent so that all combustion air is taken directly from the outdoors into the boiler intake connection. Unconfined space is space with volume greater than 50 cubic feet per 1,000 Btu/hour (4.8 cubic meters per kW) of the total input rating of all fuel-burning appliances installed in that space. Rooms connected directly to this space, through openings not furnished with doors, are considered part of the space. Confined space is space with volume less than 50 cubic feet per 1,000 Btu/hour (4.8 cubic meters per kW) of the total input rating of all fuel-burning appliances installed in that space. Rooms connected directly to this space, through openings not furnished with doors, are considered part of the space. When drawing combustion air from inside a conventionally constructed building to a confined space, such space should be provided with two permanent openings: one located 6" (15 cm) below the space ceiling, the other 6" (15cm) above the space floor. Each opening should have a free area of one square inch per 1,000 Btu/hr (22cm2/kW) of the total input of all appliances in the space, but not less than 100 square inches (645cm2). If the confined space is within a building of tight construction, air for combustion must be obtained from the outdoors as outlined in the Venting section of this manual. See Figure 21.

Indoor Combustion Air (Single Pipe)
ROOM OPENING
ROOM OPENING
Outdoor Combustion Air (Single Pipe)
UPPER AIR DUCT

EXHAUST
6"
Boiler, Water Heater, or Appliance
6"
EXHAUST

37
LP-325-S 09/29/11

LOWER AIR DUCT

Boiler, Water Heater, or Appliance

Figure 21 - Indoor and Outdoor Combustion Air - Single Pipe

LP-325-T 8/5/2010

DO NOT INSTALL WATER HEATER,
BOILER, OR APPLIANCE NEAR DRYER
Figure 20 - Do Not Place Appliance Near Dryer

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 6 - Condensate Removal
CAUTION
This condensing high efficiency boiler has a condensate removal system. Condensate is water vapor derived from combustion products, similar to that produced by an automobile when it is initially started. It is very important that the condensate line is sloped down away from the boiler and to a suitable drain. The condensate line must remain unobstructed. If allowed to freeze in the line or obstructed in any other manner, condensate can exit from the boiler tee, resulting in potential water damage to property. When installing a condensate pump, select one approved for use with condensing boilers and furnaces. The condensate pump should have an overflow switch to prevent property damage from spillage. Condensate from the boiler will be slightly acidic (pH from 3.2 to 4.5). Check with your local gas company to determine if combustion condensate disposal is permitted in your area. Install a neutralizing filter if required by local codes.

9. Route the drain line to a nearby floor drain, laundry tub, or condensate pump. If the boiler condensate outlet is lower than the drain, you must use a condensate removal pump (kit p/n 554200 available from HTP). NOTE: If a nearby laundry tub is used as a disposal for waste water from the washing machine, draining the condensate into this tub allows the soapy water discharge to neutralize the acidic condensate. 10. An error will appear on the boiler display if condensate line is blocked. The boiler will not operate with a blocked condensate line. It is extremely important to have this condition repaired by a qualified service technician. 11. Damages due to frozen or blocked condensate lines or leaks ARE NOT covered by warranty. NOTE: To clean out condensate trap, see Maintenance section.

Is is very important that condensate piping be no smaller than 3/4". Use a tee at the condensate connection with a branch vertically up and open to the atmosphere to prevent a vacuum that could obstruct the flow of condensate from the boiler. To prevent sagging and maintain pitch, condensate piping should be supported with pipe supports.

NOTES: 1. Due to its efficient design, the boiler produces condensate (water) as a normal by-product. This condensate is acidic, with a pH level between 2 and 4.5. This condensate must be drained away from the boiler and disposed in accordance with all local regulations. 2. The condensate line should be as short as possible and must be pitched at least ¼" per foot to properly drain. If this cannot be done, increase the condensate line and place a tee in the line to properly reduce vacuum lock in the drain line. Tees should be placed after the condensate neutralizer (if used). 3. Use corrosion-resistant materials to drain condensate. Use flexible plastic hose or tube, PVC, or CPVC pipe. PVC or CPVC pipe must comply with ASTM D1785, F441, or D2665. Cement must comply with ASTM D2564 for PVC pipe or F493 for CPVC pipe. For Canadian applications, use CSA or ULC certified flexible tube, PVC or CPVC pipe, fittings, and cement. 4. If using flexible tube, place an overflow tee in the tube line to prevent condensate backing up into the boiler if the tube should kink. Ensure the overflow tee is positioned near a drain or in a location that will not damage the surrounding area. 5. Do not reduce the size of the condensate line. The line must at minimum equal the diameter of the line included with the appliance. 6. A frozen condensate line could result in a blocked vent condition. It is very important to protect the condensate line from freezing temperatures or any type of blockage. In installations that may encounter sustained freezing conditions, the use of heat tape is recommended to avoid freezing of the condensate line. Longer condensate runs are more prone to freezing. 7. Support of the condensate line may be necessary to avoid blockage of the condensate flow. 8. Local building codes may require an in-line neutralizer to be installed (not included) to treat the condensate. See Figure 22. If required by local authorities, a condensate filter of lime crystals, marble, or phosphate chips will neutralize slightly acidic condensate (Part # 7450P-212 for 80/110/150/220/299/301 Models, Part # 7350P611 for 399 Models). Follow all the installation instructions included with the neutralizer. If a neutralizer is installed, periodic replacement of the limestone (or neutralizing agent) will be required. The rate of depletion of the limestone varies with usage of the boiler. During the first year of boiler operation, check the neutralizer every few months for depletion.

Figure 22 - Condensate Piping
Power to the optional condensate pump is continuous. When the boiler is powered off the condensate pump will remain on. It is important to remember to turn off the condensate pump when powering down the boiler. Failure to do so could result in property damage, severe personal injury, or death.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 7 - Wiring

! WARNING
Install wiring and electrically ground boiler in accordance with the authority having jurisdiction or, in the absence of such an authority, follow the National Electrical Code, NFPA 70, and/or CSA C22.1 Electrical Code-Part 1 in Canada. Failure to follow all applicable local, state, and national regulations, mandates, and building supply codes for guidelines to install the electrical power supply could result in property damage, serious personal injury, or death.
Jumping out control circuits or components WILL VOID product warranty and can result in property damage, personal injury, or death. It is of extreme importance that this unit be properly grounded. It is very important that the building system ground is inspected by a qualified electrician prior to making this connection. Electrical power must only be turned on when the boiler is completely filled with cold water. Failure to follow these instructions could result in component or product failure, serious injury, or death.
ELECTRICAL SHOCK HAZARD To ensure safety, turn off electrical power supply at service entrance panel before making any electrical connections to avoid possible electric shock hazard. Failure to do so could result in property damage, serious personal injury, or death.
! CAUTION
Label all wires prior to disconnecting them when servicing the boiler. Wiring errors can cause improper and dangerous operation. Failure to follow these instructions may result in property damage or personal injury.
CAUTION
Wiring must be NEC Class 1. If original wiring supplied with the boiler must be replaced, use only TEW 105 oC wire or equivalent. Boiler must be electrically grounded as required by the National Electrical Code, ANSI/NFPA 70 - Latest Edition.

A. Installation Must Comply With 1. National Electrical Code and any other national, state, provincial, or local codes or regulations. 2. In Canada, CSA C22.1, Canadian Electrical Code Part 1, and any local codes.

B. Field Wiring Terminations

All connections

made to the

boiler in the field

are done inside

the electrical

junction

box

located on the left

side of the unit.

Multiple knockout

locations are

available to route

field wires into

and out of the

electrical junction

box.

Figure 23 - Knockout Locations

C. Field Wiring The control used in the boiler is capable of directly controlling 2 pumps in standard mode and 3 pumps when configured as a cascade master boiler. As a standard unit, each pump can provide a maximum of 2 amps at 120 volts. If a pump requires more than this amount of power, an external contactor or motor starter is needed.

The electrical junction box has separate, clearly marked terminal strips for line voltage and low voltage wiring. Special jacks are provided for trouble-free cascade system wiring using standard CAT3 or CAT5 patch cables.
D. Line Voltage Wiring for Standard Boiler NOTE: A termination plug is included in the CAT 3 / CAT 5 Bus Connection Point, labeled J3 in Figure 24. DO NOT REMOVE THIS PLUG! Doing so will affect boiler operation and void warranty. 1. Connect 120V / 60Hz / 15 AMP incoming power wiring to the line voltage terminal strip in the electrical junction box at terminals 120V, Neutral, Ground (shown in Figure 24). 2. A line voltage fused disconnect switch may be required, externally mounted and connected according to local codes that may apply. 3. Connect the boiler pump as shown in Figure 24 to the terminals marked 1 (HOT), 2 (NEUT), and 3 (GND). The connections shown are suitable for a maximum continuous pump draw of 2 amps at 120 volts. If the pump requires more current or voltage than the 120 volts supplied, an external motor starter or contactor will be required. 4. If using DHW, connect the domestic hot water pump to the terminals marked 4 (DHW HOT), 5 (DHW NEUT), 6 (DHW GND). The connections shown are suitable for a maximum continuous pump draw of 2 amps at 120 volts. If a pump requires more current or voltage than the 120 volts supplied, an external motor starter or contactor will be required.
E. Alarm Connections The control includes a dry contact alarm output. This is an SPDT circuit, rated at 5 amps at 120 volts. This contact can be used to activate an alarm light or bell or notify a building management system if the boiler goes into a lockout condition. The circuit between the ALARM COM and NC terminals is closed during normal operation and the circuit between ALARM COM and NO is open during normal operation. The connections depicted in Figure 24 show two 120 volt lights connected to the alarm terminals. One light will be on when the boiler is in normal mode and the other light will be on when the boiler is in lockout mode.
F. Low Voltage Connections for Standard Boiler 1. All low voltage cables should enter the electrical junction box through the provided knock out holes as shown in Figure 23. 2. Connect all low voltage field devices to the low voltage terminal strip located in the electrical junction box.
G. Thermostat 1. Connect the room thermostat to the terminals marked THERMOSTAT in the electrical junction box (see Figures 24 and 26). Alternately, any dry contact closure across these terminals will cause the boiler to run. Take caution to ensure neither of the terminals becomes connected to ground. 2. Mount the thermostat on an inside wall as central as possible to the area being heated, but away from drafts or heat producing devices such as television sets that could influence the ability of the thermostat to measure room temperature. 3. If the thermostat is equipped with an anticipator and it is connected directly to the boiler, the anticipator should be set at .1 amps. If the thermostat is connected to other device(s), the anticipator should be set to match the power requirements of the device(s). See the instruction manual of the connected device(s) for further information.
H. Outdoor Sensor There is no connection required if an outdoor sensor is not used in the installation. 1. Use a minimum 22 AWG wire for runs of 100 feet or less and minimum 18 AWG wire for runs of up to 150 feet. 2. Mount the outdoor sensor on an exterior surface of the building, preferably on the north side in an area that will not be affected by direct sunlight and will be exposed to varying weather conditions. NOTE: For correct mounting procedures, follow instructions provided with the sensor.

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NOTE: For correct mounting procedures, follow instructions provided with the sensor. NOTE: If sensor wires are located in an area with sources of potential electromagnetic interference (EMI), the sensor wires should be shielded, or the wires routed in a grounded metal conduit. If using shielded cable, the shielding should be connected to the common ground of the boiler.
I. Indirect Sensor There is no connection required if an indirect water heater is not used in the installation. 1. The boiler will operate an indirect fired water heater with either a thermostat type aquastat installed in the indirect tank or an HTP 7250P-325 tank sensor. When a tank sensor is used, the boiler control will automatically detect its presence and a demand for heat from the indirect water heater will be generated when the tank temperature falls below the user set point by more than the user selectable offset. The demand will continue until the sensor measures that the indirect water heater temperature is above the set point. 2. Connect the indirect sensor (7250P-325) to the terminals marked DHW SENSOR (shown in Figures 24 and 26) in the electrical junction box.
Failure to use the correct sensor may result in tank temperature being either above or below set point, and could result in decreased performance, substantial property damage, or heightened risk of injuries due to scalds.
Caution should be used to ensure neither of these terminals becomes connected to ground. Failure to do so can result in property damage, personal injury, or death.

Figure 24 - Control Wiring

NOTE: If sensor wires are located in an area with sources of potential electromagnetic interference (EMI), the sensor wires should be shielded, or the wires routed in a grounded metal conduit. If using shielded cable, the shielding should be connected to the common ground of the boiler.

J. Optional 0-10 Volt Building Control Signal 1. A signal from a building management system may be connected to the boiler to enable remote control. This signal should be a 0-10 volt positive-going DC signal. When this input is enabled using the installer menu, a building control system can be used to control the set point temperature of the boiler. The control interprets the 0-10 volt signal as follows; when the signal is between 0 and 1.5 volts, the boiler will be in standby mode, not firing. When the signal rises above 1.5 volts, the boiler will ignite. As the signal continues to rise towards its maximum of 10 volts, the boiler will increase in set point temperature. See Part 10 for details on the setting of function 16. 2. Connect a building management system or other auxiliary control signal to the terminals marked 16, 0-10 VOLT + and 17, 0-10 VOLT in the electrical junction box (shown in Figure 24). Caution should be used to ensure that the 0-10 VOLT + connection does not become connected to ground. 3. See Function 17 this manual to program the 0-10 volt signal. NOTE: When a 0-10 volt building management system is installed, the return sensor temperature cannot be monitored through the appliance display.

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K. Optional Low Water Cut-Off (LWCO) Kit If an optional Low Water Cut-Off (LWCO) Kit is used, the LWCO probe should be mounted into the fitting provided in the outlet combination fitting. Follow the complete instructions included in the kit for proper installation.
L. Wiring of Cascade System Communication Bus 1. A Cascade Bus Termination Plug has been installed on the customer connection board of this boiler. The purpose of this plug is to stabilize communication between multiple boilers and reduce electrical "noise". See Figures 25 and 26 for Cascade Bus Termination Plug installation detail. 2. Use standard CAT3 or CAT5 computer network patch cables to connect the communication bus between each of the boilers. These cables are readily available at any office supply, computer, electronic, department or discount home supply store in varying lengths. If you possess the skills you can also construct custom length cables. 3. It is recommended to use the shortest length cable that will reach between the boilers and create a neat installation. Do not run unprotected cables across the floor where they may become wet or damaged. Avoid running communication cables parallel and close to or against high voltage (120 volt or greater) wiring. HTP recommends that the maximum length of communication bus cables not exceed 200 feet. 4. Route the communication cables through one of the knockouts in the cabinet. 5. Connect the boilers in a daisy chain configuration as shown below. It is best to wire the boilers using the shortest wire runs rather than trying to wire them in the order that they are addressed. The communication bus jacks on the customer connection panel are interchangeable so you can use either one or both in any order to connect the cable. If you have connected the boilers to each other properly, there will be no open communication connection ports.
M. Cascade Master Pump and Sensor Wiring 1. Connect the system pump hot wire to the terminal marked 7 (SYS PUMP). 2. Connect the system pump neutral to the 8 (SYS NEUT) terminal and the pump ground wire to the 9 (SYS GND) terminal. 3. Connect the boiler pump to the terminals marked 1 (BOILER HOT), 2 (BOILER NEUT), and 3 (BOILER GND). 4. Connect the system pipe sensor to the terminals marked 18 and 19 (SYS SENSOR). 5. Connect the outdoor sensor (if used) to the terminals marked 12 and 13 (OUTDOOR SEN). 6. Connect the signal to start the system to the terminals marked 14 and 15 (THERMOSTAT). NOTE: This signal can come from a room thermostat or a dry contact closure. No power of any voltage should be fed into either of these terminals.

N. Cascade Follower Pump and Sensor Wiring 1. Connect the boiler pump to the terminals labeled 1 (HOT), 2 (NEUT), and 3 (GND). 2. An alarm bell or light can be connected to the alarm contacts of the follower boiler. The normally closed alarm contact may be used to turn a device off if the boiler goes into lockout mode. The alarm contacts are rated 5 amps at 120 VAC. To connect an alarm device, connect the power for the device to the ALARM COM terminal. Connect the alarm device hot wire to the ALARM NO terminal. Connect the neutral or return of the alarm device to the neutral or return of the power for the alarm device. To connect a device that should be powered off during a boiler lockout condition, follow the same instructions as above except use the ALARM NC terminal rather than the ALARM NC terminal. Note that in a cascade system the alarm output of the boiler addressed as #1 will also be active if the master boiler has a lockout condition. The alarm output of boilers addressed as 2-7 will only activate an alarm if a lockout condition occurs on that specific boiler.
O. Variable Speed Pumping Variable speed pump support is available on the primary loop of all models manufactured after 11/15/2016. This feature controls pump speed via an analog 0-10VDC signal supplied via the 0-10VA connection on the Customer Connection Board. When this feature is in use, an installer selected Delta T is maintained with the Supply and Return sensors, increasing efficiency and providing better system temperature control. When the difference between the Supply and Return temperatures is greater than the desired setting, the pump will increase speed and flow to compensate. Conversely, if the Delta T is less than the desired setting, the pump will decrease speed and flow to compensate. NOTE: This feature may be used in Primary / Secondary piping arrangements ONLY!
Variable Speed Pumping Wiring: 1. Connect the boiler pump as shown in Figure 24 to the terminals marked 1 (HOT), 2 (NEUT), and 3 (GND). The connections shown are suitable for a maximum continuous pump draw of 2 amps at 120 volts. If the pump requires more current or voltage than the 120 volts supplied, an external motor starter or contactor will be required. 2. Connect the 0-10v input wires on the variable speed pump to the 0-10v output on J9 of the customer connection board. Connect the positive pump input wire to J9-24, and the negative wire to J9-25. NOTE: When making wiring connections, ensure proper polarity or the system will not operate properly.

Figure 25 - Cascade Termination Plug Detail

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Figure 26 - Cascade Master and Follower Wiring
LP-550 Rev. 000 Rel. 022 Date 4.2.21

Figure 27 - Internal Connection Diagram

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Part 8 - Gas Connections
! WARNING
FIRE AND/OR EXPLOSION HAZARD To avoid serious injury or death, the gas line installation and the gas line inlet pressure test must be done by a licensed professional.
It is very important that the boiler is connected to the type of gas noted on the rating plate. "LP" for liquefied petroleum, propane gas, or "NG" for natural gas. Do not do a gas conversion without an approved gas conversion kit (not included). Prior to turning the gas on, all gas connections must be approved by the local gas supplier or utility, in addition to the governing authority.
Make sure the gas line pressures are within normal limits. Pressures outside normal limits can result in poor performance and hazardous operating conditions, property damage, personal injury, or death.
UL recognized fuel gas detectors are recommended in all enclosed propane and natural gas applications where there is a potential for an explosive mixture of fuel gas to accumulate. The installation of these detectors should be made in accordance with the detector manufacturer's recommendations, and/or local laws. Failure to install fuel gas detectors in these applications could result in fire, explosion, property damage, severe personal injury, or death.
Never use an open flame (match or lighter) to check for gas leaks. Use a soapy solution to test connection.
Do not use Teflon tape on gas line pipe thread. Use a pipe compound rated for use with natural gases. Apply sparingly on male pipe ends, leaving the two end threads bare and flow unobstructed.
Support gas supply piping with hangers, not by the boiler or its accessories. The boiler gas valve and blower will not support the weight of the piping. Make sure the gas piping is protected from physical damage and freezing, where required.
Failure to follow these instructions could result in property damage, gas leakage, fire, explosion, serious personal injury, or death.

A. Gas Piping 1. Run the gas supply line in accordance with all applicable codes. 2. Locate and install manual shutoff valves in accordance with state and local requirements. 3. In Canada, the Manual Shutoff must be identified by the installing contractor. 4. It is important to support gas piping as the unit is not designed to structurally support a large amount of weight. 5. Purge all gas lines thoroughly to avoid start up issues with air in the lines. 6. Sealing compound must be approved for gas connections. Care must be taken when applying compound to prevent blockage or obstruction of gas flow which may affect the operation of the unit.
Figure 28 - Gas Connection

The gas supply shall have a maximum inlet pressure of less than 14" w.c. (3.5 kPa), and a minimum of 3.5" w.c. (.87 kPa). The entire piping system, gas meter and regulator must be sized properly to prevent pressure drop greater than 0.5" (.12 kPa) as stated in the National Fuel Gas Code. This information is listed on the rating label.

NOTICE

Do not operate the boiler on Natural Gas or LP gas with average sulfur rates greater than 30 mg/m3. Doing so could result in improper product operation and failure, and WILL VOID the boiler warranty.

The gas connection on the boiler is 3/4" for 80/110/150 models and 1" for 220/299/301/399 models. It is mandatory that this fitting is used for connection to a field fabricated drip leg as shown in the illustratioN per the National Fuel Gas Code. You must ensure that the entire gas line to the connection at the boiler is no smaller than the unit supplied connection. Once all inspections have been performed, the piping must be leak tested. If the leak test requirement is a higher test pres¬sure than the maximum inlet pressure, you must isolate the boiler from the gas line. In order to do this, shut the gas off using factory and field-installed gas cocks. This will prevent high pressure. Failure to do so may damage the gas valve. In the event the gas valve is exposed to a pressure greater than ½ PSI, 14" w.c. (3.5 kPa), the gas valve must be replaced. Never use an open flame (match, lighter, etc.) to check gas connections.

Use two wrenches when tightening gas piping at the boiler: One to prevent the boiler gas line from turning. Failure to prevent the boiler gas connection from turning could result in damage to the gas line components, substantial property damage, severe personal injury, or death.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

CSA or UL listed flexible gas connections can be used when installing the boiler. Flexible gas connections have different capacities and must be sized correctly for the connected boiler firing rates. Consult with the flex line supplier to assure the line size is adequate for the job. Follow local codes for proper installation and service requirements.
B. Additional Precaution for Excess Flow Valve (EFV) If an excess flow valve (EFV) is in the gas line, check the manufacturer's minimum and maximum flow capacity ratings. An improperly sized EFV will not allow for a full flow of gas to the boiler and will cause the boiler to malfunction. See Figure 29.
Table 18 - Gas Pipe Sizing / BTU's per Hour

Ensure the pressure tap screw is properly tightened to prevent gas leaks. Failure to do so could cause substantial property damage, severe personal injury, or death.

Figure 29 - Excess Flow Valve (EFV)
! WARNING
When performing a pressure test on the gas line piping, be sure the boiler is disconnected or isolated if the test pressure is expected to exceed 1/2 PSI (14" WC), as damage to the gas valve could occur. Such damage could result in fire, property damage, serious personal injury, or death.
C. Check Inlet Gas Pressure The gas valve is equipped with an inlet gas pressure tap that can be used to measure the gas pressure to the unit. To check gas pressure, perform the steps listed below: 1. IMPORTANT! Before you connect to the inlet pressure, shut off the gas and electrical power to unit. 2. Loosen the pressure tap with a small screwdriver. Refer to Figure 30 for location. 3. Each unit is equipped with a needle valve that will accept a 5/16 ID hose to connect to a digital manometer or liquid gauge to measure incoming pressure from 0-35" w.c. See Figure 30. 4. Turn on the gas and power up the unit. 5. Put the unit into manual test mode (details on test mode are in Part 10). In test mode, monitor pressure to assure it does not drop below 1 inch from its idle reading. If gas pressure is out of range or pressure drop is excessive, contact the gas utility, gas supplier, qualified installer, or service agency to determine correct action that is needed to provide proper gas pressure to the unit. If Gas Pressure is within normal range proceed to Step 6. 6. Exit test mode, then turn power off and shut off gas supply at the manual gas valve before disconnecting the hose from the gas monitoring device. Tighten screw on the pressure tap and turn gas on. Check for leaks with soapy solution. Bubbles will appear on the pipe to indicate a leak is present.

The gas piping must be sized for the proper flow and length of pipe to avoid pressure drop. The gas meter and regulator must be properly sized for the total gas load. If you experience a pressure drop greater than 1" w.c. (.87 kPa), the meter, regulator or gas line may be undersized or in need of service. You can attach a manometer to the incoming gas drip leg after removing the cap. The gas pressure must remain between 3.5" (.87 kPa) and 14" (3.5 kPa) during stand-by (static) mode and while in operating (dynamic) mode. If an in-line regulator is used, it must be a minimum of 10 feet from the boiler. It is very important that the gas line is properly purged by the gas supplier or utility. Failure to properly purge the lines, or improper line sizing, will result in ignition failure. This problem is especially noticeable in NEW LP installations and empty tank situations. This situation can also occur when a utility company shuts off service to an area to provide maintenance to their lines. This gas valve must not be replaced with a conventional gas valve under any circumstances.
DO NOT adjust or attempt to measure gas valve outlet pressure. The gas valve is factory-set for the correct outlet pressure and requires no field adjustment. Attempts by the installer to adjust or measure the gas valve outlet pressure could result in damage to the valve and cause substantial property damage, severe personal injury, or death.
Ensure that the high gas pressure regulator is as least 6 10 feet upstream of the appliance. Failure to do so could result in substantial property damage, severe personal injury, or death.

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46 D. Boiler Gas Valve

Figure 30 - Gas Valve

Do not do a gas conversion on this boiler without an officially approved conversion kit and instructions supplied by HTP. Failure to use a conversion kit when converting the boiler to fire on Natural or Propane gas will result in extremely dangerous burner operation, leading to fire, explosion, severe personal injury, or death.

Strain on the gas valve and fittings may result in vibration, premature component failure and gas leakage, and result in fire, explosion, property damage, severe personal injury, or death.
Adjustments to the throttle screw or offset may only be made by a qualified gas technician using a calibrated combustion analyzer capable of measuring CO2 and CO. Failure to follow this instruction could result in fire, explosion, property damage, severe personal injury, or death.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 9 - Start-Up Preparation
Thoroughly clean and flush any system that has used glycol before installing the boiler. Provide the customer with a material safety data sheet (MSDS) on the fluid used.

instructions. NOTE: Boiler failure due to improper water chemistry is not covered by warranty.
B. Check for Gas Leaks

A. Check / Control Water Chemistry
Chemical imbalance of your water can cause severe damage to your boiler and associated equipment, and may also affect efficiency. You may have to have your water quality professionally analyzed to determine whether you need to install a water softener. It is important that the water chemistry on both the domestic hot water and central heating sides are checked before installing the boiler, as water quality will affect the reliability of the system. Outlined below are those water quality parameters which need to be met in order for the system to operate efficiently for many years. Failure of a heat exchanger due to lime scale build-up on the heating surface, low pH or other imbalance IS NOT covered by the warranty.
To assure extended service life, it is recommended to test water quality prior to installation. Listed below are some guidelines.
Do not use petroleum-based cleaning or sealing compounds in the boiler system. Damage to elastomer seals and gaskets in the system could occur, resulting in substantial property damage.
· Water pH between 6.5 and 8.5 · Maintain water pH between 6.5 and 8.5. pH levels below 6.5 can cause an increase in the rate of corrosion. pH of 8.5 or higher can potentially cause lime scale build-up
· Hardness less than 7 grains (120 mg/L) · Hardness levels above the required amounts can lead to lime scale build-up throughout the system. Water below 5 grains/gallon (85 mg/L) may be over softened.
· Chloride concentration less than 100 ppm (mg/L) · Do not fill appliance or operate with water containing chlorides in excess of 100 ppm (mg/L).
· Total Dissolved Solids (TDS) less than 500 ppm (mg/L) · If using softened water to fill the appliance, it is still possible to have high TDS. This water can be corrosive. Consult local water treatment companies for other treatment solutions to reduce this affect.
Clean system to remove sediment* 1. You must thoroughly flush the system (without boiler connected) to remove sediment. The high-efficiency heat exchanger can be damaged by buildup or corrosion due to sediment. 2. For zoned systems, flush each zone separately through a purge valve. (If purge valves and isolation valves are not already installed, install them to properly clean the system.) 3. Flush system until water runs clean and you are sure piping is free of sediment. *NOTE: It is recommended you clean heat exchanger at least once a year to prevent lime scale buildup. Follow the maintenance procedure to clean the heat exchanger in the Maintenance Section of this manual. Test/replace freeze protection fluid 1. For systems using freeze protection fluids, follow fluid manufacturer's instructions to verify inhibitor level and that other fluid characteristics are satisfactory. 2. Freeze protection fluid must be replaced periodically due to degradation of inhibitors over time. Follow all fluid manufacturer

Before starting the boiler, and during initial operation, smell near the floor and around the boiler for gas odorant or any unusual odor. Remove boiler front door and smell interior of boiler enclosure. Do not proceed with startup if there is any indication of a gas leak. Repair any leaks at once.
PROPANE BOILERS ONLY The propane supplier mixes an odorant with the propane to make its presence detectable. In some instances the odorant can fade, and the gas may no longer have an odor. Before startup (and periodically thereafter), have the propane supplier verify the correct odorant level in the gas.
C. Freeze Protection (When Used)
NEVER use automotive or standard glycol antifreeze. Do not use ethylene glycol made for hydronic systems. Use only freezeprotection fluids certified by fluid manufacturer as suitable for use with stainless steel boilers, verified in the fluid manufacturer's literature. Thoroughly clean and flush any system that has used glycol before installing the new boiler. Provide the boiler owner with a material safety data sheet (MSDS) on the fluid used. 1. Determine the freeze protection fluid quantity using total system water content following the fluid manufacturer's instructions. Remember to include expansion tank water content. 2. Local codes may require back flow preventer or actual disconnect from city water supply. 3. When using freeze protection fluid with automatic fill, install a water meter to monitor water makeup. Freeze protection fluid may leak before the water begins to leak, causing concentration to drop, reducing the freeze protection level.
D. Fill and Test Water System
Ensure the boiler is full of water before firing the burner. Failure to do so will damage the boiler. Such damage IS NOT covered by warranty, and could result in property damage, severe personal injury, or death.
1. Fill the system only after ensuring water chemistry meets the requirements listed in this manual. 2. Close the manual and automatic air vents and boiler drain valve. 3. Fill to the correct system pressure. Correct pressure will vary with each application.
a. Typical cold water fill pressure for a residential system is 12 psi. b. Pressure will rise when boiler is turned on and system water temperature increases. Operating pressure must never exceed the relief valve pressure setting. 4. At initial fill and during boiler startup and testing, check system thoroughly for leaks. Repair all leaks before proceeding further.
Eliminate all system leaks. Continual fresh make-up water will reduce boiler life. Minerals can build up in the heat exchanger, reducing heat transfer, overheating the heat exchanger and causing heat exchanger failure. 5. The system may have residual substances that could affect water chemistry. After the system has been filled and leak tested, verify that water pH and chloride concentrations are acceptable by sample testing.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

It is important to purge the system of air to avoid damage to the boiler.
E. Purge Air from Water System Purge air from the system:
a. Connect a hose to the purge valve and route hose to an area where water can drain and be seen. b. Close the boiler or system isolation valve between the purge valve and fill connection to the system. c. Close zone isolation valves. d. Open quick-fill valve on cold water make-up line. e. Open purge valve. f. Open the isolation valves one zone at a time. Allow water to run through the zone, pushing out the air. Run water until no noticeable air flow is present. Close the zone isolation valves and proceed with the next zone. Follow this procedure until all zones are purged. g. Close the quick-fill water valve and purge valve and remove the hose. Open all isolation valves. Watch the system pressure rise to correct cold-fill pressure. It is recommended that you put the pumps into manual operation to assist in purging the circuits. h. Disconnect the wires that are connected to the THERMOSTAT terminals of the customer connection board. Apply power to the boiler. The display will show the temperature of the water in the boiler. Press the v and ENTER keys simultaneously and hold for 1 second. The display will read:
The central heating pump will come on. If you then press the ^ key, the central heating pump will shut off. The display will read:

correct the external wiring. (This is a common problem when using 3-wire zone valves.) 5. Once the external thermostat circuit wiring is checked and corrected if necessary, reconnect the external thermostat circuit wires to the boiler low voltage terminal strip. Allow the boiler to cycle.
G. Condensate Removal 1. The boiler is a high efficiency condensing boiler. Therefore, the unit has a condensate drain. Condensate fluid is nothing more than water vapor, derived from combustion products, similar to that produced by an automobile when it is initially started. Condensation is slightly acidic (typically with a pH of 3 to 5) and must be piped with the correct materials. Never pipe the condensate using steel, copper, brass or other materials that will be subject to corrosion. Plastic PVC or CPVC pipe are the only approved materials. A condensate neutralizer, if required by local authorities, can be made up of lime crystals, marble or phosphate chips that will neutralize the condensate. This may be done by the installer or you may purchase a condensate neutralizer from HTP (7450P-212). 2. The boiler is equipped with a ¾ female socket weld fitting connection that must be piped to a local drain. It is very important that the condensate line is sloped downward away from the boiler to a suitable inside drain. If the condensate outlet on the appliance is lower than the drain, you must use a condensate removal pump, available from HTP (554200). This pump is equipped with two leads that can be connected to an alarm or another type of warning device to alert the user of a condensate overflow, which, if not corrected, could cause property damage. 3. If a long horizontal run is used, it may be necessary to create a vent in the horizontal run to prevent a vacuum lock in the condensate line. 4. Do not expose the condensate to freezing temperatures. 5. It is very important you support the condensation line to assure proper drainage.

If the boiler is set up as a cascade master and you then press the ^ key again, the DHW pump will shut off, the system pump will come on, and the display will read:

H. Final Checks Before Starting Boiler 1. Read Startup Procedures within this manual for proper steps to start boiler. (See Startup Report to record steps for future reference.) 2. Verify the boiler and system are full of water and all system components are correctly set for operation.

NOTE: The boiler must be programmed as a cascade master for the Service Pump SH screen to display. Use the ^ and v keys to toggle between running each pump in the system as required to help bleed out all entrapped air. Some good indicators that air is removed include the absence of gurgling noises in the pipes and pump operation becoming very quiet. Pressing ^ and v together at any time will return the boiler to normal operation. i. After the system has operated for five minutes, eliminate any residual air by using the manual air vents located throughout the system. j. If purge valves are not installed in the system, open manual air vents in the system one at a time, beginning with the lowest floor. Close vent when water squirts out. Repeat with remaining vents. k. Refill to correct pressure.
F. Check Thermostat Circuit(s) 1. Disconnect the two external wires connected to the boiler thermostat terminals (low voltage terminal strip). 2. Connect a voltmeter across these two incoming wires with power supplied to the thermostat circuits. Close each thermostat, zone valve and relay in the external circuit one at a time and check the voltmeter reading across the incoming wires. 3. There should NEVER be a voltage reading. 4. If a voltage reading does occur under any condition, check and

Ensure the boiler is full of water before firing the burner. Failure to do so will damage the boiler. Such damage IS NOT covered by warranty, and could result in property damage, severe personal injury, or death.
3. Fill condensate trap with water. 4. Verify electrical connections are correct and securely attached. 5. Inspect exhaust vent and intake piping for signs of deterioration from corrosion, physical damage or sagging. Verify exhaust vent and intake piping are intact and correctly installed per Venting Section and local codes.
I. Setting Up a Single Boiler When power is applied to the boiler, the control first completes a power-up systems check. During this time the combustion fan may run. The display will initially show the current boiler supply temperature. If a fault is detected during the power-up test, the control will display the appropriate fault code. Otherwise, the display will continue to show the boiler supply temperature and stand-by, waiting for a demand for heat. When a demand for heat is received, the control begins the following demand sequence. The boiler first turns on the pump. The control will measure the supply temperature. If it is below the set point temperature minus the ignition differential the control will ignite the burner.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

After the burner is lit, the control modulates the firing rate to control the supply water temperature and meet the heat demand. When the thermostat or indirect water heater temperature is met, the control will extinguish the burner and run the combustion fan to purge gasses from the combustion chamber. In addition, the pump will run for a pump post purge interval. The control will then be in standby, waiting to process the next demand for heat. During this process, the control will extinguish the burner if it senses a dangerous or unsafe condition. If the control determines that a dangerous or unsafe condition has occurred, the control may lock out the boiler and prevent it from igniting until a maintenance person diagnoses the problem, repairs it, and resets the control. In the event that the control goes into lockout, it will show a diagnostic code on the display, illuminate the LED fault indicator, and close the alarm relay contacts to aid in recognition of the condition, diagnosis, and repair.
J. Setting Up a Cascaded System If the boiler is part of a cascaded system the operation is somewhat different. The control of each boiler in a cascaded system completes its own power up system check. One of the boilers in the cascade system is designated as the master boiler. After the master boiler completes its power up sequence, it checks the communication bus to see if any other boilers are present. If other boilers are present, the master control determines these follower boiler addresses. The master boiler control will recheck the bus every few seconds as long as it is powered up to update the status of the connected boilers. The control in the master boiler processes all heat demands and dictates which of the follower boilers should light and what firing rate the followers should try to achieve. When the master boiler receives a demand for heat, it determines which boiler is first in the firing sequence and sends that boiler a command to begin a demand sequence. That boiler will then begin a demand sequence as described above. Once the boiler ignites, the master boiler control will increase the firing rate command to that boiler until the system sensor temperature is at the set point temperature plus the differential, or that boiler is at high firing rate. If the command from the master boiler control gets to the high firing rate of the follower boiler, but the system sensor is below the required temperature, the master boiler control will then tell the next boiler in the firing sequence to begin its demand sequence. The master boiler control will then begin to ramp up the firing rate command of that boiler. This process will continue while there is a demand until all boilers in the cascade system are at high fire or the desired temperature of the system sensor is reached. If the system sensor temperature reaches tank set point and differential before all boilers are at high fire, the master control will modulate the cascade command signal to maintain the system sensor at set point and differential until the demand is complete. When the system sensor is equal to the set point temperature, demand is complete, and the master boiler control will extinguish all boilers that may be lit. If the demand decreases, the firing rate command and amount of boilers lit will decrease exactly opposite as described above. Whenever the master boiler control needs to fire a follower boiler, it sends a firing rate command to that boiler. The follower boiler will respond to the command until its supply sensor temperature gets to be 5oF above the set point temperature plus the differential, at which point the individual boiler will modulate on its own so as not to overheat. As a result, it is not uncommon to see the cascade output at maximum but individual boilers firing at less than their maximum firing rate.

extinguish the burner and, if necessary, go to a lockout condition. In this way, every boiler in the system has its individual safety controls intact and operational, even if the firing of the boiler is under control of the master boiler. In the event that the system sensor fails, all boilers in the system will ignite simultaneously when there is a demand, and each boiler will individually regulate firing rates to maintain the master set point temperature (supply temperature set point + differential) at the individual supply sensors built into the boiler. If this should happen, the master boiler will display an E03 fault code, indicating that the supply sensor has failed.
L. Cascade System Programming 1. If the boiler is used alone, skip this section. 2. Programming the Master Boiler:
a. Make sure there is no demand for heat being supplied to the boiler. b. Apply power to the boiler. c. Enter the system setting program navigation following instructions in this manual. d. Verify that cascade address function 15 is set to 0. This makes the master boiler address 0. NOTE: The Master Boiler MUST be addressed as 0. e. Change CASCADE MODE Function 23 to 928 BOILERS. f. Exit the installer menu. 3. Programming Follower Boilers: NOTE: READ THE NOTES BELOW BEFORE PROGRAMMING
FOLLOWER BOILERS · The master boiler will share its alarm output with the boiler
addressed as 1. · If one of the follower boilers has an indirect fired water heater
connected to it, the address of this boiler must be 2 or greater. · It is recommended but not necessary to address boilers in the
order that they are wired. · No two boilers can have the same address. · It is not required to use all consecutive address numbers.
Example: In a 2 boiler system with an indirect connected to the follower, the follower address would be 2 (address 1 is not used). · Maximum amount of boilers in a cascaded system is eight (8). a. Make sure there is no demand for heat being supplied to the master boiler. b. Apply power to the follower boiler you are working on. c. Enter system settings following instructions in this manual. d. Set cascade address parameter 15 to 1 for the first follower, 2 for the second follower, etc. depending on which boiler you are programming based on the above notes. This establishes the boiler as a follower in a cascaded system and enables data to be transferred as needed for the system to function at full capability. e. Change CASCADE MODE Function 23 to 928 BOILERS. f. Exit the installer menu.

K. Lockout Condition If any boilers, including the master boiler in the cascade system, are in a lockout condition, the master control will recognize the lockout condition and skip over the boiler in the firing sequence. Each boiler in the cascade system is responsible for its own safety functions. So, if any individual boiler control senses an unsafe condition, it will

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 10 - Start-Up Procedure
FOR YOUR OWN SAFETY READ BEFORE OPERATING 1. This boiler does not have a pilot. It is equipped with an ignition device which automatically lights the burner. Do not try to light the burner by hand. 2. BEFORE OPERATING: Smell all around the boiler area for gas. Be sure to smell next to the floor because some gas is heavier than air and will settle on the floor.
3. WHAT TO DO IF YOU SMELL GAS · Do not try to light any boiler. · Do not touch any electric switch, do not use any phone in your
building. · Immediately call your gas supplier from a neighbor's phone.
Follow the gas suppliers' instructions. · If you cannot reach your gas supplier, call the fire department. · Turn off the gas shutoff valve (located outside the boiler) so
that the handle is crosswise to the gas pipe. If the handle will not turn by hand, don't try to force or repair it, call a qualified service technician. Force or attempted repair may result in a fire or explosion. 4. Do not use this boiler if any part has been under water. Immediately call a qualified service technician to inspect the boiler and to replace any part of the control system and any gas control that has been damaged. 5. The boiler shall be installed so the gas ignition system components are protected from water (dripping, spraying, rain, etc.) during boiler operation and service (circulator replacement, condensate trap, control replacement, etc.) Failure to follow these instructions could result in property damage,
serious personal injury, or death.
If you discover any evidence of a gas leak, shut down the boiler at once. Find the leak source with a bubble test and repair immediately. Do not start the boiler again until the leak is repaired. Failure to comply could result in substantial property damage, severe personal injury, or death.
A. Control Overview The control is one of the primary safety devices of the boiler. It monitors the safety sensors of the boiler to assure safe and efficient operation. The control has many features associated with system design. This section addresses programming features, including Boiler Settings / System Settings / Maintenance Settings and System Diagnostics, to help in customizing your control. It is important to fully understand control capabilities before customization, as its factory defaults may already fit your system design and not require any adjustment at all.
B. Navigation of the Display The display includes a two line backlit LCD readout to provide informative messages about the operation of the boiler. Many operating parameters can be viewed and adjusted by using the six buttons on the display. The function of each button is described below. RESET The RESET button has two functions.
Resets any lockout error code Returns the user to the default display screen. ENTER The ENTER key is used to access parameter programming mode. To access this mode, hold down the ENTER key for more than 4 seconds. The readout will change to:
ENTER MENU CODE 000
One of the zeroes will be blinking. Use the ^ v arrow keys to change the blinking digit to the correct value. Use the < > arrow keys to select the next digit to change and again use the ^ v keys to change the value. Repeat until the correct code is entered. Press the ENTER key

to accept the code entered. If the code is correct, the readout will change to the appropriate screen. If the programming code is not accepted, the readout will continue to display as shown above. ENTER is also used to enable a function for editing. After the user navigates to the desired function, the user holds down ENTER for one second. When ENTER is released, the function value will begin to blink. The function can now be changed using the ^ v keys. After the new value is displayed, the user then presses ENTER for 1 second to lock the new value of the function. The value will then stop blinking. LEFT AND RIGHT ARROW KEYS < > are used to navigate between the default display, status display, analog and cascade displays if they are enabled. The < > keys are also used in programming modes to change between programmable functions. It is recommended you use the Menu Maps in the back of this manual and the detailed menu instructions printed in this section to help in menu navigation. UP AND DOWN ARROW KEYS ^ v are used to navigate between the various functions displayed in the menu. After the function is enabled for editing by pushing the ENTER key, the ^ v keys are used to adjust the function upward or downward to the desired value.
C. Operating Instructions Before operating the unit, it is important to remove the cover and verify that the gas line and water lines are connected to boiler and fully purged. If you smell gas, STOP; Follow the safety instructions listed in the first part of this section. If you do not smell gas, follow the next steps. 1. Turn down the thermostats before applying power to the boiler. If 010 volt or other inputs are used, make sure that they are set so there is no call for heat while programming. 2. Turn on the power to the boiler or boilers if a cascade system used. 3. Next, check the boiler settings. Adjustment and factory defaults are outlined within this section. If a cascade system is used, it is important that all the boilers have the same boiler settings. 4. Next, check the system settings. Adjustments and factory defaults are outlined within this section. If a cascade system is used, it is important that the Master Boiler is programmed with the correct system settings. 5. Create a demand on the boiler or boilers if a cascade system is used. The user can monitor system functions when the boilers are operational. 6. If the boilers fail to start, refer to the troubleshooting section in the back of this manual.

D. Programming Boiler Settings Boiler Setting Program Access Note: Programming the boiler control is not possible when the boiler is firing. Make sure any input which can create a demand on the boiler, such as the tank thermostat, is turned off, so the boiler will remain idle to allow programming.

Screen

Description

ENTER MENU CODE 000

To access the boiler setting program, press and hold ENTER for 4 seconds until the display shows the screen at left.

ENTER MENU CODE 600

Use the arrow keys to log in the Boiler Menu Access Code - 600. Press ENTER to confirm the code and access the Boiler Setting Program navigation menu.

Table 19 - Boiler Setting Access

Boiler Setting Program Navigation Once the code is confirmed, the user can start to set the Boiler Settings. Use the arrow keys on the display to navigate through the Boiler Settings. A blinking setting indicates the setting can be

LP-550 Rev. 000 Rel. 022 Date 4.2.21

changed. To change a setting, press ENTER. Boiler settings can be increased by pressing ^ and decreased by pressing v on the display. When done, press ENTER. The setting will stop blinking and the user can move on to next setting. Press RESET to exit programming and store settings. Listed below are the boiler settings that can be programmed into the control.

Screen

Description

CENTRAL HEAT 180 oF

Allows the user to adjust the boiler set point from 50F to 190oF (Factory Default 180oF).

CENTRAL DIFF SET 30 oF

Adjusts the boiler differential set point from 5oF to 30oF (Factory Default 30oF).

DHW SETPOINT 119 oF

Adjusts the indirect tank set point from 70oF to 185oF (Factory Default 119oF).

DHW DIFF SETPOINT 7 oF

Adjusts the DHW differential set point from 1oF to 30oF (Factory Default 7oF).

TEMP DISPLAY C OR F oF

Adjusts

the

temperature

measurement in F = Fahrenheit to C

= Celsius (Default is Fahrenheit).

Table 20 - Boiler Setting Program Navigation

Clock Settings (NOTE: The clock will reset if the boiler is powered off for more than a week.)

Screen

Description

CLOCK MODE 08/28/2009

(12/24) Fr 9:42A

Changes the clock from 12 hour mode (8:45 PM) to 24 hour mode (20:45). To change to 24 hour mode, press ENTER. The letter (A or P) after the time will blink. Press the up or down arrow key once and the letter will disappear. Press ENTER to save the new setting.

CLOCK HOUR

Allows the user to adjust the hour

08/28/2009 Fr 10:01A setting.

CLOCK MINUTE 08/28/2009 Fr 10:01A

Adjusts the minute setting.

CLOCK DAY OF WEEK 08/28/2009 Fr 10:01A

Adjusts the day of the week.

CLOCK DATE MODE 08/28/2009 Fr 10:01A

Allows the user to switch to European date format (2009/08/28) from US format (08/28/2009).

CLOCK YEAR 08/28/2009

Fr 10:01A Adjusts the year setting.

CLOCK MONTH 08/28/2009 Fr 10:01A

Adjusts the month setting.

CLOCK DATE 08/28/2009

Fr 10:01A The clock is set.

Table 21 - Clock Setting Screens

NOTE: The internal clock does not adjust for daylight savings time

and requires manual adjustment.

E. Programming the System Setting System Setting Program Access Note: Programming the boiler control is not possible when the boiler is firing. Make sure any input which can create a demand on the boiler, such as the tank thermostat, is turned off, so the boiler will remain idle to allow programming.

Screen

Description

ENTER MENU CODE 000

To access the boiler setting program, press and hold ENTER for 4 seconds until the display shows the screen at left.

Use the arrow keys to log in the

ENTER MENU CODE 925

Boiler Menu Access Code - 925. Press ENTER to confirm the code and access the System Setting

Program navigation menu.

Table 22 - System Setting Access

F. System Setting Program Navigation Once the System Menu Access Code is confirmed, the user can begin to set the system setting menu. Use the < > keys on the display to navigate through the System Settings. To change a setting, press ENTER. System settings can be increased by pressing ^ and decreased by pressing v on the display. When done, press ENTER. The setting will stop blinking and you can move on to next setting. Press RESET to exit programming and store settings. Listed below are the boiler settings that can be programmed into the control.

Screen Function 1

Description Factory Program Mode

MODE INDIRECT

This indicates that the control is

configured correctly. Do not change this setting.

Function 3

DHW Tank Max Temp

DHW TANK MAX TEMP

180 oF

This is the maximum temperature that can be selected in boiler settings for the DHW tank. Factory Default is 180oF. (Range: 95oF to 180oF)

Function 6

DHW Post Pump Time

DHW POST PUMP TIME

0 MINUTES

The indirect pump has the ability to post purge energy from the boiler to run the pump after the set point has been achieved. Please note that running the pump for a time greater than 5 minutes may cause tank energy to be released back to the heat exchanger. Factory Default of 0 Minutes. (Range: 0 10 minutes)

Function 7

Warm Weather Shutoff

When used with an outdoor sensor,

WARM WEATHER OFF 68 oF

warm weather shut down will disable the boiler if the programmed outdoor temperature is exceeded. Default:

68oF (Range: 41oF to 122oF).

Function 8

Min Outdoor Temp

MIN OUTDOOR TEMP

5 oF

Function 9

MAX SUPPLY TEMP

180 oF

Sets the minimum outdoor design temperature for the system. Default: 5oF (Range: -49oF to 32oF).
Max Supply Temp
Sets the maximum design supply temperature based on the minimum outdoor design temperature. Default: 180oF (Range: 77oF to 190oF).

Function 10

Max Outdoor Temp

MAX OUTDOOR TEMP

68 oF

Sets the maximum outdoor design
temperature for the system design. Default: 68oF (Range 32oF to 190oF).

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Screen

Description

Function 11

Min Supply Temp

MIN SUPPLY TEMP 95 oF

Sets the design supply water temperature based on the maximum 11 outdoor design temperature. Default: 95oF (Range: 32oF to 190oF).

Function 12

Min Boiler Temp

MIN BOILER TEMP 68 oF

Sets the design minimum heat curve

temperature for central heat. Default: 68oF (Range: 32oF to 190oF).

Function 13

CH Post Pump Time

CH POST PUMP TIME

0 MINUTES

Allows the user to set the boiler pump post purge time once the thermostat is satisfied. Default: 0 minutes (Range: 0 10 minutes).

Function 14

DHW Priority

DHW PRIORITY 30 MINUTES

Allows the user to set the maximum

run time for the indirect fired water

heater and the minimum run time for central heating. Default: 30 minutes

(Range: 0 60 minutes).

Function 15

Cascade Address

CASCADE ADDRESS 0

Bus addressing boilers (maximum boilers allowed is eight (8) in a cascade system). Master Boiler address is 0 and 15 Follower Boilers are addressed 1 thru 7. Default: 0 (Range: 0 15). NOTE: DO NOT USE ADDRESSES 8 - 15.

Function 16

Optional Inputs

OPTIONAL INPUT OFF

Allows the user to select optional inputs to control or monitor the 16 system. Default: OFF (Range: Off / Booster Board / 0-10 Volt).

Function 17

0-10 Volt Function

0-10 VOLT FUNCTION

TEMPERATURE

Controls boiler modulation through temperature control. Factory Default = Temperature (Range: Temperature or Fan Speed).

Function 18

Step Modulation Mode

STEP MODULATE MODE

Allows the user to turn ON step modulation, which regulates burner output in six steps at one minute intervals. Step modulation will start at the last modulation rate of the boiler and work up one minute at a time. Default: ON (Selection: OFF or ON).

Function 19

Boiler DHW Temp

BOILER SUPPLY DHW

180 oF

Allows the user to program the boiler
supply water temperature to the
indirect heat exchanger during a demand cycle. Default: 180oF (Range: 119oF to 190oF).

Function 20

Water Safety Input

The user can select various water

WATER SAFETY INPUT safety inputs used in the boiler system.

WATER PRESSURE

20 Default: Water Pressure (Range: NONE

/ Flow Switch / Water Pressure).

Function 21

Error Outdoor Sensor

ERROR OUTD SENSOR

OFF

Allows the user to set the control to display an error message if an outdoor sensor is open or shorted. NOTE: This error does not stop the boiler from running. Factory Default: OFF (Range: ON / OFF / PHOEN ON).

Function 22

Adjust Boiler Output %

ADJ BOILER OUTPUT 100%

Adjusts the boiler output down from 100% to 50%. Factory Default: 100%. (Range: 100% 50%)

Function 23

Cascade Mode

CASCADE MODE OFF

Allows the user to select cascade

mode. Select OFF if boiler is operating

alone. Select 928 BOILRS to establish a

cascaded system. Factory Default: OFF (Range: OFF / 928 BOILRS).

NOTE: Select OFF if boiler is operating

alone or with Vision 3 panel.

Function 24

Cascade Rotation

CASCADE ROTATION 48 HOURS

Sets the amount of hours before the first boiler in the cascade firing rotation will be changed. NOTE: If this is set to 24 0, the firing order of the boilers will not rotate. Default: 48 hours (Range: 0 240 hours).

Function 25

Cascade DHW Mode

DHW CASCADE MODE ENTIRE CASCADE 25

NOTE: "SYS PMP OFF W/DHW" has been added to Function 25. This new setting only applies to a single boiler cascade. Depending on system piping, this option allows you to run both the CH and DHW pumps during a DHW call, but the SYS pump will NOT be energized during the DHW call. ENTIRE CASCADE (Range: ENTIRE CASCADE / DHW ON LOOP / ONLY MASTER / SYS PMP OFF W/DHW).

Function 26

System Freeze Protection

SYS FREEZE PROT PROTECT OFF

NOTE: This parameter is only present

if the boiler is a cascade master. Allows

the user to set the freeze protection

when a system pump is used. Factory Default: OFF. Selection of temperature

activates freeze protection. (Range:

OFF, -40oF 104oF).

Function 27

Error System Sensor

ERROR SYSTEM SENS

Sets the control to display an error message if the system sensor is open or shorted. NOTE: This error does not stop the boiler (or boilers) from running. Factory Default: ON (Range: ON / OFF).

Function 28

Freeze Protection

FREEZE PROTECTION ON

Allows the user to set freeze protection on the boiler. Factory Default: ON (Range: ON / OFF).

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Screen

Description

Function 54

Boost Time

Function 29

DHW MODULATE MODE

NORMAL MOD

Function 30

EXTRA BOILER MODE

OFF

Function 31

SYSTEM SENSOR MODE

OFF

Function 32

SERVICE SCHEDULE

OFF

Function 37

MODBUS MODE

OFF

DHW Modulation Mode
This parameter controls how the boiler modulates for a DHW demand. In NORMAL MOD mode, the boiler will modulate down from high fire when there is a DHW demand. In LOW MOD mode, the boiler will modulate up from low fire when there is a DHW demand. This mode is useful to minimize short cycling when a large boiler and small indirect tank are used together. Factory Default: NORMAL MOD (Range: NORMAL MOD / LOW MOD).
Extra Boiler Mode
Allows for a non HTP boiler to be controlled when the cascade output has risen above the percent of the cascade firing rate set in this parameter. Factory Default: OFF (Range: 50% - 100%).
System Sensor Mode
Suppresses the `NO FOLLOWER' display message if the boiler is used as a cascade master boiler with no follower boilers connected. Factory Default: OFF (Range: ON / OFF).
Service Schedule
Selects a service date or time based on the boiler run hours to program the boiler maintenance schedule. Factory Default: OFF (Range: Date or Run Hours). NOTE: Without setting this function, Functions 33/34/35/36 will not display.
Modbus Mode
Enables Modbus Mode on the appliance. Factory Default: OFF (Range: OFF, ON, AUTO). NOTE: Turning Modbus Mode "ON" will open a number of additional parameters to customize Modbus installation. See Modbus Instructions (lp-372) for details. NOTE: Turning this Mode "ON" without a connected and powered Modbus communication adapter (p/n 7350P-629) will result in improper appliance operation. Service calls associated with this ARE NOT covered by warranty.

BOOST TIME 0

Temporarily overrides the Outdoor

Reset Curve to bring the boiler up to

the maximum setpoint to satisfy a

thermostat call in less time. Factory

Default: 0 min (Range: 0-762 min in

increments of 6 minutes.) EXAMPLE:

If 6 minutes is selected, and there has

been a call for heat for 6 minutes, the boiler will override the Outdoor Reset

Curve and boost to the maximum

setpoint until the call for heat is

satisfied. The boiler will then continue

to boost for 6 additional minutes

before returning to the Outdoor Reset

Curve.

Function 55

CH Pump Priority

PUMP CH PRIO OFF

NOTE: This function applies only to

boilers with a Cascade Address of 0.

Controls whether the CH pump will

meet a call for heat while also meeting

or answering a DHW call. A setting

of OFF will not run the CH pump while running the DHW pump; an ON

setting will run the CH pump while

simultaneously running the DHW

pump. Factory Default: OFF (Range

OFF/ON)

Function 56

OA1 Configuration

O-10V A OUTPUT CONFIG

POWER BOIL

Controls the operation of the 0-10V A output on the Field Connection Board. Factory Default: BOIL POWER (Range: BOIL POWER / CASC POWER / FAN SPEED / ALARM / TEMPERATUR / FLAME / PUMP dT).

The following information details the 0-10V output parameters described in Function 56 that can be read at a Building Management System. BOIL POWER - 0-10V output is proportional to boiler firing rate. 0V = Not Firing, 1.5V = Minimum Firing Rate, 10V = Maximum Firing Rate CASC POWER - When configured on the Cascade Master, 0-10V is proportional to the firing rate of the Cascaded System. 0V = Not Firing, 1.5V = Minimum Firing Rate (One Boiler Lit), 10V = Maximum Firing Rate of all Connected Boilers FAN SPEED - Output is proportional to boiler fan speed. 0V = Fan is Off, 1.5V = Minimum Fan Speed, 10V = Maximum Fan Speed ALARM - 0V = Alarm is Off, 10V = Alarm is On TEMPERATUR - Output follows boiler temperature setting based on outdoor reset. 0V = Minimum Boiler Temperature for Maximum Outdoor Temperature Setting. 10V = CH (or cascade) temperature setting. This number will vary with the outdoor temperature so that the user can know what setpoint temperature the boiler is trying to achieve. FLAME - Equals boiler Flame Current. 0V = 0ua, 10V = 10ua. PUMP dT - This output controls pump speed to maintain the desired Delta T. 0V = OFF, 2V (or output offset value greater than 2) = Minimum Pump Speed, 10V = Maximum Pump Speed.

Function 57

OA1 Offset

O-10V A OUTPUT OFFSET

1.5

This value is added to the OFFSTATE VOLT OA1 value, to determine the total voltage output required at the minimum case. Factory Default: 1.5 (Range: 0.0 to 9.9)

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Screen

Description

Hours

Function 58

O-10V B OUTPUT CONFIG

POWER BOIL

Function 59

OA2 Configuration
Controls the operation of the 0-10V B output on the Field Connection Board. Factory Default: BOIL POWER (Range: BOIL POWER / CASC POWER / FAN SPEED / ALARM / TEMPERATUR / FLAME).
OA2 Offset

SERVICE SCHEDULE 10000's 000000

Sets the two right digits of the amount

of run hours for the next service reminder.

Function 36

Telephone

TELEPHONE # 000 000 0000

Allows the user to input a telephone

number that will display maintenance is required.

when

Table 24 - Maintenance Reminder Function Screens

O-10V B OUTPUT OFFSET

1.5

Function 60

CH dT SETTING

20F

This value is added to the OFFSTATE VOLT OA2 value, to determine the total voltage output required at the minimum case. Factory Default: 1.5 (Range: 0.0 to 9.9)
CH dT Setting
This parameter is only available when PUMP dT is selected in Function 56. Determines the desired temperature difference between the SUPPLY And RETURN temperatures. Factory Default: 20F (Range: 0 - 47F)

G. Resetting the Maintenance Schedule When the system control flashes MAINTENANCE REQUIRED, it is advisable that you call for service. After the service is performed, reset the schedule for the next required service by using the following steps. Press ENTER on the display for 3 seconds. The Menu code will appear as 000. This does not change. Press ENTER again. SERVICE SCHEDULE RESET will be displayed. Using the > key scroll to the selection of year or hours. Press ENTER to reset the selected Service Schedule. To change a setting, press ENTER. Press the ^ and v keys to make adjustments. Press ENTER when reset is complete.

Function 61

Offstate Voltage OA1

This parameter is only available when

PUMP dT is selected in Function 56.

OFFSTATE VOLT 0-10V A Determines the voltage present in

0.0V

61 OA1 when the pump is supposed to

be OFF. Factory Default: 0.0 (Range:

0.0 to 9.9)

Table 23 - System Setting Program Navigation

NOTE: For the following functions, you must have your maintenance

function turned on.

To change these functions, press ENTER. The left most digit will begin

to blink. Use the ^ or v arrows to change the digit. Use the < > arrow

keys to switch between digits. When you've made your selection, press

ENTER again.

Screen Function 33 SERVICE SCHEDULE YEAR 00/00/2000
SERVICE SCHEDULE 10000's 000000
Function 34

Description

Year

Allows the user to set the year of the 33 next service reminder.

Hours

Allows the user to set the left two

digits of the amount of run hours before next service reminder.

Month

If the date function was selected, this

SERVICE SCHEDULE

function programs the month. If you

MONTH

00/00/2000 selected the run hour function, you

will need to program 10,000 hours, if

required.

Hours

SERVICE SCHEDULE 10000's 000000

Allows the user to set the middle two

digits of the amount of run hours before next service reminder.

Function 35

Day

SERVICE SCHEDULE DAY 00/00/2000

35 Sets the day of next service reminder.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 11 - Start-Up Procedures for the Installer

CENTRAL HEATING CURVE Factory Default
212

203
201°
194

185

176

FUNCTION 9

167

158 DEFAULT RESET CURVE
149

SUPPLY OUTLET TEMPERATURE (F) FUNCTION 8 FUNCTION 10

131

122

113

104

95 FUNCTION 11
86

32
-59 -41

-24

-9

5°
OUTSIDE TEMPERATURE (F)

81 99

68°

CENTRAL HEATING CURVE
Plot your Curve
212

203

194

185

176

167

158

SUPPLY OUTLET TEMPERATURE (F)

149

131

122

113

104

-59

-41

-24

-9

81 99

OUTSIDE TEMPERATURE (F)

Table 25 - Heating Curve - NOTE: The user can adjust the heat curve down by lowering the central heating temperature.

A. Boiler Control Status Menu The boiler control also has the ability to review system status. To access the status screens, press >. Once the first value is displayed, press ^ and v to scroll through additional information. At any point press RESET to exit the status screens.

Screen

Description

SUPPLY RETURN

180oF 150oF

This is the first screen that appears after pressing >, and shows the actual temperatures measured by the supply and return sensors. NOTE: If the boiler is configured to use a 0 10 volt input, the return sensor is disabled and the second line of the display will be blank.

Press v once.

CH SET BURNER

180oF 120oF

The screen displays the current central heating temperature set point on the top line. NOTE: This temperature set point may vary from what was set in the boiler settings if an outdoor sensor is used. The actual temperature measured by the burner sensor is displayed on the bottom line.

Press v once.

CH DEMAND BOILER

OFF This screen displays the central heat demand set for the cascade system.

Press v once.

This screen appears only when the boiler is set as a Master Boiler.

CAS SET SYSTEM

180oF 112oF

This screen displays the cascade set point (maximum 190oF) on the top line. The system sensor reading is on the second line. The control will cascade the boilers up to this set point depending on demand.

Press v once.

DHW SET DHW

119oF 117oF

Displays the current tank temperature set point on the top line. The actual temperature measured by the tank or return sensor (HTP 7250P-325) is displayed on the bottom line. If a mechanical aquastat is used in place of the recommended sensor, the second line will display `OFF' in place of the temperature if the aquastat measures close to its set temperature, or `ON' if the aquastat temperature is too low.

Press v once.

OUTDOOR FLUE

The current outdoor temperature

is displayed on the top line. If there

is no outdoor sensor connected

11oF 95oF

to the boiler, this line will display "OFF" in place of the temperature. If the outdoor sensor is shorted, this

line will display "ON" in place of the

temperature. The second line displays

the current boiler flue temperature.

Press v once.

FLAME FAN SPEED

0.0uA 3497 RPM

This screen displays boiler flame current on the top line. The second line displays boiler fan speed.

Press v once.

0-10 V BOILER

The top line displays the voltage on 0.0V the optional input. This voltage is only
relevant if an external 0-10 volt signal is being used to control the boiler.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Press v once.

BUS COMM

This display shows the status of the communication bus between multiple boilers. If in a single boiler configuration, the display will show NO CONN `NO CONN'. In a multiple boiler configuration, if this is the Master Boiler and other boilers are connected to the communication bus and powered, this screen will show the address of each boiler connected to the bus.

Press v once.

POWER ON CH ON

The top line indicates the amount of

0H 0H

hours the boiler has been powered over its life. The second line indicates how many hours the burner has been

on for central heat demand over its life.

Press v once.

DHW ON GOOD IGNIT

The top line indicates the hours the burner has been on for hot water 0H demand over the boiler's life. The 1X second line indicates how many times the burner has successfully ignited over the boiler's life.

Press v once.

This screen appears only when the boiler is set as a Master Boiler.

SYS CH ON SYS DHW ON

0H 0H

This screen displays how many hours the boiler has run to meet central heat and DHW demand.

FAULT HISTORY 08/28/2009
Press v once.
FAULT HISTORY 08/28/2009
Press v once.
FAULT HISTORY 08/28/2009
Press v once.
FAULT HISTORY 08/28/2009
Press v once.

3 Fr 5:19A

The third oldest boiler control lockout fault. The top line will alternate between the words `FAULT HISTORY' and the actual fault encountered. The bottom line will display the date and time that the fault occurred.

4 Fr 5:19A

The fourth oldest boiler control lockout fault. The top line will alternate between the words `FAULT HISTORY' and the actual fault encountered. The bottom line will display the date and time that the fault occurred.

5 Fr 5:19A

The fifth oldest boiler control lockout fault. The top line will alternate between the words `FAULT HISTORY' and the actual fault encountered. The bottom line will display the date and time that the fault occurred.

6 Fr 5:19A

The sixth oldest boiler control lockout fault. The top line will alternate between the words `FAULT HISTORY' and the actual fault encountered. The bottom line will display the date and time that the fault occurred.

Press > once at any status screen.

TEMPERATURE CONTROL Displays 0-10V status when 0-10V is

ANALOG SIG 0.2 V

connected.

Table 26 - Boiler Control Status Menu Screens

The next ten screens display the last ten boiler lockout faults. Press v to scroll through the faults from most recent to oldest.

Screen

Description

FAULT HISTORY 07/27/2009 5:19A

This screen displays the most recent boiler control lockout fault. The 1 top line will alternate between the Mo words `FAULT HISTORY' and the fault code encountered. The bottom line displays the date and time the fault occurred.

Press v once.

FAULT HISTORY 08/28/2009

The second oldest boiler control

lockout fault. The top line will

2 Fr 5:19A

alternate between the words `FAULT HISTORY' and the actual fault encountered. The bottom line will

display the date and time that the

fault occurred.

Press v once.

FAULT HISTORY 08/28/2009
Press v once.
FAULT HISTORY 08/28/2009
Press v once.
FAULT HISTORY 08/28/2009
Press v once.

7 Fr 5:19A
8 Fr 5:19A
9 Fr 5:19A

FAULT HISTORY

08/28/2009

Fr 5:19A

Table 27 - Boiler Fault Screens

The seventh oldest boiler control lockout fault. The top line will alternate between the words `FAULT HISTORY' and the actual fault encountered. The bottom line will display the date and time that the fault occurred.
The eighth oldest boiler control lockout fault. The top line will alternate between the words `FAULT HISTORY' and the actual fault encountered. The bottom line will display the date and time that the fault occurred.
The ninth oldest boiler control lockout fault. The top line will alternate between the words `FAULT HISTORY' and the actual fault encountered. The bottom line will display the date and time that the fault occurred.
The tenth oldest boiler control lockout fault. The top line will alternate between the words `FAULT HISTORY' and the actual fault encountered. The bottom line will display the date and time that the fault occurred.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Screen

Description

This screen displays the most recent

BLOCKING HISTORY 1

08/28/2009

Fr 5:19A

boiler control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the

blocking code encountered.

Press v once.

Displays the second oldest boiler

BLOCKING HISTORY 2

08/28/2009

Fr 5:19A

control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the actual

blocking code encountered.

Press v once.

Displays the third oldest boiler

BLOCKING HISTORY 3

08/28/2009

Fr 5:19A

control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the actual

blocking code encountered.

Press v once.

Displays the fourth oldest boiler

BLOCKING HISTORY 4

08/28/2009

Fr 5:19A

control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the actual

blocking code encountered.

Press v once.

Displays the fifth oldest boiler

BLOCKING HISTORY 5

08/28/2009

Fr 5:19A

control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the actual

blocking code encountered.

Press v once.

Displays the sixth oldest boiler

BLOCKING HISTORY 6

08/28/2009

Fr 5:19A

control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the actual

blocking code encountered.

Press v once.

Displays the seventh oldest boiler

BLOCKING HISTORY 7

08/28/2009

Fr 5:19A

control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the actual

blocking code encountered.

Press v once.

Displays the eighth oldest boiler

BLOCKING HISTORY 8

08/28/2009

Fr 5:19A

control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the actual

blocking code encountered.

Press v once.

Displays the ninth oldest boiler

BLOCKING HISTORY 9

08/28/2009

Fr 5:19A

control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the actual

blocking code encountered.

Press v once.

Displays the tenth oldest boiler

BLOCKING HISTORY 10

08/28/2009

Fr 5:19A

control blocking error. The top line will alternate between the words `BLOCKING HISTORY' and the

blocking code encountered.

Press v once.

OA1

0.0V Displays the voltage level present

OA2

0.0V on the 0-10VA and 0-10VB inputs.

Press v once.

ARBA-P ASBA-P

160831 150806

Displays the Comfort and Safety firmware revisions programmed into the control.

Table 28 - Boiler Blocking Screens

B. Cascade Menu This menu is accessed by pressing < at the default menu or > at the
status menu.

Screen CASCADE MASTER READY SYS PUMP OFF
CASCADE NO FOLLOWER SYS PUMP OFF
CASCADE NO SENSOR SYS PUMP OFF

Description
This screen displays when the boiler is configured as a Cascade Master and the system is ready to accept a demand for heat. The second line indicates the cascade system pump output status. This screen alternates with the default screen every 5 seconds or can be accessed by pressing the < key from the default screen.
This screen displays when the boiler is configured as a Master Boiler and there are no connected follower boilers, or the follower boilers are not powered. The second line indicates cascade system pump output status. This screen alternates with the default screen every 5 seconds or can be accessed by pressing the < key from the default screen.
This screen displays when the boiler is configured as a Master Boiler and there is no system temperature sensor connected or the system sensor is defective. The cascade system will still function in this situation with reduced efficiency. All boilers will run simultaneously rather than in a staged fashion. The second line indicates cascade system pump output status. This screen will alternate with the default screen every 5 seconds or can be accessed by pressing the < key from the default screen.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Screen

Description

This screen displays information about

cascade status. The TT in the center

of the top line shows that cascade

demand is coming from TT contact

being closed. You may also see DHW

if the demand is from a DHW sensor,

or 0-10 if the demand is from a 0-10

volt input. The following numbers

CASCADE TT 0123 567 SYS PUMP ON 12:47P

show which boiler addresses are currently communicating to the master. If a boiler address is not used

or communicating, the number

will not display. In the example to

the left, boiler address #4 is not

communicating. When a boiler in the

system is firing, its address number will

alternate with a `.' to signify it is firing.

The bottom line shows the status of

the system pump output contacts.

Press v once.

This screen displays overall cascade

power output. The range of this value is

the number of boilers communicating

CASCADE PWR 100% PRESENT 01234567

with the Master x 100. For example, if 8 boilers are connected and firing, the maximum cascade power is 800%.

The second line shows which boiler

addresses are communicating with

the Master.

Press v once.

CASCADE SYST CASCADE SET

118oF 190oF

This screen displays current system temperature sensor reading on the top line and the cascade system temperature setting on the bottom.

Press v once.

BOILER 0 BOILER 1

100% 56%

This screen displays the current cascade power demand output on a per connected boiler basis for boilers addressed as 0 and 1. In the example, boiler 0 is being commanded to fire at 100% and boiler 1 at 56%. If this were a 2 boiler system, the `CASCADE PWR' screen above would read 156%.

Press v once.

BOILER 2 BOILER 3

This screen displays the current 0% cascade power demand output on a 0% per connected boiler basis for boilers
addressed as 2 and 3.

Press v once.

BOILER 4 BOILER 5

This screen displays the current 0% cascade power demand output on a 0% per connected boiler basis for boilers
addressed as 4 and 5.

Press v once.

BOILER 6 BOILER 7

This screen displays the current 0% cascade power demand output on a 0% per connected boiler basis for boilers
addressed as 6 and 7.

Press v once.

BOILER 8 BOILER 9

N/A N/A

This screen is not applicable.

Press v once.

BOILER A10 BOILER B11

N/A N/A

This screen is not applicable.

Press v once.

BOILER C12 BOILER D13

N/A N/A

This screen is not applicable.

Press v once.

BOILER E14 BOILER F15

N/A N/A

This screen is not applicable.

Table 31 - Cascade Menu

C. Boiler Test Mode This function is intended to simplify gas adjustment. The following tables include recommended combustion settings by fuel type and boiler fan speeds. Automatic modulation does not take place while the controller is in Test Mode. However, the boilers will modulate down if the program set point is reached while running in Test Mode. It is recommended to enter Test Mode with the largest load possible to create such a heat demand that Test Mode will not be interrupted. To enter Test Mode press ^ and ENTER simultaneously. NOTE: The boiler will automatically exit Test Mode after 20 minutes of operation. Press ^ to increase and v to decrease fan speed ten (10) RPM. Press ^ and ENTER simultaneously to go directly to max fan speed. Press v and ENTER simultaneously to go directly to min fan speed. To leave Test Mode press ^ and v simultaneously.

SERVICE RUN PUMP ON

3400 RPM 4:49P

Combustion Settings on All Models

Natural Gas (NG)

Propane (LP)

Fan Speed

Low Ignition High Low Ignition High

Carbon Monoxide 5-50 60-100 <150 5-50 60-100 (CO) PPM

<150

Carbon

Dioxide 8-10

8 1/2-10 1/2

(CO2) %

Table 29 - Combustion Settings - All Models

9-10 1/2 9 1/2-11

Model 80kBTU NG / LP
110kBTU NG 110kBTU LP 150kBTU NG 150kBTU LP 220kBTU NG 220kBTU LP 299 / 301kBTU NG 299 / 301kBTU LP 399kBTU NG 399kBTU LP Table 30 - Fan Speeds

Fan Speeds Ignition
3000 3800
3000

Min 1600 1500 1550 1600 1525 1320 1300 1420 1370 1500 1525

Max 5500 5150 5200
5550
5200 4800 5650 5800 6850 6625

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 12 - Troubleshooting

A. Boiler Error and Fault Codes If any of the sensors detect an abnormal condition, or an internal component fails during the operation of the boiler, the display may show an error message and error code. This message and code may be the result of a temporary condition, in which case the display will revert to its normal readout when the condition is corrected, or it may be a condition that the controller has evaluated as not safe to restart the boiler. In this case, the boiler control will be locked out, the red FAULT light will be lit, and the message "LOCKOUT" will be displayed on the readout in the lower line. The boiler will not start until a qualified technician has repaired the boiler and pressed the RESET button for more than 1 second. If there is an error message displayed on the readout, and the message "LOCKOUT" is not displayed and the FAULT light is not lit, then the message is the result of a temporary condition and will disappear when the problem corrects itself. IMPORTANT NOTE: If you see error messages on your display readout, call a technician immediately, since the message may indicate a more serious problem will occur soon.

Label all wires prior to disconnecting them when servicing the boiler. Wiring errors can cause improper and dangerous operation. Failure to follow these instructions may result in property damage or personal injury.
NOTE: If system return temperatures are maintained below the dew point, condensation will form on the inside of the boiler cabinet and cause some internal sheet metal components to rust.

B. Boiler Error The controller will display an error code and message when an error condition occurs. These error codes, descriptions, and recommended corrective actions are described in Section D.

C. Boiler Fault 1. The controller will illuminate the red "FAULT" indication light and display a fault code and message when a fault condition occurs. The alarm output will also activate. Most fault conditions cause the CH pump to run in an attempt to cool the boiler. 2. Note the displayed fault code and refer to Section D for an explanation of the message along with several suggestions for corrective actions. 3. Press RESET to clear the fault and resume operation. Be sure to observe the operation of the unit for a period of time to assure correct operation and no reoccurrence of fault message.

When servicing or replacing components that are in direct contact with boiler water, be certain that: · There is no pressure in the boiler. (Pull the release on the relief
valve. Do not depend on the pressure gauge reading. · The boiler water is not hot. · The electrical power is disconnected. · The gas is shut off. Failure to make these checks could result in substantial property damage, serious personal injury, or death.
DO NOT USE THIS APPLIANCE IF ANY PART HAS BEEN SUBMERGED IN WATER. Immediately call a qualified service technician. The appliance MUST BE replaced if it has been submerged. Attempting to operate an appliance that has been submerged could create numerous harmful conditions, such as a potential gas leakage causing a fire and/or explosion, or the release of mold, bacteria, or other harmful particulates into the air. Operating a previously submerged appliance could result in property damage, severe personal injury, or death. NOTE: Appliance damage due to flood or submersion is considered an Act of God, and IS NOT covered under product warranty.
If overheating occurs or the gas supply fails to shut off, do not turn off electrical power to the circulating pump. This may aggravate the problem and increase the likelihood of boiler damage. Instead, shut off the gas supply to the boiler at the gas service valve. Failure to do so may result in property damage, personal injury, or death.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

D. User Interface Display Cascade Control Fault Codes
Screen

SYS SUPPLY SENSOR E03

PUMP OFF

12:56P

SUPPLY SENSOR PUMP ON

F02 TIME

RETURN SENSOR PUMP ON

F03 TIME

FLUE SENSOR PUMP ON

F04 TIME

Description

Possible Remedy

E03 indicates a problem with the system sensor circuit. The circuit could be open or shorted. Possible reasons for this error are: There is no system sensor connected to the Master Boiler. The system sensor is faulty. There is a short circuit in the system sensor wiring; possibly from a staple placed through the wire, or damage to the wire causing both conductors to touch. The system sensor wiring is open due to defect or damage.

Disconnect the system sensor from the wiring and measure it's resistance. Compare the measured resistance to the table in this manual to see if it corresponds to the temperature of the sensor. If the resistance does not agree with the sensor, replace the sensor. If the sensor is OK, disconnect the sensor wiring from both the boiler and the sensor and check continuity using an ohmmeter. Repair or replace as necessary. If this error is present, the boilers in the cascaded group will run and ignite simultaneously when there is a heat demand. Each boiler will modulate to maintain set point temperature on its own supply sensor. This code automatically resets when repair is complete. This code will not display if system setting function ERROR SYSTEM SENS is set to OFF.

The dual supply sensor contains two sensing elements within a single body. F02 indicates that one or both halves of the supply temperature sensor has failed OR the difference between the dual sensor readings is greater than 18oF. This is a serious safety issue and the boiler will not restart until the sensor is replaced by a technician and he pushes the RESET button on the display. This situation is indicated by the red light on the display and the flashing word LOCKOUT. During this lockout fault, the pump will be on as indicated on the second line of the display.

1. Check the electrical connections to each half of the sensor on the outlet manifold. Verify 3.3 VDC by checking in Molex connector. If there is not 3.3 VDC, check the harness. If harness and sensors are OK, replace control. NOTE: The boiler will reset automatically. Verify sensor resistance values of each half of the dual sensor by referencing chart in this manual. 2. Replace thermistor if necessary.

F03 indicates the return temperature sensor of the boiler has failed. The boiler will not restart until a technician replaces the sensor and pushes RESET on the display. This is a serious safety issue as indicated by the illuminated red light and the word LOCKOUT flashing on the display. During this lockout fault, the pump will be on.

1. Check circulator pump operation. 2. Ensure adequate flow through the boiler by accessing the status menu and determining there is less than a 50oF rise from the return thermistor to the supply thermistor. 3. Troubleshoot thermistor by following the steps in F02.

The dual flue sensor contains two sensing elements within a single body. F02 indicates that one or both halves of the flue temperature sensor has failed OR the difference between the dual sensor readings is greater than 18oF. This is a serious safety issue and the boiler will not restart until the sensor is replaced by a technician and he pushes the RESET button on the display. This situation is indicated by the red light on the display and the flashing word LOCKOUT. During this lockout fault, the pump will be on as indicated on the second line of the display.

1. Inspect the dual flue sensor for physical damage, blockage, or corrosion and replace it if necessary. 2. Check the electrical connection to the dual flue sensor and repair as necessary. Verify 3.3 VDC by checking in Molex connector. If there is not 3.3 VDC, check the harness. If harness and sensors are OK, replace control. NOTE: The boiler will reset automatically. Verify sensor resistance values of each half of the dual sensor by referencing chart in this manual. 3. Replace sensor if necessary.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

SUPPLY HIGH PUMP ON
RETURN TEMP HIGH PUMP ON
NO FLAME ON IGN PUMP ON
FLAME LOSS PUMP ON

F05 TIME
F06 TIME
F09 TIME
F10 TIME

F05 indicates the boiler supply temperature is excessive. When accompanied by the red FAULT light and LOCKOUT flashing on the display, this code indicates the supply sensor temperature has exceeded 210oF and a serious safety issue exists. The boiler will not restart until a technician determines and repairs the cause of excessive temperature and pushes RESET on the display. If the FAULT light is not illuminated and this message is displayed, the supply temperature of the boiler is at or above 199oF. The message will clear automatically when the temperature drops below 194oF. During the time that this fault is displayed, the pump will be on.

1. Check circulator pump operation. 2. Ensure adequate flow through the boiler by accessing the status menu and determining there is less than a 50°F rise from the return thermistor to the supply thermistor. 3. Check the direction of flow off the boiler circulator. (See Piping Details in this manual.) 4. Troubleshoot the dual supply thermistor by following steps in F02.

This display indicates that the boiler return temperature is excessive. When accompanied by the red FAULT light and LOCKOUT flashing on the display, this code indicates that the return sensor temperature has exceeded 210oF and a serious safety issue exists. The boiler will not restart until a technician determines and repairs the cause of excessive temperature and pushes RESET on the display. If the red FAULT light is not illuminated and this message is displayed, then the return temperature of the boiler is at or above 199oF. The message will clear automatically when the temperature drops below 194oF. During the time that this message or lockout fault is displayed, the pump will be on.

1. Check circulator pump operation. 2. Ensure adequate flow through the boiler by accessing the status menu and determining there is less than a 50°F rise from the return thermistor to the supply thermistor. 3. Check the direction of flow on boiler circulator. (See Piping Details in this manual.) 4. Troubleshoot thermistor by following steps in F02.

The boiler tried to ignite four times during one heat call and failed. This is a serious safety issue as indicated by the illuminated red light and the word LOCKOUT flashing on the display. The boiler will not restart until a technician determines and repairs the cause of ignition failure and pushes RESET on the display. During this lockout fault, the pump will remain on.

1. Watch the igniter through the observation window. 2. If there is no spark, check the spark electrode for the proper 1/4" gap between the burner. 3. Remove any corrosion from the spark electrode. 4. If there is a spark but no flame, check the gas supply to the boiler. 5. If there is a flame, check the flame current. 6. Check any flue blockage or condensate blocks. 7. Replace the ignitor.

The flame was lost 3 times while the boiler was firing during 1 demand call. This is a serious safety issue as indicated by the illuminated red light and the word LOCKOUT flashing on the display. The boiler will not restart until a technician determines and repairs the cause of flame loss and pushes RESET on the display. During this lockout fault, the pump will be on.

1. Monitor gas pressure to the unit while in operation. 2. Assure the flame is stable when lit. 3. Check if the display readout changes from "GAS VALVE ON" to "RUN" within a few seconds of boiler ignition. 4. Check the FLAME signal on the display. It should be above 2.5uA when the boiler is firing. 5. If the signal reads less than 2.5uA, clean the spark probe. 6. If the problem persists and the `FLAME" signal is still less than 2.5uA, replace the spark igniter probe. 7. The flame signal should be steady after the boiler has been firing for 1 minute and is normally at 5.0 to 9.0. If the flame signal is not steady, disassemble the burner door and check the burner and its sealing gaskets.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

62
FALSE FLAME SIG PUMP ON
FAN SPEED ERROR PUMP ON
FLUE LIMIT PUMP ON
CONDENSATE FULL PUMP OFF
LWCO FAULT PUMP OFF

F11 TIME
F13 TIME
F17 TIME
F20 TIME
F21 TIME

There is flame when the control is not telling the boiler to run. This is a serious safety issue as indicated by the illuminated red light and the word LOCKOUT flashing on the display. The boiler will not restart until a technician determines and repairs the cause and pushes RESET on the display. During this lockout fault, the pump will be on.

1. Look into window. If there is flame, turn the gas off to the unit at the service valve and replace the gas valve. 2. If the flame signal on the status menu is greater than 2.5uA when the burner is not lit, replace the spark ignitor. 3. If the flame signal is not present after turning off the gas supply, check the gas valve electrical connection. 4. Check for condensate backup. Repair condensate system as necessary. If condensate has partially filled the combustion chamber, the refractory wall may be damaged and should be replaced. 5. Turn the gas on at the service valve after corrective action is taken. 6. If the refractory wall falls against the spark ignitor, it may conduct the signal to ground, giving a false reading.

The fan is not running at the speed determined by the control. Fan speed has been more than 30% faster or slower than the commanded speed for more than 10 seconds. This is a serious safety issue as indicated by the illuminated red light and the word LOCKOUT flashing on the display. This boiler will not restart until a technician determines and repairs the cause and pushes RESET on the display. During this lockout fault, the pump will be on.

1. Check the combustion fan wiring. 2. Measure DC voltage from the red fan wire to ground while it is connected to the fan. It should be between 24 and 40 volts. If it is lower than 24 volts, check for excessive external loads connected to the boiler sensor terminals 3. Disconnect the 5 pin plug from the fan and check the voltage on the red wire again. If it is now between 24-40 volts, replace the fan. If it is still below 24 volts replace the boiler control board.

F17 indicates the boiler flue temperature is excessive. When accompanied by the red FAULT light and LOCKOUT flashing on the display, this code indicates the flue sensor temperature has exceeded 210oF and a serious safety issue exists. The boiler will not restart until a technician determines and repairs the cause of excessive temperature and pushes RESET on the display.

1. Check the flue for obstructions and any sign of damage, especially signs of excessive heat. Repair as necessary. 2. Run the boiler and check the flue temperature with an external thermometer. If the flue temperature on the thermometer does not agree with the flue temperature displayed in the status menu, inspect the wiring to the flue temperature sensor in the boiler and repair as necessary. If the wiring is intact replace the flue sensor. 3. If the flue temperature is excessive on the status menu and the test thermometer reads the same, check and adjust combustion controls on the boiler.

The condensate trap is full. This is a serious safety issue as indicated by the illuminated red light and the word LOCKOUT flashing on the display. The boiler will not restart until a technician determines and repairs the cause and pushes RESET on the display. During this lockout fault, the pump will be off.

1. Check condensate lines for obstructions. 2. Check float switch in condensate reservoir. 3. Check wiring from condensate reservoir to 928 control and repair as necessary.

Water level in the boiler is low.
To test LWCO function, press and hold v and RESET simultaneously for five (5) seconds. Press RESET to clear the error code.* *This procedure applicable to models with 928 control firmware ARBA-P 170426 or later or ASAA-P 170412 or later ONLY. NOTE: The date code is in YYMMDD format.

1. Check boiler feed water system to be sure it is supplying make-up water to the boiler system. 2. Ensure all air is bled from the system. 3. Check for leaks in the boiler and system piping and repair as necessary. 4. Inspect low water cutoff probe and wiring for damage and repair and replace as necessary.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

EXTERNAL LWCO PUMP ON

F22 TIME

TARGET WALL PUMP OFF

F24 TIME

GAS PRESSURE PUMP ON

F26 TIME

PROGRAM ERROR F31 PUMP OFF
HARD FAULT COND F41
HARD FAULT LWCO F42

This error is generated when the External Low Water Cut Off is installed and the water level in the boiler is low. When this code is displayed, the boiler will not respond to a demand for heat. The bottom line of the display indicates the status of the pump. The pump will remain on when this error is displayed.

IF EXT LWCO is installed: 1. Check boiler feed water system. Ensure it is supplying make-up water to the boiler system. 2. Be sure all air is bled from the system. 3. Check for leaks in the boiler and system piping and repair as necessary. 4. Inspect low water cut off wiring for damage and repair as necessary. 5. Ensure EXT LWCO has power applied to the power input terminals. 6. Press Reset button on LWCO. If error reoccurs, replace EXT LWCO. IF EXT LWCO is NOT installed: Inspect the jumper from terminals 20 and 21 on the Field Connection Board for damage or loose connections.

This error is generated when the target wall fuse has been disconnected or tripped on boilers 299kBTU or larger, or the target wall jumper wires are not installed on all other sizes.

For models 299/301/399: Check to ensure wires are connected to the target wall fuse. If wires are not connected, inspect the target wall in the combustion chamber and replace if damaged. For all other models: Check to ensure the jumper wire for target wall is connected on the control between wire locations X7-8 and X7-18.

The following switches are optional equipment that may be installed on boiler. These devices have indicator lights that illuminate if tripped. High gas pressure switch Trips if there is excessive gas pressure on the outlet side of the gas valve and must be manually reset. Low gas pressure switch Trips if there is low gas pressure on the inlet side of the gas valve and must be manually reset.

1. If an indicator light is illuminated, investigate the source of the error for that particular switch. 2. With boiler in service mode, measure the gas pressure in the supply line with a gas pressure meter. Monitor the gas pressure during both low and high fire conditions for correct pressure range. 3. If there are no optional switches or none of the indicator lights is illuminated on the optional switches, use an ohmmeter to test each of the switches one at a time. Turn the power off to the boiler and disconnect the switch to be tested from the boiler to determine which has tripped. When you find the tripped switch investigate the cause of the fault based on the purpose of the switch.

There was an error while programming the control and the memory is corrupt. The boiler control will not function in this state and the pump will be off as indicated on the bottom line. This error only occurs if a technician is programming the control and the programming function fails. The only way to recover from this error is to reprogram the control. If this error occurs at any time other than when a technician is servicing the boiler, the control has failed and must be replaced by a qualified technician.

The control must be reprogrammed. If programming does not solve the problem, the control must be replaced.

This error indicates there is an internal fault in the circuit within the control connected to the condensate switch.

1. Inspect the ground wires for damage or loose connections. 2. Inspect the condensate wiring for damage and repair as necessary. 3. Ensure no high voltage wires are routed in parallel with the condensate low voltage wiring. 4. Replace control.

This error indicates there is an internal fault in the LWCO circuit.

1. Inspect the ground wires for damage or loose connections. 2. Inspect the LWCO wiring for damage and repair as necessary. 3. Ensure no high voltage wires are routed in parallel with the LWCO low voltage wiring. 4. Replace control.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

AD SAFT FAULT

The temperature of either the flue or supply Ensure the connections to the flue and supply sensors

F43

sensors has risen nine degrees in 100 are intact. If wires are intact, check sensor resistance. If milliseconds and not returned to normal the problem persists or the sensors are out of normal

within 1 second.

resistance range, replace the sensors.

CONTROL PROGRAMED PP

The control has been programmed by a technician or the factory. After programming, Press RESET for at least 1 second to use the control. the control is left in a locked out mode.

OUTDOOR SENSOR PUMP ON

FOU 1:45P

There is an issue with the outdoor sensor. It is shorted, damaged, or disconnected from the boiler.

1. Check outdoor sensor connections and wiring. Ensure the sensor and wiring are intact and that the sensor is connected to the boiler. 2. Check the outdoor sensor resistance with an ohmmeter. See table in this manual for correct outdoor sensor resistance. 3. Replace the outdoor sensor.

The following blocking codes will block operation until the control determines the situation safe for boiler operation.

LOW WATER FLOW PUMP OFF

FL 4:32P

This indicates the flow switch is not activated.

1. Ensure boiler contains water and all valves are open. 2. Check the boiler circulator and ensure it is in good operating condition (operating, wiring intact, etc.). 3. Inspect the wiring to the flow switch for damage and repair as necessary. 4. Disconnect one wire from the flow switch and test for continuity across the switch while flow is confirmed to be present. 5. Remove flow switch and inspect switch paddle for proper operation.

FLUE TEMP HIGH PUMP ON

E07 TIME

This display indicates that the flue sensor temperature is above 210oF. When this code is displayed, the boiler will not respond to a demand for heat. When the flue temperature decreases below 194oF, the display will return to normal and allow the boiler to respond to a heat demand. The bottom line indicates the status of the pump. The pump will remain on when this error is displayed.

Check the flue for obstructions or any sign of damage, especially signs of excessive heat. Repair as necessary. Run the boiler and check the flue temperature with an external thermometer. If the flue temperature on the thermometer does not agree with the flue temperature displayed in the status menu, inspect the wiring to the flue temperature sensor in the boiler and repair as necessary. If the wiring is intact, replace the flue sensor. If the flue temperature is excessive on the status menu and the test thermometer reads the same, check and adjust combustion controls on the boiler.

TEMPER BLOCKING TT PUMP ON

TT indicates there is a demand for heat on the boiler, the pump is powered on, and the supply sensor temperature is too high for the boiler to ignite. This occurs because the water temperature measured by the supply sensor is higher than the tank temperature ignition diff setting.

This message will stay present until the water temperature measured by the supply sensor is less than the tank temperature ignition diff setting.

TEMPER BLOCKING PUMP ON

This screen indicates a demand for heat from the DHW circuit. The pump is powered on and the supply sensor temperature is too high for the boiler to ignite. This occurs because the water temperature measured by the supply sensor is higher than the tank temperature ignition diff setting. NOTE: If there is a CH demand while this screen is displayed, the screen may read:
TEMPER BLOCKING PRIO

This message will stay present until the water temperature measured by the supply sensor is less than the BOILER SUPPLY boiler supply differential (5oF) or DHW SETPOINT is satisfied and no longer calls for heat.

HIGH FLUE PRESS PUMP ON

FLU

FLU indicates excessive flue pressure. This code resets automatically after the high pressure condition is resolved. The second line indicates pump status.

1. Assure the flue is not blocked. 2. Check the switch wiring by applying a jumper in place of the switch. If the code clears with the jumper in place, REPLACE the flue switch and connect the wires to the new switch BEFORE running boiler.

WARNING: Do not use jumper to remedy an FLU error. Faulty switch MUST be replaced. Failure to follow this instruction could result in serious personal injury or death.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

FLUE TEMP HIGH PUMP OFF

E07 TIME

E07 indicates the flue sensor temperature is excessive and above 210oF. When E07 is displayed the boiler will not respond to a demand for heat and begin to modulate down on vent temp rather than supply temp. During reduced modulation, the display will show VENT RED MODULATION, and the second line will alternate between PUMP ON TIME and the actual vent temperature. When the flue temperature decreases below 194oF, the display will return to normal and allow the boiler to respond to a heat demand.

LINE VOLTAGE PUMP OFF

E19 indicates the line voltage frequency is

E19

out of range. This could happen if the boiler is being powered from a small gasoline

powered generator that is overloaded or not

functioning correctly.

Table 32 - Boiler Error and Fault Codes

Inspect power wiring to the boiler and repair as necessary. If connected to line voltage, notify the power company. If connected to an alternate power source such as a generator or inverter, make sure the line voltage frequency supplied by the device is 47 - 62.5 Hz.

Outdoor Sensor (7250P-319)

Temperature (oF)
-22 -13 -4 5 14 23 32 41 50 59 68 77 86 95 104 113

Resistance (ohms) 171800 129800 98930 76020 58880 45950 36130 28600 22800 18300 14770 12000 9804 8054 6652 5522

Table 33 - Sensor Temperature Resistance

Supply Temperature Sensor
(7700P-073)

Indirect Sensor (7250P-325)

Temperature (oF)
32 41 50 59 68 77 86 95 104 113 122 131 140 149 158 167 176 185 194 203 212

Return Sensor (7250P-
667)

Dual Flue Temperature Sensor (7450P-176)

Resistance (ohms)

32624 25381 19897 15711 12493 10000 8056 6530 5324 4365 3599 2982 2483 2079 1748 1476 1252 1066
912 782 674

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 13 - Maintenance
A. Procedures Periodic maintenance should be performed once a year by a qualified service technician to assure that all the equipment is operating safely and efficiently. The owner should make necessary arrangements with a qualified heating contractor for periodic maintenance of the boiler. The installer must also inform the owner that a lack of proper care and maintenance of the boiler may result in a hazardous condition.
BEFORE EACH HEATING SEASON a trained and qualified service technician should perform the inspections as per the boiler inspection and maintenance schedule in this manual. Failure to do so could result in death or serious injury.
The combustion chamber insulation in this product contains ceramic fiber material. Ceramic fibers can be converted to cristobalite in very high temperature applications. The International Agency for Research on Cancer (IARC) has concluded, "Crystalline silica inhaled in the form of quartz or cristobalite from occupational sources is carcinogenic to humans (Group 1)." · Avoid breathing dust and contact with skin and eyes. · Use a NIOSH certified dust respirator (N95). This type of
respirator is based on the OSHA requirements for cristobalite at the time this document was written. Other types of respirators may be needed depending on job site conditions. Current NIOSH recommendations can be found on the NIOSH website: http://www.cdc.gov/niosh/homepage.html. NIOSH approved respirators, manufacturers, and phone numbers are also listed on this website. · Wear long-sleeved, loose fitting clothing, gloves, and eye protection. · Apply enough water to the combustion chamber lining to prevent dust. · Wash potentially contaminated clothes separately from other clothing. Rinse clothes washer thoroughly. NIOSH stated First Aid. · Eye: Irrigate immediately. · Breathing: Fresh air.
B. Combustion Chamber Coil Cleaning Instructions *Before beginning this procedure, have on hand the following items:
· a nylon, stainless steel, or brass brush (not steel) · an FDA approved liquid lime scale remover in a spray bottle · gloves and eye protection 1. Shut down the boiler by using the following steps:
a. Close the gas valve. Shut down the unit, and wait for it to be cool to the touch. b. Disconnect the condensate piping from the outside connection, (not from the boiler side), so flow from condensate reservoir can be observed. c. Disconnect electrical connections from the gas valve, spark electrode, flame rectification probe, and combustion blower. d. Remove the four (4) screws on the aluminum ¾" NPT connector on the right side of the gas valve. e. Disconnect the wiring connected to the combustion blower motor. f. Remove the six (6) 10MM nuts from the burner plate assembly. g. Pull the entire burner plate assembly with blower still attached towards you, while removing or pushing aside any wiring to allow removal of the assembly. 2. Spray the coils liberally with the FDA approved liquid lime scale remover. Confine the spray to the area being cleaned. Avoid getting the ceramic target wall wet. If the condensate system is blocked, use a vacuum to clear it. 3. Scrub coils of any buildup with a nylon, stainless steel, or brass brush.

Do not use a steel brush. Vacuum the debris from the coils. 4. Spray the coils again with clear tap water. Confine the spray to the area being cleaned. Flush the combustion chamber with fresh water until it runs clear from the condensate reservoir. At this point, the boiler should be ready to be reassembled.
a. Inspect gaskets. b. Reinstall the burner assembly c. Replace and tighten the six (6) 10MM nuts to the burner plate using staggered tightening sequence. (See detail.) d. Reconnect all wiring connections e. Inspect the gas valve. Ensure the O-ring is in place. f. Replace the four (4) screws on the aluminum connector on the gas valve. Turn the gas back on. (IMPORTANT: CHECK FOR GAS LEAKS!) g. Turn boiler power back on and create a heat demand. When boiler is lit observe condensate flow from the boiler. Be sure the boiler is operating properly. h. Reconnect the condensate piping to the outside condensate connection.
Do not use solvents to clean any of the burner components. The components could be damaged, resulting in unreliable or unsafe boiler operation, substantial property damage, severe personal injury, or death.
Figure 31 - Heat Exchanger Detail
C. Cleaning Water Side of Heat Exchanger 1. Make sure power is turned off to the boiler. Run water through the hot water system to ensure it is below room temperature. 2. Close isolation valves on the return and supply connections to the boilers as shown in the piping diagrams in this manual. Slowly open the ball valves and release pressure into a bucket. Once pressure is released, connect a hose to the water line to flush the boiler. Scale removing solution may be used, but must be approved for use with stainless steel and FDA approved for use in a potable water system. 3. Thoroughly flush the heat exchanger before commissioning the unit back in service.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

67
D. Maintaining the Condensate System 1. Ensure the boiler is powered off and has had time to cool. 2. Remove the hose clamp attaching the condensate trap to the condensate hose from the heat exchanger. Remove the clear plastic hose from the hose barb. Remove the condensate hose clamp to detach the condensate trap from the drain tube. Remove the condensate trap from the boiler. 3. Remove the bottom cap from the condensate trap. 4. Flush trap with fresh water to remove debris from the trap. NOTE: Ensure the float moves freely within the trap. If the float does not move, DO NOT reinstall the trap. 5. When the condensate trap is sufficiently clean, reinstall the bottom cap on the trap. NOTE: Ensure all parts shown in Figure 32, Condensate Detail, are installed with the condensate trap. If any parts are missing, DO NOT reinstall the trap. Replace the entire assembly.
The condensate trap assembly MUST BE PROPERLY INSTALLED according to these instructions when operating the boiler. Operating the boiler without the condensate trap assembly will cause flue gases to leak and result in serious personal injury or death. When servicing is complete, make sure the condensate collector cap is replaced securely. Failure to do so will cause venting issues that will result in serious injury or death.

Do not install the condensate assembly if a component is lost or missing. Replace the entire assembly. Failure to follow this warning could result in property damage, serious personal injury, or death.

6. Fill the condensate trap with fresh water prior to reassembly on the boiler. 7. Install the condensate trap on the condensate hose from the heat exchanger. Use the hose clamp to secure the trap. Attach the clear plastic hose onto the hose barb. Reinstall the condensate hose clamp to detach the condensate trap from the drain tube. 8. If a condensate neutralizer kit is installed with the boiler, check the assembly when cleaning the condensate trap, and replenish the limestone chips if necessary. When replacing limestone chips, take care to ensure chips are no smaller than ½" to avoid blockage in condensate piping (for piping details, refer to condensate neutralizer installation instruction.) 9. Check condensate piping for sagging and/or leakage. Repair any sags or leaks before restoring power to the boiler.

Figure 32 - Condensate Detail

Do not operate the boiler without the clear hose attached from the hose barb to the pressure switch. Failure to follow this warning could result in property damage, serious personal injury, or death.
It is very important that the condensate piping be no smaller than ¾". To prevent sagging and maintain pitch, condensate piping should be supported with pipe supports, and pitched ¼" per foot to allow for proper drainage. Failure to maintain proper pipe size and pitch could result in condensate leakage and potential water damage to property. The condensate line must remain unobstructed, allowing free flow of condensate. If condensate freezes in the line, or if line is obstructed in any other manner, condensate can exit from the tee, resulting in potential water damage to property. 10. If the boiler has a condensate pump, ensure the pump operates properly before considering maintenance complete.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 14 - Installation Checklist

Light Off Activities

Date Completed:

Check all piping and gas connections. Verify all are tight.

Pressurize system.

PSI

1. Fill the Heating System

Add water to prime condensate cup.

Verify near boiler piping is properly supported.

Leak test using locally approved methods (consult jurisdictional code book).

2. Check Gas Pipe

Check incoming gas pressure (3.5 to 14"WC).

Static WC

Check the "drop" on light off (less than 1" WC).

Dynamic WC

3. Check Combustion

Check and adjust (if necessary) carbon dioxide content.
Check and adjust (if necessary) carbon monoxide content.

%CO2 High Fire ppm CO High Fire

4. Check Electrical Connections

Ensure all electrical connections of line voltage (pumps, etc.) and low voltage circuits (system sensor, outdoor sensor, etc.) are properly wired.

5. Verify System Operation

Turn up thermostat connections.

verify

wiring

6. Record Ionization Current

Check uA reading at d7 on the status menu (see Start-Up section, this manual).

uA High Fire

7. Indirect Water Heater

Verify safety and operation of the indirect water heater. Record settings.

DHW Setpoint

8. Mixing Valve

If necessary, ensure thermostatic mixing valve is properly supported and installed.

If necessary, convert the boiler to the proper fuel type.

Locate the stickers in the appropriate locations on the boiler.

9. Convert the Boiler

Verify combustion settings after gas conversion - Carbon Dioxide.

%CO2 High Fire

Verify combustion settings after gas conversion - Carbon Monoxide.

ppm CO High Fire

Mail in conversion registration.

10.

Record heating curve. Record steps

Notes:

%CO2 Low Fire ppm CO Low Fire
uA Low Fire DHW Differential

%CO2 Low Fire ppm CO Low Fire

*10

*11

Table 34 - Installation Checklist

Part 15 - Maintenance Report
In unusually dirty or dusty conditions, care must be taken to keep boiler cabinet door in place at all times. Failure to do so VOIDS the warranty.
Allowing the boiler to operate with a dirty combustion chamber will hurt operation. Failure to clean the heat exchanger as needed by the installation location could result in boiler failure, property damage, personal injury, or death. Such product failures ARE NOT covered under warranty.

The boiler requires minimal periodic maintenance under normal conditions. However, in unusually dirty or dusty conditions, periodic vacuuming of the cover to maintain visibility of the display and indicators is recommended. Periodic maintenance should be performed once a year by a qualified service technician to assure that all the equipment is operating safely and efficiently. The owner should make necessary arrangements with a qualified heating contractor for periodic maintenance of the boiler. Installer must also inform the owner that the lack of proper care and maintenance of the boiler may result in a hazardous condition.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Inspection Activities

Date Last Completed

Piping

1st Year 2nd Year 3rd Year 4th Year*

Near boiler piping

Check boiler and system piping for any sign of leakage; make sure pipes are properly supported.

Vent

Check condition of all vent pipes and joints. Ensure the vent piping terminations are free of obstructions and blockages.

System

1st Year 2nd Year 3rd Year 4th Year*

Visual

Do a full visual inspection of all system components.

Functional

Test all functions of the system (Heat, Safeties).

Temperatures

Verify safe settings on boiler or anti-scald valve. Verify programmed temperature settings.

Electrical

Connections

Check wire connections. Make sure connections are tight.

Smoke and CO Detector

Verify devices are installed and working properly. Change batteries if necessary.

Circuit Breakers

Check to see that the circuit breaker is clearly labeled. Exercise circuit breaker.

Chamber / Burner

1st Year 2nd Year 3rd Year 4th Year*

Combustion Chamber

Check burner tube and combustion chamber coils. Clean according to maintenance section of manual. Vacuum combustion chamber. Replace any gaskets that show signs of damage.

Spark Electrode

Clean. Set gap at 1/4" Clean probe with plumbers cloth to remove oxides.

Combination Ignitor and Flame Probe

Check ionization in uA (d7 in Status Menu in Start-Up Procedures). Record high fire and low fire. Clean probe with plumbers cloth to remove oxides.

Condensate

1st Year 2nd Year 3rd Year 4th Year*

Neutralizer

Check condensate neutralizer. Replace if necessary.

Condensate Pipe

Disconnect condensate pipe. Clean out dirt. Fill with water to level of outlet and reinstall. (NOTE: Verify the flow of condensate, making sure that the hose is properly connected during final inspection.)

Gas

1st Year 2nd Year 3rd Year 4th Year*

Pressure

Measure incoming gas pressure (3.5 to 14" WC).

Pressure Drop

Measure drop in pressure on light off (no more than 1" WC).

Check Gas Pipe for Check gas piping. Test for leaks and signs of aging. Make sure all pipes

Leaks

are properly supported.

Combustion

1st Year 2nd Year 3rd Year 4th Year*

CO / CO2 Levels

Check CO and CO2 levels in exhaust. See Start-Up Procedures for ranges. Record at high and low fire.

Safeties

1st Year 2nd Year 3rd Year 4th Year*

ECO (Energy Cut Check continuity on flue and water ECO. Replace if corroded. Out)

Sensors

Check wiring. Verify through ohms reading.

Final Inspection

1st Year 2nd Year 3rd Year 4th Year*

Check List

Verify that you have completed entire check list. WARNING: FAILURE TO DO SO COULD RESULT IN SERIOUS INJURY OR DEATH.

Homeowner

Review what you have done with the homeowner.

Table 35 - *Continue annual maintenance beyond the 4th year as required.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

Part 16 - Replacement Parts

ITEM # 1 2 3 4 5 6 7 8 9 10 11 12
13 14
15 16 17 18 19 20 21 22 23 24 25 26 27
28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43

110

150

220

Description

7450P-001 7450P-002 7450P-003 7450P-004 BOILER MODULE

7250P-160

CERAMIC TARGET WALL

7500P-109

M4 FLAT WASHER

7250P-704

M4 X 8 FLAT HEAD SCREW

7450P-300

BURNER DOOR

7450P-005

BURNER DOOR INSULATION

7450P-009 7450P-010 7450P-011 7450P-012 BURNER

7500P-074

GASKET - BURNER

7450P-008

7450P-007

AIR CHANNEL

7250P-206

M5 X 14MM TORX SCREWS - AIR CHANNEL

7500P-075

GASKET - AIR CHANNEL/BLOWER

7500P-195

7700P-102

COMBUSTION BLOWER (NATURAL GAS) 7350P-159
COMBUSTION BLOWER (LP)

7250P-478

M5 X 12MM SOCKET CAP SCREW

7450P-361 7450P-363 7450P-365 7450P-367 AIR/GAS MIXER (NATURAL GAS)

7450P-362 7450P-364 7450P-366 7450P-368 AIR/GAS MIXER (LP)

7450P-141

7500P-099 SCREWS - AIR/GAS MIXER

7450P-115

8600P-044 WASHER - AIR/GAS MIXER

7700P-072

7450P-407 FLARE X BSP FITTING

7100P-140

7450P-140 FLEXIBLE GAS LINE

7450P-907

GAS VALVE

7450P-154

7450P-143 FLARE X NPT FITTING

N/A

9500P-0030* 1/2" X CLOSE NIPPLE (LOCATION SHOWN)

7500P-067

M6 NUT - BURNER DOOR

7250P-005

GASKET - PROBE/ELECTRODE

7350P-020

SPARK ELECTRODE (W/GASKET)

7250P-069

SCREW M4 X 8MM - PROBE/ELECTRODE

7350P-022

FLAME RECTIFICATION PROBE (W/GASKET)

7250P-667

THERMISTOR

7450P-280

THERMISTOR - VWH ONLY

7250P-096

WATER PRESSURE SWITCH - NPT THREAD

7700P-073

DUAL SUPPLY SENSOR

7450P-185

7500P-057

CONDENSATE HOSE

7450P-094

7450P-095

CONDENSATE COLLECTOR ASSY

7250P-210

HOSE CLAMP

7450P-199

1/4" NPT NIPPLE

7450P-197

AIR RELEASE VENT

7100P-044

NPT X HOSE BARB FITTING

7700P-002

1/2" NPT NUT

7450P-086

1/2" NPT X 3/4 PVC SWEAT ADAPTER

7250P-154

S.S. HOSE BARB - BLOCKED VENT PRESSURE SWITCH

7250P-152

O-RING - HOSE BARB

7250P-153

S.S. 10-32 HEX NUT

7450P-404

O - RING - GAS VALVE ADAPTER

7450P-402

GAS VALVE ADAPTER

7450P-406

SCREWS - GAS VALVE ADAPTER

39 40

9 10

23 24

19 43

13 15

2 32
31

LP-550-Q 03/17/21

42 41

21*

14 35 17 16 12

32 36

Figure 33 - Combustion System Replacement Parts - 80 - 220kBTU Models

LP-550 Rev. 000 Rel. 022 Date 4.2.21

71
1 31
30

7 8 10 11 12

32 33

18 37

21 20

ITEM# 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
19

299

301

399

DESCRIPTION

7450P-014 7450P-015 BOILER MODULE

7250P-160

CERAMIC TARGET WALL

7500P-109

WASHER, FLAT M4 - TARGET WALL

7250P-704

SCREWS M4 X 8 FLAT HEAD - TARGET WALL

7450P-005

BURNER DOOR INSULATION

7450P-300

BURNER DOOR

7350P-031

BURNER - GFCI

7500P-074 7500P-067

GASKET - BURNER NUT M6 - BURNER DOOR

7450P-007

AIR CHANNEL

7250P-206

TORX SCREWS M5 X 14MM - AIR CHANNEL

7250P-005 7350P-020 7250P-069 7350P-022 7500P-075 7350P-159 7250P-478

GASKET - PROBE/ELECTRODE SPARK ELECTRODE W/GASKET SCREWS M4 X 8MM - PROBE/ELECTRODE FLAME RECTIFICATION PROBE W/GASKET GASKET - AIR CHANNEL/BLOWER COMBUSTION BLOWER SCREWS M5 X 12MM - BLOWER

7450P-369 7450P-371 AIR/GAS MIXER (NATURAL GAS)

7450P-370 7450P-372 AIR/GAS MIXER (LP GAS)

ITEM# 20 21 22 23 24 25 26 27 28 29
30
31 32 33 34 35 36 37 38

299

301

399

8600P-044

7450P-407

7450P-140

7450P-143

9500P-0030

7450P-908

7450P-404

7450P-403

7450P-332

7700P-073

7250P-096

7450P-133

7250P-667

7250P-210

7500P-057

7450P-095

7100P-044

7700P-002

7450P-086

7450P-085

GASKET - FLARE X BSP FITTING FLARE X BSP FITTING FLEXIBLE GAS LINE FLARE X NPT FITTING CLOSE NIPPLE - 1/2" GAS VALVE O-RING - GAS VALVE ADAPTER GAS VALVE ADAPTER SCREWS - GAS VALVE ADAPTER DUAL SUPPLY SENSOR WATER PRESSURE SWITCH (NPT THREAD) BRASS PLUG - (VWH ONLY) THERMISTOR HOSE CLAMP CONDENSATE HOSE CONDENSATE TRAP KIT HOSE BARB X 1/2" NPT LOCKNUT - 1/2" PVC ADAPTER - 3/4" X 1/2" FNPT FLUE ECO SWITCH - 160 DEGREES

Figure 34 - Combustion System Replacement Parts - 299 - 399kBTU Models

LP-550-R 03/17/21

LP-550 Rev. 000 Rel. 022 Date 4.2.21

72
Figure 35 - Cabinet Replacement Parts - All Models
LP-550 Rev. 000 Rel. 022 Date 4.2.21

LP-550-V

12/19/18

3 19
18

12 6 7

5
11 9 8 10
12

14 9

ITEM #

110

150

220

7450P-282

7450P-201

7450P-176

7450P-030

7450P-032

7450P-028

7450P-021

SEE C HA RT

7500P-115

7250P-378

7250P-150

7450P-142

7350P-370

6300P-037

7450P-902

7000P-805

7450P-352

7450P-354

7450P-353

7450P-355

7250P-154

7250P-152

7450P-093

Figure 36 - Cabinet Replacement Parts - All Models

299/301

399

7450P-157

7450P-324

7450P-031 7450P-033

7450P-903

7450P-356 7450P-357

7450P-358 7450P-359

DESC RIPTIO N C LA M P A LL - EXHA UST V ENT A DA PTER EXHA UST A DA PTER DUA L FLUE SENSO R A IR INLET A DA PTER A IR INLET C O NNEC TO R NUT DISPLA Y BO A RD M EM BRA NE TO UC HPA D C O NTRO L BO A RD 6-32 X 1/ 4 PA D HEA D SC REW - ELEC TRO NIC BO A RDS FUSE - C O NTRO L BO A RD - 6.3 A M PS PRESSURE SW ITC H 6-32 FLA NG ED NUT - PRESSURE SW ITC H FIELD C O NNEC TIO N BO A RD FUSE - FIELD C O NNEC TIO N BO A RD - 2.0 A M PS FLUE KIT (inc lud e s: ite m s # 1, 2, 3) PLA STIC TUBING - PRESSURE SW ITC HES (NO T SHO W N) 120V WIRING HARNESS (NOT SHOWN) LOW VOLTAGE WIRING HARNESS (NOT SHOWN) HO SE BA RB O -RING - HO SE BA RB RIBBO N C A BLE - DISPLA Y BO A RD (NO T SHO W N)

LP-550 Rev. 000 Rel. 022 Date 4.2.21

74
Model
80,000 BTU 110,000 BTU 150,000 BTU 220,000 BTU 299,000 BTU / 301,000 BTU 399,000 BTU Table 36 - Control Board Part Numbers

Control Board Part Numbers

7450P-2101

7450P-2100

7450P-2103

7450P-2102

7450P-2105

7450P-2104

7450P-2108

7450P-2106

7450P-2112

7450P-2110

7450P-2116

7450P-2114

LP-550 Rev. 000 Rel. 022 Date 4.2.21

EliteTM Boiler Limited Warranty Twelve year warranty to assure your complete satisfaction.
HTP warrants this boiler and its components to be free from defects in material and workmanship according to the following terms, conditions, and time periods. UNLESS OTHERWISE NOTED THESE WARRANTIES COMMENCE ON THE DATE OF INSTALLATION. This limited warranty is only available to the original consumer purchaser (herinafter"Owner") of this boiler, and is non-transferable.
COVERAGE A. During the first year after the date of installation, HTP warrants that it will repair or replace, at its option, any defective or malfunctioning component of the boiler that is found to have failed due to manufacturer's defect. Replacement components will be warranted for ninety (90) days. No other component of the boiler will be replaced after this period (with exception to the blower motor, which will have a limited warranty of three [3] years). B. During the first through seventh year after the date of installation, should a defect or malfunction result in a leakage of water from the boiler due to defective material or workmanship, malfunction, or failure to comply with the above warranty, with such defect or malfunction having been verified by an authorized HTP representative, HTP will repair or replace, at its option, the defective or malfunctioning boiler. Replacements will be of the nearest comparable model available at the time of replacement. The replacement boiler will be warranted for the unexpired portion of the applicable warranty period of the original boiler. C. During the eighth through twelfth year after the date of installation, should a defect or malfunction result in a leakage of water from the boiler due to defective material or workmanship, malfunction, or failure to comply with the above warranty, with such defect or malfunction having been verified by an authorized HTP representative, HTP will repair or replace, at its option, the defective or malfunctioning boiler at a cost to the Owner equal to the following percentages of the manufacturer's list price in effect at the date of replacement:

Year of Claim

1-7

Percentage to be Paid by Owner

0 %

8 & 9 25 %

10 & 11 50 %

12 75 %

Replacements will be of the nearest comparable model available at the time of replacement. The replacement boiler will be warranted for the unexpired portion of the applicable warranty period of the original boiler. D. In the event of a leakage of water of a replacement boiler due to defective material or workmanship, malfunction, or failure to comply with the above warranty, HTP reserves the right to refund to the Owner the published wholesale price available at the date of manufacture of the original boiler. E. If government regulations, industry certification, or similar standards require the replacement boiler or component(s) to have features not found in the defective boiler or component(s), the Owner will be charged the difference in price represented by those required features. If the Owner pays the price difference for those required features and/or to upgrade the size and/or other features available on a new replacement boiler or component(s), the Owner will also receive a complete new limited warranty for that replacement boiler or component(s). F. If at the time of a request for service the Owner cannot provide a copy of the original sales receipt or the warranty registration, the warranty period for the boiler shall then be deemed to have commenced thirty (30) days after the date of manufacture of the boiler and NOT the date of installation of the boiler, and be covered

by the unexpired portion of the warranty detailed above. G. This warranty extends only to boilers utilized in closed loop heating applications that have been properly installed based upon the manufacturer's installation instructions. H. It is expressly agreed between HTP and the Owner that repair, replacement, or refund are the exclusive remedies of the Owner.
OWNER RESPONSIBILITIES The Owner or Qualified Installer / Service Technician must: 1. Have a relief valve bearing the listing marks of the American Society of Mechanical Engineers (ASME) installed with the boiler assembly in accordance with federal, state, and local codes. 2. Maintain the boiler in accordance with the maintenance procedure listed in the manufacturer's provided instructions. Preventive maintenance can help avoid any unnecessary breakdown of the boiler and keep it running at optimum efficiency. 3. Maintain all related system components in good operating condition. 4. Check all condensate lines to confirm that all condensate drains properly from the boiler. 5. Use the boiler in a closed system with a properly sized and installed thermal expansion tank. 6. Use the boiler at water pressures not exceeding the working pressure shown on the rating plate. 7. Keep the boiler free of damaging scale deposits. 8. Make provisions so if the boiler or any component or connection thereto should leak, the resulting flow of water will not cause damage to the area in which it is installed.
WARRANTY EXCLUSIONS This limited warranty will not cover: 1. Any boiler purchased from an unauthorized dealer. 2. Any boiler not installed by a qualified heating installer/service technician, or installations that do not conform to ANSI, CSA, and/ or UL standards, as well as any applicable national or local building codes. 3. Service trips to teach the Owner how to install, use, maintain, or to bring the boiler installation into compliance with local building codes and regulations. 4. The workmanship of any installer. The manufacturer disclaims and does not assume any liability of any nature caused by improper installation, repair, or maintenance. 5. Electricity or fuel costs, or increased or unrealized savings for same, for any reason whatsoever. 6. Any water damage arising, directly or indirectly, from any defect in the boiler or component part(s) or from its use. 7. Any incidental, consequential, special, or contingent damages or expenses arising, directly or indirectly, from any defect in the boiler or the use of the boiler. 8. Failure to locate the boiler in an area where leakage of the boiler or water line connections and the relief valve will not result in damage to the area adjacent to the boiler or lower floors of the structure, as well as failure to install the boiler with properly designed containment measures. 9. Any failed components of the system not manufactured by HTP as part of the boiler. 10. Boilers repaired or altered without the prior written approval of HTP. 11. Damages, malfunctions, or failures resulting from failure to install the boiler in accordance with applicable building codes/ordinances or good plumbing and electrical trade practices. 12. Damages, malfunctions, or failures resulting from improper installation, failure to operate the boiler at firing rates or pressures not exceeding those on the rating plate, or failure to operate and maintain the boiler in accordance with the manufacturer's provided instructions. 13. Failure to operate the boiler in a closed system with a properly

LP-550 Rev. 000 Rel. 022 Date 4.2.21

sized and installed thermal expansion tank. 14. Failure or performance problems caused by improper sizing of the boiler, expansion device, piping, or the gas supply line, the venting connection, combustion air openings, electric service voltage, wiring or fusing. 15. Damages, malfunctions, or failures caused by improper conversion from natural gas to LP gas or LP gas to natural gas. 16. Damages, malfunctions, or failures caused by operating the boiler with modified, altered, or unapproved components, or any component / attachment not supplied by HTP. 17. Damages, malfunctions, or failures caused by abuse, accident, fire, flood, freeze, lightning, electrochemical reaction, acts of God and the like. 18. Failures (leaks) caused by operating the boiler in a corrosive or contaminated atmosphere. 19. Damages, malfunctions, or failures caused by operating an empty or partially empty boiler ("dry firing"), or failures caused by operating the boiler when it is not supplied with water, free to circulate at all times. 20. Any damage or failure of the boiler due to the accumulation of solid materials or lime deposits. 21. Any damage or failure resulting from improper water chemistry. WATER CHEMISTRY REQUIREMENTS Water pH between 6.5 and 8.5. Hardness less than 7 grains (120 mg/L). Chloride concentration less than 100 ppm (mg/L). TDS less than 500 ppm (mg/L). 22. Any damages, malfunctions, or failures resulting from the use of galvanized unions. 23. Boilers replaced for cosmetic reasons. 24. Components of the boiler that are not defective, but must be replaced during the warranty period as a result of reasonable wear and tear. 25. Components of the boiler that are subject to warranties, if any, given by their manufacturers; HTP does not adopt these warranties. 26. Damages, malfunctions, or failures resulting from the use of any attachment(s) not supplied by HTP. 27. Boilers installed outside the fifty states (and the District of Columbia) of the United States of America and Canada. 28. Boilers moved from the original installation location. 29. Boilers that have had their rating labels removed.
PROCEDURES FOR WARRANTY SERVICE REQUESTS Any claim for warranty assistance must be made immediately upon finding the issue. First, please consult the HTP Warranty Wizard (http://www.htproducts.com/Warranty-Wizard.html) to check warranty eligibility. You may also contact HTP Technical Support at 1-800-323-9651 for questions or assistance. Warranty coverage requires review and approval of the issue with HTP Technical Support or through the Warranty Wizard prior to a full unit replacement. Any claim for warranty reimbursement will be rejected if prior approval from HTP is not obtained in advance of a full unit replacement. Final determination will be made as part of the warranty claim process. When submitting a warranty claim the following items are required:
1. Proof of purchase or installation of the product Typically a copy of the invoice from the installing contractor, the receipt of the purchase of the product, or an original certificate of occupancy for a new home. 2. Clear pictures (or video) of the following:
a. Serial number tag (sticker) b. The product c. The product issue / failure whenever possible d. A picture of the piping near the product e. For gas fired products, a picture of the venting, including how it exits the building All claims will be reviewed by HTP within three (3) business days. If additional information is required and requested by the HTP Claims Department you will have thirty (30) days to provide it. When all

requested information is provided HTP will respond within three (3) business days. The claim will be automatically closed if requested information is not provided within thirty (30) days. Claims will not be reopened without HTP Warranty Supervisor approval. During the claims process a product that must be replaced will be given a designation of either a) field scrap, or b) return to HTP. If the product must be returned to HTP, the returned product must arrive at HTP within thirty (30) days of the date of our request to return the product. After receipt of the returned product HTP may require as many as thirty (30) additional days for product testing. NOTE: Any components or heaters returned to HTP for warranty analysis will become the property of HTP and will not be returned, even if credit is denied. If you have questions about the coverage of this warranty, please contact HTP at the following address or phone number: HTP, 272 Duchaine Blvd., New Bedford, MA, 02745, Attention: Warranty Service Department, 1(800) 323-9651.
SERVICE, LABOR AND SHIPPING COSTS Except when specifically prohibited by the applicable state law, the Owner, and not the Manufacturer, shall be liable for and shall pay for all charges for labor or other expenses incurred in the removal, repair, or replacement of the boiler or any component part(s) claimed to be defective or any expense incurred to remedy any defect in the product. Such charges include, but are not necessarily limited to:
1. All freight, shipping, handling, and delivery costs of forwarding a new boiler or replacement part(s) to the owner. 2. All costs necessary or incidental in removing the defective boiler or component part(s) and installing a new boiler or replacement part(s). 3. All administrative fees incurred by the Owner, as well as material required to complete, and/or permits required for, installation of a new boiler or replacement part(s), and 4. All costs necessary or incidental in returning the defective boiler or component part(s) to a location designated by the manufacturer.
LIMITATIONS OF THIS HTP WARRANTY AND REMEDIES THE FOREGOING WARRANTIES ARE EXCLUSIVE AND ARE GIVEN AND ACCEPTED TO THE FURTHEST EXTENT UNDER APPLICABLE LAW IN LIEU OF ANY AND ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE AND ANY OBLIGATION, LIABILITY, RIGHT, CLAIM OR REMEDY IN CONTRACT OR TORT, WHETHER OR NOT ARISING FROM HTP'S NEGLIGENCE, ACTUAL OR IMPUTED. THE REMEDIES OF THE OWNER SHALL BE LIMITED TO THOSE PROVIDED HEREIN TO THE EXCLUSION OF ANY OTHER REMEDIES INCLUDING WITHOUT LIMITATION, INCIDENTAL OR CONSEQUENTIAL DAMAGES, SAID INCIDENTAL AND CONSEQUENTIAL DAMAGES INCLUDING, BUT NOT LIMITED TO, PROPERTY DAMAGE, LOST PROFIT OR DAMAGES ALLEGED TO HAVE BEEN CAUSED BY ANY FAILURE OF HTP TO MEET ANY OBLIGATION UNDER THIS AGREEMENT INCLUDING THE OBLIGATION TO REPAIR AND REPLACE SET FORTH ABOVE. NO AGREEMENT VARYING OR EXTENDING THE FOREGOING WARRANTIES, REMEDIES OR THIS LIMITATION WILL BE BINDING UPON HTP. UNLESS IN WRITING AND SIGNED BY A DULY AUTHORIZED OFFICER OF HTP. THE WARRANTIES STATED HEREIN ARE NOT TRANSFERABLE AND SHALL BE FOR THE BENEFIT OF THE ORIGINAL OWNER ONLY.
NO OTHER EXPRESS WARRANTIES This warranty gives the Owner specific legal rights. The Owner may also have other rights that vary from state to state. Some states do not allow the exclusion or limitation of incidental or consequential damages so this limitation or exclusion may not apply to the Owner. These are the only written warranties applicable to this boiler manufactured and sold by HTP. HTP neither assumes nor authorizes anyone to assume for it any other obligation or liability in connection with said boilers. HTP reserves the right to change specifications or discontinue models without notice.

LP-550 Rev. 000 Rel. 022 Date 4.2.21

77 Maintenance Notes
LP-550 Rev. 000 Rel. 022 Date 4.2.21

78 Customer Installation Record Form
The following form should be completed by the qualified installer / service technician for you to keep as a record of the installation in case of a warranty claim. After reading the important notes at the bottom of the page, please also sign this document. Customer's Name Date of Installation Installation Address Product Name / Serial Number(s)
Comments
Installer's Code / Name Installers Phone Number Signed by Installer Signed by Customer
Installation Notes
IMPORTANT Customer: Please only sign after the qualified installer / service technician has fully reviewed the installation, safety, proper operation, and maintenance of the system. If the system has any problems please call the qualified installer / service technician. If you are unable to make contact, please call your sales representative. Distributor / Dealer: Please insert contact details.
LP-550 Rev. 000 Rel. 022 Date 4.2.21

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