Lennox International Inc G50Uh 24A 045 Users Manual

LENNOX Furnace/Heater, Gas Manual L0806179 LENNOX Furnace/Heater, Gas Owner's Manual, LENNOX Furnace/Heater, Gas installation guides

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,1_2006 Lennox industries Inc.

Dallas, Texas, USA

INSTALLATION

INSTRUCTIONS

G50UH(X) Series

GAS FURNACE

505,254M _ Technical

8/2006 .L_._L Publications

Supersedes 504,957M Lithe U.S.A.

RETAIN THESE INSTRUCTIONS

FOR FUTURE REFERENCE

Unit Dimensions ................................ 2

G50UH(X) Parts Arrangement .................... 3

G50UH(X) Gas Furnace .......................... 4

Shipping and Packing List ........................ 4

Safety Information ............................... 4

General ........................................ 5

Combustion, Dilution & Ventilation Air .............. 6

Setting Equipment ............................... 8

Filters .......................................... 12

Duct System .................................... 12

Venting ........................................ 12

Gas Piping ..................................... 20

Electrical ....................................... 21

Unit Start-Up ................................... 25

Gas Pressure Adjustment ........................ 26

High Altitude Information ......................... 27

Other Unit Adjustments .......................... 27

Service ........................................ 28

Repair Parts List ................................ 30

Ignition Control Board Diagnostic Codes ........... 30

Troubleshooting ................................. 31

Start-Up & Performance Check List ................ 35

&WARNING

Do not store or use gasoline or other

flammable vapors and liquids in the

vicinity of this or any other ap-

pliance.

Installation and service must be

performed by a qualified installer,

service agency or the gas supplier.

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.

•Leave the building immediately.

•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.

08/06

IIIHIININIIIIIIIIIIIIIIIIIIIIIIIIIIII Page1

505,254M

IIIHIIIIIIIIIIIIIIIIIIINIIIIIIIIIIIIIIIIIIIIIII

1 NOTE -60C and 60D size units that require air volumes

over 1800 cfm (850 L/s) must have one of the following:

1. Single side return air with transition, to accommodate

20 x 25 x 1 in. (508 x 635 x 25 mm) air filter. Required to

maintain proper air velocity across the filter.

2. Single side return air with optional RAB Return Air Base

3. Bottom return air.

4. Return air from both sides.

5. Bottom and one side return air.

See Blower Performance Tables for additional information.

3-3/4 (95)-I_ 1

FLUE OUTLET

(Top)

SUPPLY AIR

OPENING

2 Flue outlet may be horizontal but furnace must be

vented vertically

3 Optional External Side Return Air Filter Kit is not for use

with the optional RAB Return Air Base.

1OPTIONAL

EXTERNAL

SIDE RETURN

AIR FILTER KIT

(Either Side)

23-3/4 (603)

I_1 25 (635) =

TOP VIEW

I I

/" ........... h r........... h::::::::h f..............

,_ A -_

B_ 4-9/16 (14)

3 OPTIONAL

EXTERNAL

SIDE RETURN

AIR FILTER KIT

__ (Either Side)

__ 40

.... (1016)

,, i

AiR FLOW !1

5/8 (16)

1Bottom Return

Air Opening

FRONT VIEW

3-1/4 (83) Right

8-1/8 (206) Left

13-1/4 (337) Left

4-7/8 (124) Right

2-1/4 (57) Left -I_

TOP VIEW 28-1/2

(724)

r--

4-1/4

(108)

iE OUTLET

(Either Side)

ELECTRICAL INLET

(Either Side)

oGAS PIPING INLET

(Either Side)

ELECTRICAL INLET

OW (Either Side)

4 23

[102 (584) 14

1OPTIONAL

RETURN CUTOUT (3_6)

L(Either Side)

1-15/16 (49)

23-1/2 v

(597)

1 Bottom Return

Air Opening

SIDE VIEW

ABCD

Model No. in. mm in. mm in. mm in. mm

G50UH-24A-045,

G50UH-24A-070, 14-1/2 368 13-3/8 340 13 330 4-1/2 114

G50UH-36A-070

G50UH-36B-090, 17-1/2 446 16-3/8 416 16 406 6 152

G50UH-48B-090

G50UH-36C-110,

G50UH-48C-110, 21 533 19-7/8 504 19-1/2 495 7-3/4 197

G50UH-48C-135,

G50UH-60C-110

G50UH-60D-135, 24-1/2 622 23-3/8 546 23 584 9-1/2 241

G50UH-60D-155

9/16

Page 2

Gasket

FlueBoxGasket

HeatExchanger

FlueCollectorBox

AirDeflector

G50UH-48C-135,

G50UH-60C-110&

G50UH-60D-155

UnitsOnly

FlueTransition

Flame Sensor _

Flame Rollout Switches*

Flame Rollout Bracket

Gas Valve

Gas Orifices

Ignitor Bracket Ig'_itor

Combustion Air

Orifice

Combustion Air

Pressure Switch

Air Inducer

Limit Shield

Primary Limit

NOx Insert

(NO x Units Only)

Secondary Limit

Burner Bottom Shield

Control Transformer

_ _'_ X Blower Assembly

SureLight ¢ Control Board _'_ " Capacitor

"135 and 155 kBtuh units only --

Flame rollout switches are located

on brackets on the inner sides (one _ Door Interlock Switch

on the left and one on the right) of

the burner box.

FIGURE 1

Page 3

TheG50UH(X)gasfurnaceisshippedreadyforinstalla-

tionintheupfioworhorizontalposition(leftorright).The

furnaceisshippedwiththebottompanelinplace.Thebot-

tompanelmustberemovediftheunitistobeinstalledina

horizontalapplication.Thepanelmayalsoberemovedin

upfiowapplications.

Package 1 of 1 contains

1 - Assembled G50UH(X) unit

1 - Bag assembly containing the following:

2 - Screws

3 -Wire nuts

1 - Snap bushing

1 - Snap plug

1 - Wire tie

1 -Vent warning label

1 - Owner's manual and warranty card

The following items may be ordered separately:

1- Thermostat

1 - Hanging bracket (for horizontal installations)

1 - Propane/LP changeover kit

1 - High altitude kit

1 - Return air base

1 - Side filter kit

Check equipment for shipping damage, If you find any

damage, immediately contact the last carrier.

A,WARNING

A,CAUTION

G50UH(X) units are CSA International certified to ANSI

Z21.47 and CSA 2.3 standard.

In the USA, installation of gas furnaces must conform with

local building codes. In the absence of local codes, units

must be installed according to the current National Fuel

Gas Code (ANSI-Z223.1/NFPA 54). The National Fuel Gas

Code is available from the following address:

American National Standards Institute, Inc.

11 West 42nd Street

New York, NY 10036

In Canada, installation must conform with current National

Standard of Canada CSA B149 Natural Gas and Propane

Installation Codes," local plumbing or waste water codes

and other applicable local codes.

Adequate clearance must be made around the air open-

ings into the vestibule area. In order to ensure proper unit

operation, combustion and ventilation air supply must be

provided according to the current National Fuel Gas Code

or CSA B149 standards.

Vent installations must be consistent with the venting

tables (in this instruction) and applicable provisions of local

building codes.

This furnace is CSA Intemational certified for installation

clearances to combustible material as listed on the unit

nameplate and in the tables in figures 6 and 11. Accessibility

and service clearances must take precedence over fire

protection clearances.

NOTE- For installation on combustible floors, the furnace

shaft not be installed directly on carpeting, tile, or other

combustible material other than wood flooring.

For installation in a residential garage, the furnace must

be installed so that the burner(s) and the ignition source

are located no less than 18 inches (457 mm) above the

floor. The furnace must be located or protected to avoid

physical damage by vehicles. When a furnace is installed

in a public garage, hangar, or other building that has a haz-

ardous atmosphere, the furnace must be installed accord-

ing to recommended good practice requirements and cur-

rent National Fuel Gas Code or CSA B149 standards.

NOTE -Furnace must be adjusted to obtain a temperature

rise within the range specified on the unit nameplate. Failure

to do so may cause erratic limit operation.

This G50UH(X) furnace must be installed so that its electri-

cal components are protected from water.

When this furnace is used with cooling units, it shall be

installed in parallel with, or on the upstream side of, cooling

units to avoid condensation in the heating compartment.

With a parallel flow arrangement, a damper (or other

means to control the flow of air) must adequately prevent

chilled air from entering the furnace. If the damper is manu-

ally operated, it must be equipped to prevent operation of

either the heating or the cooling unit, unless it is in the full

HEAT or COOL setting.

Page 4

Wheninstalled,thisfurnacemustbeelectricallygrounded

accordingtolocalcodes.Inaddition,intheUnitedStates,

installationmustconformwiththecurrentNationalElec-

tricCode,ANSI/NFPANo.70.TheNationalElectricCode

(ANSI/NFPANo.70)isavailablefromthefollowingad-

dress:

NationalFireProtectionAssociation

1BatteryMarchPark

Quincy,MA02269

InCanada,allelectricalwiringandgroundingfortheunit

mustbeinstalledaccordingtothecurrentregulationsofthe

CanadianElectricalCodePartI (CSAStandardC22.1)

and/orlocalcodes.

NOTE -This furnace is designed for a minimum continu-

ous return air temperature of 60°F (16°C) or an intermit-

tent operation down to 55°F (13°C) dry bulb for cases

where a night setback thermostat is used. Return air tem-

perature must not exceed 85°F (29 °C) dry bulb.

The G50UH(X) furnace may be installed in alcoves, clos-

ets, attics, basements, garages, and utility rooms in the up-

flow or horizontal position.

This furnace design has not been CSA International certi-

fied for installation in mobile homes, recreational vehicles,

or outdoors.

Lennox does not recommend the use of G50UH units as a

construction heater during any phase of construction. Very

low return air temperatures, harmful vapors and operation

of the unit with clogged or misplaced filters will damage the

unit.

G50UH units may be used for heating of buildings or struc-

tures under construction, if the following conditions are

met:

•The vent system must be permanently installed per

these installation instructions.

• A room thermostat must control the furnace. The use of

fixed jumpers that will provide continuous heating is not

allowed.

• The return air duct must be provided and sealed to the

furnace.

• Return air temperature range between 60°F (16°C) and

80°F (27°C) must be maintained.

• Air filters must be installed in the system and must be

maintained during construction.

• Air filters must be replaced upon construction comple-

tion.

• The input rate and temperature rise must be set per the

furnace rating plate.

• One hundred percent (100%) outdoor air must be pro-

vided for combustion air requirements during construc-

tion. Temporary ducting may supply outdoor air to the

furnace. Do not connect duct directly to the furnace.

Size the temporary duct following these instructions in

section for Combustion, Dilution and Ventilation Air in a

confined space with air from outside.

• The furnace heat exchanger, components, duct system,

air filters and evaporator coils must be thoroughly

cleaned following final construction clean-up.

• All furnace operating conditions (including ignition, in-

put rate, temperature rise and venting) must be verified

according to these installation instructions.

NOTE -The Commonwealth of Massachusetts stipu-

lates these additional requirements:

• Gas furnaces shall be installed by aticensedptumb-

er or gas fitter only.

• The gas cock must be "T handle" type.

• When afurnace is installed in an attic, the passage-

way to and service area surrounding the equipment

shall be floored.

These instructions are intended as a general guide and do

not supersede local codes in any way. Consult authorities

having jurisdiction before installation.

In addition to the requirements outlined previously, the fol-

lowing general recommendations must be considered

when installing a G50UH(X) furnace:

•Place the furnace as close to the center of the air dis-

tribution system as possible. The furnace should also be

located close to the chimney or vent termination point.

•Do not install the furnace where drafts might blow direct-

ly into it. This could cause improper combustion and un-

safe operation.

•Do not block the furnace combustion air openings with

clothing, boxes, doors, etc. Air is needed for proper

combustion and safe unit operation.

•When the furnace is installed in an attic or other insu-

lated space, keep insulation away from the furnace.

WARNING

Page 5

Inthepast,therewasnoprobleminbringinginsufficientout-

doorairforcombustion.Infiltrationprovidedalltheairthat

wasneeded.Intoday'shomes,tightconstructionpractices

makeit necessaryto bringinairfromoutsideforcombus-

tion.Takeintoaccountthatexhaustfans,appliancevents,

chimneys,andfireplacesforceadditionalairthatcouldbe

usedforcombustionoutofthehouse.Unlessoutsideairis

broughtintothehousefor combustion,negativepressure

(outsidepressureisgreaterthaninsidepressure)willbuild

tothepointthatadowndraftcanoccurinthefurnacevent

pipeorchimney.Asaresult,combustiongasesentertheliv-

ingspacecreatinga potentiallydangeroussituation.

Intheabsenceoflocalcodesconcerningairforcombus-

tionandventilation,usetheguidelinesandproceduresin

thissectiontoinstallG50UH(X)furnacestoensureefficient

andsafeoperation.Youmustconsidercombustionair

needsandrequirementsforexhaustventsandgaspiping.

A portionof thisinformationhasbeenreprintedwithper-

missionfromtheNationalFuelGasCode(ANSI-Z223.1).

Thisreprintedmaterialisnotthecompleteandofficialposi-

tionoftheANSIonthereferencedsubject,whichisrepre-

sentedonlybythestandardinitsentirety.

In Canada,referto the standardCSAB149installation

codes.

ACAUTION

All gas-fired appliances require air for the combustion pro-

cess. If sufficient combustion air is not available, the fur-

nace or other appliances will operate inefficiently and un-

safely. Enough air must be provided to meet the needs of all

fuel-burning appliances and appliances such as exhaust

fans which force air out of the house. When fireplaces, ex-

haust fans, or clothes dryers are used at the same time as

the furnace, much more air is necessary to ensure proper

combustion and to prevent a downdraft. Insufficient air

causes incomplete combustion which can result in carbon

monoxide,

In addition to providing combustion air, fresh outdoor air

dilutes contaminants in the indoor air. These contami-

nants may include bleaches, adhesives, detergents, sol-

vents and other contaminants which can corrode furnace

components,

The requirements for providing air for combustion and ven-

tilation depend largely on whether the furnace is installed in

an unconfined or a confined space,

Unconfined Space

An unconfined space is an area such as a basement or

large equipment room with a volume greater than 50 cubic

feet (1.42 m3) per 1,000 Btu (.29 kW) per hour of the com-

bined input rating of all appliances installed in that space.

This space also includes adjacent rooms which are not

separated by a door. Though an area may appear to be un-

confined, it might be necessary to bring in outdoor air for

combustion if the structure does not provide enough air by

infiltration. If the furnace is located in a building of tight

construction with weather stripping and caulking around

the windows and doors, follow the procedures in the air

from outside section.

Confined Space

A confined space is an area with a volume less than 50 cu-

bic feet (1.42 m3) per 1,000 Btu (.29 kW) per hour of the

combined input rating of all appliances installed in that

space. This definition includes furnace closets or small

equipment rooms.

When the furnace is installed so that supply ducts carry air

circulated by the furnace to areas outside the space contain-

ing the furnace, the return air must be handled by ducts

which are sealed to the furnace casing and which terminate

outside the space containing the furnace, This is especially

important when the furnace is mounted on a platform in a

confined space such as a closet or small equipment room.

Even a small leak around the base of the unit at the platform

or at the return air duct connection can cause a potentially

dangerous negative pressure condition, Air for combustion

and ventilation can be brought into the confined space either

from inside the building or from outside,

Page 6

CHIMNEY

VENT

EQUIPMENT IN CONFINED

SPACE ALL AIR FROM INSIDE

WiTER/

HEATER

FURNACE 1_

OPENINGS

(To Adjacent

Room)

I I I I

NOTE -Each opening shall have afree area of at least one square

inch (645 mm 2) per 1,000 Btu (.29 kW) per hour of the total input rat-

ing of all equipment in the enclosure, but not less than 100 square

inches (64516 mm2).

FIGURE 2

Air from Inside

If the confined space that houses the furnace adjoins a

space categorized as unconfined, air can be brought in by

providing two permanent openings between the two

spaces. Each opening must have a minimum free area of 1

square inch (645 mm2) per 1,000 Btu (.29 kW) per hour of

total input rating of all gas-fired equipment in the confined

space. Each opening must be at least 100 square inches

(64516 mm2). One opening shall be within 12 inches (305

mm) of the top of the enclosure and one opening within 12

inches (305 mm) of the bottom. See figure 2.

Air from Outside

If air from outside is brought in for combustion and ventila-

tion, the confined space must have two permanent open-

ings. One opening shall be within 12 inches (305 mm) of the

top of the enclosure and one opening within 12 inches (305

mm) of the bottom. These openings must communicate di-

rectly or by ducts with the outdoors or spaces (crawl or at-

tic) that freely communicate with the outdoors or indirectly

through vertical ducts. Each opening shall have a minimum

free area of 1 square inch (645 mm2) per 4,000 Btu (1.17

kW) per hour of total input rating of all equipment in the en-

closure. See figures 3 and 4. When communicating with

the outdoors through horizontal ducts, each opening shall

have a minimum free area of 1 square inch (645 mm 2) per

2,000 Btu (.56 kW) per total input rating of all equipment in

the enclosure. See figure 5.

When ducts are used, they shall be of the same cross-sec-

tional area as the free area of the openings to which they

connect. The minimum dimension of rectangular air ducts

shall be no less than 3 inches (75 mm). In calculating free

area, the blocking effect of louvers, grilles, or screens must

be considered. Ifthe design and free area of protective cov-

ering is not known for calculating the size opening required,

it may be assumed that wood louvers will have 20 to 25 per-

cent free area and metal louvers and grilles will have 60 to

75 percent free area. Louvers and grilles must be fixed in the

open position or interlocked with the equipment so that they

are opened automatically during equipment operation.

CHIMNEY OR

GAS VENT

EQUIPMENT IN CONFINED SPACE

ALL AIR FROM OUTSIDE

(Inlet Air from Crawlspace and Outlet Air

to Ventilated Attic)

VENTILATION LOUVERS

(Each end of attic)

I ...... I

OUTLET

FURNACE AIR WATER

HEATER

VENTILATION INLET

LOUVERS AIR

(For unheated crawl !

NO TE- The inlet and outlet air openings shall each have a free area of at least one square inch (645

mm 2) per 4, 000 Btu (1.17 kW) per hour of the total input rating of all equipment in the enclosure.

FIGURE 3

Page 7

CHIMNEY

OR GAS

VENT_

EQUIPMENT IN CONFINED SPACE

ALL AIR FROM OUTSIDE

(All Air Through Ventilated Attic)

VENTILATION LOUVERS

(Each end of attic)

FURNACE INLET AIR

(Ends 12 in.

above bottom)

HEATER

NO TE- The inlet and outlet air openings shall each have a

free area of at least one square inch (645 mm 2)per 4,000

Btu (1.17 kW) per hour of the total input rating of all equip-

ment in the enclosure.

FIGURE 4

A _ EQUIPMENT IN

TT'_. JJ_ CONFINED SPACE

I I "_'Y _ ALLAIRFROM

I 1 OUTLET AIR

FURNACE

I1"- ,,

I ii I I I I I I I I I I I

NOTE -Each air duct opening shall have a free area of at least

o 2

ne square inch (645 mm Jper 2, 000 Btu (.59 kW) per hour of

the total input rating of all equipment in the enclosure. If the

equipment room is located against an outside wall and the air

openings communicate directly with the outdoors, each open-

ing shall have a free area of at least one square inch (645 mm 2)

per4,000 Btu (1.17 kW) per hour of the total input rating of all

other equipment in the enclosure.

FIGURE 5

-&WARNING

The G50UH(X) gas furnace can be installed as shipped

in either the upfiow position or the horizontal position,

with right-hand or left-hand air discharge.

Select a location that allows for the required clearances

that are listed on the unit nameplate. Also consider gas

supply connections, electrical supply, vent connection,

and installation and service clearances [24 inches (610

mm) at unit front]. The unit must be level.

NOTE -1/3 hp blower motors are equipped with four flex-

ible mounting legs. 1/2 hp blower motors are equipped with

three flexible legs and one rigid leg. The rigid leg is

equipped with a shipping bolt and a flat white plastic wash-

er (rather than the rubber mounting grommet used with a

flexible mounting leg). The bolt and washer must be re-

moved before the furnace is placed into operation. Af-

ter the bolt and washer have been removed, the rigid leg

will not touch the blower housing.

Upflow Applications

Allow for clearances to combustible materials as indicated

on the unit nameplate. Minimum clearances for closet or al-

cove installations are shown in figure 6.

Upflow Application Installation Clearances

Top

Left Side Right Side

Type of Vent

Connector

Top

*Front

Back

Sides

Vent

Floor

Bottom

Type C

1 in, (25 ram)

3in, (76 ram)

6 in. (152 ram)

Type B1

1in, (25 ram)

3in, (76 ram)

1in. (25 ram)

0J;

*Front clearance in alcove installation must be 24 in. (610 ram).

Maintain a minimum of 24 in. (610 ram) for front service access.

SFor installation on a combustible floor, do not install the furnace

directly on carpeting, tile or other combustible materials other

than wood flooring.

l-Left side requires 3 inches ifa single wall vent is used on 14-1/2

inch cabinets, or 2 inches if a single wall vent is used on 17-1/2

inch cabinets.

FIGURE 6

Page 8

Return Air -- Upflow Applications

Return air can be brought in through the bottom or either

side of the furnace installed in an upflow application. If the

furnace is installed on a platform with bottom return, make

an airtight seal between the bottom of the furnace and the

platform to ensure that the furnace operates properly and

safely. The furnace is equipped with a removable bottom

panel to facilitate installation,

Markings are provided on both sides of the furnace cabinet

for installations that require side return air. Cut the furnace

cabinet at the maximum dimensions shown on page 2.

NOTE -When air volumes over 1800 cfm (850 L/s) are

required with 60C or 60D models in an upflow applica-

tion, the following return air options are available:

1-Return air from single side with transition which will

accommodate 20 x 25 x 1 in. (508 x 635 x 25 mm) clean-

able air filter. (Required to maintain proper air velocity.)

See figure 7.

2 - Return air from single side with optional RAB Return

Air Base. See figure 8.

3-Return air from bottom.

4-Return air from both sides.

5-Return air from bottom and one side.

Refer to Engineering Handbook for additional information.

Side Return Air

(with transition and filter)

Transition

FIGURE 7

Optional Return Air Base

(Upflow Applications Only -- For use with B, Cand D cabinets only)

20" X 25" X 1"

(508mm X635mm X 25mm)

Cleanable Filter

Return Air

Plenum

AIR FLOW

7-1/4 (184)

17-1/2 (446) RAB-B (98M60)

21 (533) RAB-C (98M58)

24-1/2 (622) RAB-D (98M59)

FRONT VIEW

OPTIONAL RAB

RETURN AIR BASE 7/8

(22)

(102)1"9_- 123(584) fL_-

Overall 1 MinimuV_

(Maximum) 11 (279)

2 Maximurr

1 Unit side return airOpening 11_5.6) j_ __

5-5/8

(143)

....................._ 23 (584)........................................................................_!

_1-- 27-5/8 (702)

SIDE VIEW

122-7-16

(570)

Overall

Maximum)

_-- 3/4

(19)

NOTE- Optional Side Return Air Filter Kits are not for use with RAB Return Air Base.

1 Both the unit return air opening and the base return air opening must be covered by a single plenum or IAQ cabinet.

Minimum unit side return air opening dimensions for units requiring 1800 cfm or more of air (W x H): 23 x 11 in.

(584 x 279 mm).

The opening can be cut as needed to accommodate plenum or IAQ cabinet while maintaining dimensions shown.

Side return air openings must be cut in the field. There are cutting guides stenciled on the cabinet for the side return

air opening. The size of the opening must not extend beyond the markings on the furnace cabinet..

2 To minimize pressure drop, the largest opening height possible (up to 14 inches) is preferred.

NOTE- Optional Side Return Air Filter Kits are not for use with RAB Return Air Base.

FIGURE 8

Page 9

Removingthe Bottom Panel

Remove the two screws that secure the bottom cap to the

furnace. Pivot the bottom cap down to release the bottom

panel. Once the bottom panel has been removed, reinstall

the bottom cap, See figure 9.

Removing the Bottom Panel

Screw

Bottom Cap

Bottom

FIGURE 9

Leveling an Upflow Unit

When the side return air inlets are used in an upflow ap-

plication, it may be necessary to install leveling bolts on the

bottom of the furnace. Use field-supplied corrosion-resist-

ant 5/16 inch machine bolts (4) and nuts (8), See figure 10.

NOTE -The maximum length of the bolt is 1-1/2 inches.

1 - Lie the furnace on its back and drill a 5/16 inch diame-

ter hole in each corner of the furnace's bottom. See fig-

ure 10 for the correct location of the holes, Drill through

the bottom panel and the bottom flange of the cabinet,

2 - Install one bolt and two nuts into each hole. Screw the

first nut onto a bolt and then insert the bolt into a hole, A

fiat washer may be added between the nut and the bot-

tom of the unit,

3 - Screw another nut onto the bolt on the inside of the fur-

nace base. A flat washer may be added between the

nut and the bottom of the unit,

4 - Adjust the outside nut to the appropriate height and

tighten the inside nut to secure the arrangement,

Leveling Bolt Installation

Inches (mm)

3/8

(10)_r

Furnace Front _'1 [

3/8 1-3/4

(44)

1-3/4

(44)

Leveling Bolt

Locati_

3/8

(10)

I-3/4 (44)

Furnace

Bottom

Leveling Bolt

Locations

3/8

(10)

1-3/4

(44)

FIGURE 10

Horizontal Applications

The G50UH(X) furnace can be installed in horizontal ap-

plications,

Allow for clearances to combustible materials as indicated

on the unit nameplate, Minimum clearances for closet or al-

cove installations are shown in figure 11,

Horizontal Application

Installation Clearances

Top

Left End Right End

Vent Connector

Type

Top

*Front

Back

Ends

Vent

Floor

Bottom

Type C

3in. (76 ram)

2in. (51 ram)

6in. (152 ram)

o:_

Type B1

3in. (76 ram)

2in. (51 ram)

1in. (25 ram)

o:_

*Front clearance in alcove installation must be 24 in. (610 ram).

Maintain a minimum of 24 in. (610 ram) for front service access.

_:For installations on a combustible floor, do not install the furnace

directly on carpeting, tile or other combustible materials other

than wood flooring.

FIGURE 11

Page 10

Thisfurnacemaybeinstalledineitheranatticoracrawl-

space.Eithersuspendthefurnacefromroofraftersor

floorjoists,asshowninfigure12,orinstallthefurnaceon

a platform,asshownin figure13.Theunitmustbesup-

portedat bothendsandbeneaththeblowerdecktopre-

ventsagging.

Typical Horizontal Application

Unit Suspended in Attic or Crawlspace

Leave sufficient clearance between rod and unit to

remove access panel.

1/4 i

ANGLE

IRON U-CHANNELS

FIGURE 12

NOTE -Heavy-gauge perforated sheet metal straps

(plumbers' straps) may be used to suspend the unit from

roof rafters or ceiling joists. When straps are used to sus-

pend the unit in this way, support must be providedfor both

the ends and the middle of the furnace to prevent sagging.

The straps must not interfere with the plenum or exhaust

piping instaflation. Securing screws should be 1/2 inch

from the top edge and 1-1/2 inch from the side edge in aft

cases. Cooling coils and supply and return air plenums

must be supported separately.

NOTE -When the furnace is installed on a platform in a

crawlspace, it must be elevated enough to avoid water

damage and to allow the evaporator coil to drain.

Return Air -- Horizontal Applications

Return air can be brought in through the end of a furnace

installed in a horizontal application, The furnace is

equipped with a removable bottom panel to facilitate

installation, See figure 9,

Horizontal Application

Unit Installed on Platform

NOTE -Line contact is permis-

sible. See the unit nameplate for

clearances.

\\\

GAS

ENTRY

__VENT

PIPE

WORKING

PLATFORM

FIGURE 13

-&WARNING

&WARNING

Page 11

Thisunitisnotequippedwithafilteror rack.A field-pro-

videdhigh-velocityfilterisrequiredfortheunittooperate

properly.Table1listsrecommendedfiltersizes.

Afiltermustbein placeanytimetheunitisoperating.

Furnace

Cabinet Size

14-1/2"

17-112"

21"

24-1/2"

TABLE 1

Filter Size

Side Return

16X25X 1 (1)

16 X 25 X 1 (2)

Bottom Return

14X25X1 (1)

16X25X1 (1)

20X25X 1 (1)

24X25X 1 (1)

Use industry-approved standards to size and install the

supply and return air duct system. This will result in a quiet

and low-static system that has uniform air distribution.

NOTE -Do not operate the furnace with an external static

pressure that exceeds 0,5 inches w,c, Higher external stat-

ic pressures may cause erratic limit operation,

Supply Air Plenum

If the furnace is installed without a cooling coil, a removable

access panel must be installed in the supply air duct, The

access panel should be large enough to permit inspection

(either by smoke or reflected light) of the heat exchanger

for leaks after the furnace is installed, The furnace access

panel must always be in place when the furnace is operat-

ing and it must not allow leaks into the supply air duct sys-

tem,

Return Air Plenum

Return air must not be drawn from aroom where this

furnace, or any other gas appliance (ie., a water heat-

er), is installed. When return air is drawn from a room, a

negative pressure is created in the room, If a gas ap-

pliance is operating in a room with negative pressure, the

flue products can be pulled back down the vent pipe and

into the room, This reverse flow of the flue gas may result

in incomplete combustion and the formation of carbon

monoxide gas. This toxic gas might then be distributed

throughout the house by the furnace duct system,

In upflow applications, the return air can be brought in

through the bottom or either side of the furnace. If a fur-

nace with bottom return air is installed on a platform, make

an airtight seal between the bottom of the furnace and the

platform to ensure that the unit operates properly and

safely, Use fiberglass sealing strips, caulking, or equiva-

lent sealing method between the plenum and the furnace

cabinet to ensure a tight seal, Ifa filter is installed, size the

return air duct to fit the filter frame.

A 4-inch diameter flue transition is factory-installed on the

combustion air inducer outlet of all models. Modifying or

removing the flue transition will cause the unit to oper-

ate unsafely and will void the unit certification. The

vent connector does not require insulation.

The combustion air inducer may be rotated clockwise or

counterclockwise by 90° to allow for top or side vent dis-

charge in all applications. When the unit is installed, the flue

transition must be in the 9 o'clock, 12 o'clock or 3 o'clock

position. The unit will not vent properly with the flue

transition pointed down in the 6 o'clock position. Re-

move the four mounting screws, rotate the assembly (in-

cluding the gasket), then reinstall the mounting screws.

See figure 14. Use the provided wire tie to bundle the pres-

sure switch wires with the inducer motor power leads.

Route the wires away from moving parts and the heat

of the inducer motor to prevent damage to the wires.

Combustion Air Inducer

Flue Transition

(Do not remove)

Mounting Screws

(Remove)

FIGURE 14

Power Leads

Optional Flue Outlet

(Horizontal Installation)

Top View of Furnace

Top Cap ----__ _

Flue Outlet _<_J

Hole /

(Reattach II 111

Cutout Here)

Supply Air

Opening

Optional

Flue Outlet

FIGURE 15

Page 12

Usesheetmetalshearstoremovethecutoutfromtheside

ofthecabinet.Usethetwoprovidedsheetmetalscrewsto

installthecutoutonthetopcaptocovertheoriginalflue

outletopening.Seefigure15.

TheG50UH(X)seriesunitsareclassifiedasfan-assisted

CategoryIfurnaceswhenverticallyventedaccordingto

thelatesteditionof NationalFuelGasCode(NFPA54/

ANSI Z223.1 ) in the USA and the current standards of CSA

B149 Natural Gas and Propane Installation Codes in Can-

ada. A fan-assisted Category I furnace is an appliance

equipped with an integral mechanical means to either draw

or force combustion products through the combustion

chamber and/or heat exchanger.

NOTE -Use these instructions as a guide. They do not su-

persede local codes. This furnace must be vented accord-

ing to all local codes these installation instructions, and the

provided venting tables in these instructions

The venting tables in this manual were extracted from the

National Fuel Gas Code (NFPA 54 /ANSI Z223.1 ) and are

provided as a guide for proper vent installation. Proper ap-

plication, termination, construction and location of vents

must conform to local codes having jurisdiction. In the ab-

sence dlocal codes, the NFGC serves as the defining doc-

ument.

Refer to the tables and the venting information contained in

these instructions to properly size and install the venting

system.

klMPORTANT

kWARNING

VENT CONNECTION

VENT

PIPE

FURNACE

FLUE TRANSITIOF

COLLAR

FIGURE 16

Use self-drilling sheet metal screws or a mechanical fas-

tener to firmly secure the vent pipe to the round collar of the

flue transition. If self-drilling screws are used to attach the

vent pipe, it is recommended that three be used. Drive one

self-drilling screw through the front and one through each

side of the vent pipe and collar. See figure 16.

Install the first vent connector elbow at a minimum of six

inches (152 mm) from the furnace vent outlet.

Venting Using a Masonry Chimney

The following additional requirements apply when a lined

masonry chimney is used to vent this furnace.

Masonry chimneys used to vent Category I central fur-

naces must be either tile-lined or lined with a listed metal

lining system or dedicated gas vent. Unlined masonry

chimneys are prohibited. See figures 17 and 18 for com-

mon venting.

A chimney with one or more sides exposed to the outside of

the structure is considered to be an exterior chimney.

An exterior masonry chimney that is not tile-lined must be

lined with B1 vent or a listed insulated flexible metal vent.

An exterior tileqined chimney that is sealed and capped

may be lined with a listed uninsulated flexible metal vent.

If the existing chimney will not accommodate a B1 vent or

an insulated flexible vent pipe liner, either the chimney

must be rebuilt to accommodate one of these liners or an

alternate approved venting method must be found.

Insulation for the flexible vent pipe must be an encapsu-

lated fiberglass sleeve recommended by the flexible vent

pipe manufacturer. See figure 17.

G50UH units installed in upflow applications may be

vented into a tile-lined masonry chimney without using a

listed metal liner, provided that the optional masonry chim-

ney vent adapter kit (18M79) is used. Instructions provided

with the kit must be followed exactly.

DO NOT insulate the space between the liner and the

chimney wall with puffed mica or any other loose gran-

ular insulating material

CommonVenting Using Metal-Lined Masonry Chimney

T MAX. LENGTH

-- SEE NOTE 1

BELOW.

VE%OO.o%OTOR "

SEALED

II EXTERIOR

CHIMNEY WITH

II METAL

II LINER

__ .,J

PERMANENTLY

SEALED FIREPLACE

OPENING

NOTE 1 -Refer to the provided venting tables for installations in the USA

and the venting tables in CSA B149 for installations Canada.

NOTE 2 -Either single-walled or double-walled vent connector may be

used. Refer to the capacity requirements shown in the provided venting

tables for installations in USA and the venting tames in current CSA

B149 for installations in Canada.

FIGURE 17

Page 13

Common Venting Using Tile-Lined Interior Masonry Chimne

MINIMUM LENGTH = AS SHORT AS PRACTICAL.

FOR MAXIMUM LENGTH SEE NOTE TO LEFT

NOTE- Refer to provided venting tables

for installations in the USA and the

venting tables in current CSA B149 for

installations in Canada. _

OTHER

APPLIANCE

_Row

'and Combined Vent Connector

INTERIOR TILE=LINED

MASONRY CHIMNEY

NOTE -the chimney must be properly

sized per provided venting tables or

lined with listed metal lining system.

PERMANENTLY

SEALED FIREPLACE

OPENING

NOTE -Either single-walled or double-walled vent connector may be used. Refer to the capacity requirements as shown in the pro-

vided venting tables for installations in USA and the venting tables in current CSA B149 for installations in Canada.

,IMPORTANT

A fan-assisted furnace may be commonly vented into an

existing lined masonry chimney if the following conditions

are met:

• The chimney is currently serving at least one drafthood

equipped appliance

• The vent connectors and chimney are sized accord-

ing to the provided venting tables for the USA, and

the appropriate venting tables in the standards of

CSA B149 Natural Gas and Propane Installation

Codes in Canada.

If type B1 double-wall vent is used inside a chimney, no oth-

er appliance can be vented into the chimney. The outer wall

of type B1 vent pipe must not be exposed to flue products.

A type B1 vent or masonry chimney liner shall terminate

above the roof surface with a listed cap or a listed roof as-

sembly according to the terms of their respective listings

and the vent manufacturer's instructions.

When inspection reveals that an existing chimney is not

safe for the intended purpose, it shall be rebuilt to conform

to nationally recognized standards, lined or relined with

suitable materials, or replaced with a gas vent or chimney

suitable for venting G50UH(X) series units. The chimney

passageway must be checked periodically to ensure that it

is clear and free of obstructions.

Do not install a manual damper, barometric draft regulator,

or flue restrictor between the furnace and the chimney.

FIGURE 18

Never connect a Category I appliance to a chimney that is

servicing a solid-fuel appliance. If a fireplace chimney flue

is used to vent this appliance, the fireplace opening must

be permanently sealed.

A type B or listed chimney lining system that passes

through an unused masonry chimney flue is not considered

to be exposed to the outdoors.

General Venting Requirements

Vent all G50UH(X) furnaces according to these instruc-

tions:

1 - Vent diameter recommendations and maximum allow-

able piping runs are found in the provided venting tables

for the USA, and the appropriate venting tables in the

standards of CSA B149 Natural Gas and Propane

Installation Codes for Canada.

2 - In no case should the vent or vent connector diameter

be less than the diameter specified in the provided

venting tables for the USA, and the appropriate venting

tables in the standards of CSA B149 Natural Gas and

Propane Installation Codes for Canada.

3 - Single appliance vents -If the vertical vent or tile-lined

chimney has a larger diameter or flow area than the

vent connector, use the vertical vent diameter to de-

termine the minimum vent capacity and the vent

connector diameter to determine the maximum vent

capacity, The flow area of the vertical vent, however,

shall not exceed 7 times the flow area of the listed ap-

pliance categorized vent area, drafthood outlet area or

flue collar area unless designed according to approved

engineering methods.

4 - Multiple appliance vents - The flow area of the largest

section of vertical vent or chimney shall not exceed 7

times the smallest listed appliance categorized vent

area, drafthood outlet area orflue collar area unless de-

signed according to approved engineering methods.

Page 14

5 - Theentirelengthofsinglewallmetalventconnector

shallbe readilyaccessiblefor inspection,cleaning,

andreplacement.

6 - Singleapplianceventingconfigurationswithzerolat-

erallengths(tables3and4)areassumedto haveno

elbowsintheventsystem.Forallotherventconfigura-

tions,theventsystemisassumedtohavetwo90° el-

bows.Foreachadditional90°elboworequivalent(for

exampletwo45°elbowsequalone90°elbow)beyond

two,themaximumcapacitylistedintheventingtable

shouldbereducedby10%(0.90x maximumlistedca-

pacity).

7 - Thecommonventingtables(5,6,7,and8)weregen-

eratedusinga maximumhorizontalventconnector

lengthof 1-1/2feet(.46m)foreachinch(25mm)of

connectordiameterasfollows:

TABLE 2

Connector Diameter Maximum Horizontal

inches (mm) Connector Length feet (m)

3 (76) 4-1/2 (1.37)

4 (102) 6 (1.83)

5 (127) 7-1/2 (2.29)

6 (152) 9 (2.74)

7 (178) 10-1/2 (3.20)

_If the common vertical vent is offset, the maximum

common vent capacity listed in the common venting

tables should be reduced by 20%, the equivalent of two

90° elbows (0.80 x maximum common vent capacity).

The horizontal length of the offset shall not exceed

1-1/2 feet (.46 m) for each inch (25 mm) of common

vent diameter.

9 - The vent pipe should be as short as possible with the

least number of elbows and angles required to com-

plete the job. Route the vent connector to the vent us-

ing the shortest possible route.

10 - A vent connector shall be supported without any dips

or sags and shall slope a minimum of 1/4 inch (6.4 mm)

per linear foot (305 mm) of connector, back toward the

appliance.

11 - Vent connectors shall be firmly attached to the furnace

flue collar by self-drilling screws or other approved

means, except vent connectors of listed type B vent

material which shall be assembled according to the

manufacturer's instructions. Joints between sections

of single wall connector piping shall be fastened by

screws or other approved means.

12- When the vent connector used for Category I ap-

pliances must be located in or pass through a crawl-

space or other areas which may be cold, that portion of

the vent connector shall be constructed of listed

double-wall type B vent material or material having

equivalent insulation qualities.

13 - All venting pipe passing through floors, walls, and ceil-

ings must be installed with the listed clearance to com-

bustible materials and be fire stopped according to lo-

cal codes. In absence of local codes, refer to NFGC

(Z223.1).

14 - No portion of the venting system can extend into, or pass

through any circulation air duct or plenum.

15 - Vent connectors serving Category I appliances shall

not be connected to any portion of mechanical draft

systems operating under positive pressure such as

Category III or IV venting systems.

16 - If vent connectors are combined prior to entering the

common vent, the maximum common vent capacity

listed in the common venting tables must be reduced by

10%, the equivalent of one 90° elbow (0.90 x maximum

common vent capacity).

17 - The common vent diameter must always be at least as

large as the largest vent connector diameter.

18 - In no case, shall the vent connector be sized more than

two consecutive table size diameters over the size of

the draft hood outlet or flue collar outlet.

19 - Do not install a manual damper, barometric draft regu-

lator or flue restrictor between the furnace and the

chimney.

20 - When connecting this appliance to an existing dedi-

cated or common venting system, you must inspect the

venting system's general condition and look for signs

of corrosion. The existing vent pipe size must conform

to these instructions and the provided venting tables

for the USA, and the appropriate venting tables in the

standards of CSA B149 Natural Gas and Propane

Installation Codes for Canada. If the existing venting

system does not meet these requirements, it must be

resized.

Page 15

TABLE 3

Capacity of Type B Double-Wall Vents with Type B Double-Wall Connectors

Serving a Single Category I Appliance

Vent and Connector Diameter - D (inches)

Height Lateral 3 Inch 4 Inch 5 Inch 6 Inch

H L

(feet) (feet) Appliance Input Rating in Thousands of Btu Per Hour

MIN MAX MIN MAX MIN MAX MIN MAX

0 0 78 0 152 0 251 0 375

2 13 51 18 97 27 157 32 232

64 21 49 30 94 39 153 50 227

6 25 46 36 91 47 149 59 223

0 0 84 0 165 0 276 0 415

2 12 57 16 109 25 178 28 263

85 23 53 32 103 42 171 53 255

8 28 49 39 98 51 164 64 247

0 0 88 0 175 0 295 0 447

2 12 61 17 118 23 194 26 289

10 5 23 57 32 113 41 187 52 280

10 30 51 41 104 54 176 67 267

0 0 94 0 191 0 327 0 502

2 11 69 15 136 20 226 22 339

15 5 22 65 30 130 39 219 49 330

10 29 59 40 121 51 206 64 315

15 35 53 48 112 61 195 76 301

0 0 97 0 202 0 349 0 540

2 10 75 14 149 18 250 20 377

5 21 71 29 143 38 242 47 367

20 10 28 64 38 133 50 229 62 351

15 34 58 46 124 59 217 73 337

20 48 52 55 116 69 206 84 322

0 0 100 0 213 0 374 0 587

2 9 81 13 166 14 283 18 432

5 21 77 28 160 36 275 45 421

30 10 27 70 37 150 48 262 59 405

15 33 64 44 141 57 249 70 389

20 56 58 53 132 66 237 80 374

30 NR NR 73 113 88 214 104 346

NOTE -Single appliance venting configurations withzero lateral lengths are assumed to have no elbows in the vent system. For all other

vent configurations, the vent system is assumed to have two 90°elbows. For each additional 90°elbow or equivalent (for example two 45 °

elbows equal one 90 ° elbow) beyond two, the maximum capacity listed in the venting table should be reduced by 10 percent (0.90 x maxi-

mum listed capacity).

Page 16

TABLE 4

Capacity of Type B Double-Wall Vents with Single-Wall Metal Connectors

Serving a Single Category I Appliance

Vent and Connector Diameter -D (inches)

Height Lateral 3 Inch 4 Inch 5 Inch 6 Inch

H L

(feet) (feet) Appliance Input Rating in Thousands of Btu Per Hour

MIN MAX MIN MAX MIN MAX MIN MAX

0 38 77 59 151 85 249 126 373

2 39 51 60 96 85 156 123 231

64 NR NR 74 92 102 152 146 225

6 NR NR 83 89 114 147 163 220

0 37 83 58 164 83 273 123 412

2 39 56 59 108 83 176 121 261

85 NR NR 77 102 107 168 151 252

8 NR NR 90 95 122 161 175 243

0 37 87 57 174 82 293 120 444

2 39 61 59 117 82 193 119 287

10 5 52 56 76 111 105 185 148 277

10 NR NR 97 100 132 171 188 261

0 36 93 56 190 80 325 116 499

2 38 69 57 136 80 225 115 337

15 5 51 63 75 128 102 216 144 326

10 NR NR 95 116 128 201 182 308

15 NR NR NR NR 158 186 220 290

0 35 96 54 200 78 346 114 537

2 37 74 56 148 78 248 113 375

5 50 68 73 140 100 239 141 363

20 10 NR NR 93 129 125 223 177 344

15 NR NR NR NR 155 208 216 325

20 NR NR NR NR 186 192 254 306

0 34 99 53 211 76 372 110 584

2 37 80 55 164 76 281 109 429

5 49 74 72 157 98 271 136 417

30 10 NR NR 91 144 122 255 171 397

15 NR NR 115 131 151 239 208 377

20 NR NR NR NR 181 223 246 357

30 NR NR NR NR NR NR NR NR

NOTE -Single appliance venting configurations with zero lateral lengths are assumed to have no elbows in the vent system. For all other

vent configurations, the vent system is assumed to have two 90°elbows. For each additional 90°elbow or equivalent (for example two 45°

elbows equal one 90°elbow) beyond two, the maximum capacity listed in the venting table should be reduced by 10percent (0.90 x maxi-

mum listed capacity).

Page 17

TABLE 5

Vent Connector Capacity

Type B Double-Wall Vents with Type B Double-Wall Connectors

Serving Two or More Category I Appliances

Vent and Connector Diameter - D (inches)

Vent Connector

Height Rise 3 Inch 4 Inch 5 Inch 6 Inch

H R Appliance Input Rating in Thousands of Btu Per Hour

(feet) (feet) MIN MAX MIN MAX MIN MAX MIN MAX

1 22 37 35 66 46 106 58 164

6 2 23 41 37 75 48 121 60 183

3 24 44 38 81 49 132 62 199

1 22 40 35 72 49 114 64 176

8 2 23 44 36 80 51 128 66 195

3 24 47 37 87 53 139 67 210

1 22 43 34 78 49 123 65 189

10 2 23 47 36 86 51 136 67 206

3 24 50 37 92 52 146 69 220

1 21 50 33 89 47 142 64 220

15 2 22 53 35 96 49 153 66 235

3 24 55 36 102 51 163 68 248

1 21 54 33 99 46 157 62 246

20 2 22 57 34 105 48 167 64 259

3 23 60 35 110 50 176 66 271

1 20 62 31 113 45 181 60 288

30 2 21 64 33 118 47 190 62 299

3 22 66 34 123 48 198 64 309

TABLE 6

Common Vent Capacity

Type B Double-Wall Vents with Type B Double-Wall Connectors

Serving Two or More Category I Appliances

Common Vent Diameter -D (inches)

Vent

Height 4 Inch 5 Inch 6 Inch 7 Inch

H Appliance Input Rating in Thousands of Btu Per Hour

(feet) FAN + FAN FAN + NAT FAN + FAN FAN + NAT FAN + FAN FAN + NAT FAN + FAN FAN + NAT

6 92 81 140 116 204 161 309 248

8 101 90 155 129 224 178 339 275

10 110 97 169 141 243 194 367 299

15 125 112 195 164 283 228 427 352

20 136 123 215 183 314 255 475 394

30 152 138 244 210 361 297 547 459

Page 18

TABLE 7

Vent Connector Capacity

Type B Double-Wall Vents with Single-Wall Metal Connectors

Serving Two or More Category I Appliances

Vent and Connector Diameter - D (inches)

Vent Connector

Height Rise 3 Inch 4 Inch 5 Inch 6 Inch

H R Appliance Input Rating in Thousands of Btu Per Hour

(feet) (feet) MIN MAX MIN MAX MIN MAX MIN MAX

INR NR NR NR NR NR NR NR

6 2 NR NR NR NR NR NR 168 182

3 NR NR NR NR 121 131 174 198

1 NR NR 79 87 116 138 177 214

15 2 NR NR 83 94 121 150 185 230

3 NR NR 87 100 127 160 193 243

1 47 60 77 110 113 175 169 278

30 2 50 62 81 115 117 185 177 290

3 54 64 85 119 122 193 185 300

TABLE 8

Common Vent Capacity

Type B Double-Wall Vents with Single-Wall Metal Connectors

Serving Two or More Category I Appliances

Common Vent Diameter - D (inches)

Vent

Height 4 Inch 5 Inch 6 Inch 7 Inch

H Appliance Input Rating in Thousands of Btu Per Hour

(feet) FAN + FAN FAN + NAT FAN + FAN FAN + NAT FAN + FAN FAN + NAT FAN + FAN FAN + NAT

6 89 78 136 113 200 158 304 244

8 98 87 151 126 218 173 331 269

10 106 94 163 137 237 189 357 292

15 121 108 189 159 275 221 416 343

20 131 118 208 177 305 247 463 383

30 145 132 236 202 350 286 533 446

Removal of the Furnace from Common Vent

In the event that an existing furnace is removed from a

venting system commonly run with separate gas ap-

pliances, the venting system is likely to be too large to

properly vent the remaining attached appliances,

Conduct the following test while each appliance is operat-

ing and the other appliances (which are not operating) re-

main connected to the common venting system. If the

venting system has been installed improperly, you must

correct the system as indicated in the general venting re-

quirements section,

1 - Seal any unused openings in the common venting sys-

tem.

_Inspect the venting system for proper size and horizontal

pitch, Determine that there is no blockage, restriction,

leakage, corrosion, or other deficiencies which could

cause an unsafe condition,

3 - Close all building doors and windows and all doors be-

tween the space in which the appliances remaining

connected to the common venting system are located

and other spaces of the building. Turn on clothes dry-

ers and any appliances not connected to the common

venting system. Turn on any exhaust fans, such as

range hoods and bathroom exhausts, so they will oper-

ate at maximum speed. Do not operate a summer ex-

haust fan. Close fireplace dampers,

4 - Follow the lighting instructions, Turn on the appliance

that is being inspected. Adjust the thermostat so that

the appliance operates continuously,

5 - After the main burner has operated for 5 minutes, test

for leaks of flue gases at the draft hood relief opening,

Use the flame of a match or candle, or smoke from a

cigarette, cigar, or pipe,

6 - After determining that each appliance connected to the

common venting system is venting properly, (step 3)

return all doors, widows, exhaust fans, fireplace damp-

ers, and any other gas-burning appliances to their pre-

vious mode of operation,

7 - If a venting problem is found during any of the preced-

ing tests, the common venting system must be modi-

fied to correct the problem,

Page 19

Resizethecommonventingsystemto theminimum

ventpipesizedeterminedbyusingtheappropriate

tablesinappendixG.(Thesearein thecurrentstan-

dardsoftheNationalFuelGasCodeANSIZ223.1in

theUSA,andtheappropriateCategory1NaturalGas

andPropaneappliancesventingsizingtablesinthe

currentstandardsof theCSAB149NaturalGasand

PropaneInstallationCodesinCanada.)

A,CAUTION

3 - The gas piping must not run in or through air ducts,

clothes chutes, gas vents or chimneys, dumb waiters,

or elevator shafts.

4 - The piping should be sloped 1/4 inch (6.4 mm) per 15

feet (4,57 m) upward toward the meter from the fur-

nace. The piping must be supported at proper intervals

[every 8 to 10 feet (2.44 to 3.01 m)] with suitable hang-

ers or straps, Install a drip leg inside vertical pipe runs

to the unit,

5- In some localities, codes may require the installation of

a manual main shut-off valve and union (furnished by

the installer) external to the unit, The union must be of

the ground joint type,

A, IMPORTANT

Gas Supply

1 - This unit is shipped standard for left or right side instal-

lation of gas piping (or top entry in horizontal applica-

tions). Connect the gas supply to the piping assembly.

2 - When connecting the gas supply piping, consider fac-

tors such as length of run, number of fittings, and fur-

nace rating to avoid excessive pressure drop. Table 9

lists recommended pipe sizes for typical applications.

NOTE -Install a 1/8 inch NPT plugged tap in the field piping

upstream of the gas supply connection to the unit. The tap

must be accessible for test gauge connection. See figure 19.

NQ TE -If emergency shutoff is necessarj4 shut off the main

manual gas valve and disconnect main power to the fur-

nace. The installer should properly label these devices.

Nominal

IronPipe

Size

inches

(ram)

3/8

(9.53)

1/2

(12.7)

3/4

(19.05)

(25.4)

1-1/4

(31.75)

1-1/2

(38.1)

(50.8)

2 -1/2

(63.5)

(76.2)

TABLE 9

Gas Pipe Capacity -ft3/hr (m3/hr)

Internal Length of Pipe -feet(m)

Diameter

inches 10 20 30 40 50 60 70 80 90 100

(mm) (3.048) (6.096) (9.144) (12.192) (15.240) (18.288) (21.336) (24.384) (27.432) (30.480)

.493 95 65

(12.522) (2.69) (1.84)

.622 175 120

(17.799) (4.96) (3.40)

.824 360 250

(20.930) (10.19) (7.08)

1.049 680 465

(26.645) (919.25) (13.17)

1.380 1400 950

(35.052) (39.64) (26.90)

1.610 2100 460

(40.894) (59.46) (41.34)

2.067 3950 2750

(52.502) (111.85) (77.87)

2.469 6300 4350

(67.713) (178.39) (123.17)

3.068 11000 7700

(77.927) (311.48) (218.03)

(1.47)

(2.75)

2OO

(5.66)

375

(10.62)

77O

(21.80)

1180

(33.41)

2200

(62.30)

3520

(99.67)

6250

(176.98)

(1.27)

(2.32)

170

(4.81)

32O

(9.06)

66O

(18.69)

990

(28.03)

1900

(53.80)

3000

(84.95

5300

(150.07)

NOTE -Capacity given in cubic feet (In 3) of gas per hour and based

(1.13)

(2.07)

151

(4.28)

285

(8.07)

580

(16.42)

9OO

(25.48)

1680

(47.57)

2650

(75.04)

4750

(134.50)

(1.02)

(1.87)

138

(3.91)

26O

(7.36)

53O

(15.Ol)

81o

(22.94)

1520

(43.04)

2400

(67.96)

4300

(121.76)

(.73)

(1.73)

125

(3.54)

24O

(6.80)

490

(13.87)

75O

(21.24)

1400

(39.64)

2250

(63.71)

3900

(110.43)

(.88)

(1.61)

118

(3.34)

22O

(6.23)

46O

(13.03)

690

(19.54)

1300

(36.81)

2050

(58.05)

3700

(104.77)

(.82)

(1.50)

11o

(3.11)

2O5

(5.80)

430

(12.18)

65O

(18.41)

1220

(34.55)

1950

(55.22)

3450

(97.69)

on O.60 specific gravity gas.

(.76)

(1.42)

103

(2.92)

195

(5.52)

400

(11.33)

62O

(17.56)

1150

(32.56)

1850

(52.38)

3250

(92.03)

Page 20

MANUAL

MAIN SHUT-OFF

VALVE

(With 1/8 in. NPT

Plugged Tap Shown)

GROUND

JOINT

UNION

Left Side Piping

(Standard)

AUTOMATIC

GAS VALVE

(with manual

shut-off valve /

AUTOMATIC MANUAL

GAS VALVE

(with manual VALVE

shut-off valve) (With 1/8 in. NPT

Shown)

JOINT

UNION

DRIP LEG

FIELD

PROVIDED

AND INSTALLED

FIGURE 19

Leak Check

After gas piping is completed, carefully check all piping

connections (factory- and field-installed) for gas leaks, Use

a leak detecting solution or other preferred means.

NOTE -If emergency shutoff is necessa04 shut off the main

manual gas valve and disconnect the main power to the

furnace. The installer should properly label these devices.

Right Side Piping

(Alternate)

ELECTROSTATIC DISCHARGE (ESD)

Precautions and Procedures

&CAUTION

The furnace must be isolated from the gas supply system

by closing its individual manual shut-off valve during any

pressure testing of the gas supply system at pressures less

than or equal to 1/2 psig (3.48 kPa, 14 inches w.c.).

&IMPORTANT

MANUAL MAIN

SHUT-OFF VALVE

WILLNOTHOLD ._.

NORMALTEST _i _

PRESSURE _1]!

CAP /

ISOLATE

GAS VALVE

FIGURE 20

\FURNACE

The unit is equipped with a field make-up box, The make-

up box may be moved to the right side of the furnace to fa-

cilitate installation, If the make-up box is moved to the right

side, the excess wire must be pulled into the blower

compartment. Secure the excess wire to the existing harn-

ess to protect it from damage.

INTERIOR MAKE-UP BOX INSTALLATION

MAKE-UP

BOX

Right Side

FIGURE 21

Page 21

INTERIORMAKE-UP BOX INSTALLATION

MAKE-UP

Left side /BOX

_ °

FIGURE 22

Refer to figure 24 for field wiring and figure 26 for schematic

wiring diagram and troubleshooting.

1 - Select circuit protection and wire size according to the

unit nameplate. The power supply wiring must meet

Class I restrictions,

2 - Holes are on both sides of the furnace cabinet to facili-

tate wiring,

3 - Install a separate disconnect switch (protected by ei-

ther fuse or circuit breaker) near the furnace so that

power can be turned off for servicing,

4 - Before connecting the thermostat or the power wiring,

check to make sure the wires will be long enough for

servicing at a later date, Remove the blower access

panel to check the length of the wire,

5- Complete the wiring connections to the equipment.

Use the provided unit wiring diagram and the field wir-

ing diagram shown in figure 24, Use 18-gauge wire or

larger that is suitable for Class II rating for thermostat

connections,

6 - Electrically ground the unit according to local codes or,

in the absence of local codes, according to the current

National Electric Code (ANSI/NFPA No, 70) for the

USA and current Canadian Electric Code part 1 (CSA

standard C22.1) for Canada. A green ground wire is

provided in the field make-up box,

NOTE -The G5OUH(X) furnace contains electronic

components that are polarity sensitive. Make sure

that the furnace is wired correctly and is properly

grounded.

7 - One line voltage "EAC" terminal is provided on the fur-

nace control board. Any electronic air cleaner rated up

to one amp can be connected to this terminal with the

neutral leg of the circuit being connected to any of the

"NEUTRAL" terminals. See figure 25 for control board

configuration. This terminal is energized when the

blower is operating,

8 - One line voltage "HUM" terminal is provided on the fur-

nace control board, A humidifier rated up to one amp

can be connected to this terminal with the neutral leg

of the circuit being connected to any of the "NEUTRAL"

terminals. See figure 25 for control board configura-

tion. This terminal is energized in the heating mode

whenever the combustion air inducer is operating.

9 - One 24 volt terminal "24V HUM" is provided on the fur-

nace control board. A humidifier rated up to 0.5 amp

can be connected to this terminal with the common leg

of the circuit being connected to the "C" terminal dthe

thermostat terminal block located on the control board.

10-Install the room thermostat according to the instruc-

tions provided with the thermostat. See figure 23 for

thermostat designations. If the furnace is being

matched with a heat pump, refer to the FM21 installa-

tion instruction.

G50UH(X) and CONDENSING UNIT

THERMOSTAT DESIGNATIONS

(Refer to specific thermostat and outdoor unit.)

Thermostat G50UH(X) Condensing

Furnace Unit

PowER

@1 HsuN,T

FIGURE 23

Indoor Blower Speeds

1 - When the thermostat is set to "FAN ON," the indoor

blower will run continuously on the low speed when

there is no cooling or heating demand,

2 - When the G50UH(X)is running in the heating mode,

the indoor blower will run on the heating speed.

3 - When there is a cooling demand, the indoor blower will

run on the cooling speed,

Page 22

TYPICAL G50UH(X) FIELD WIRING DIAGRAM

WARNING-

ELECTRIC SHOCK HAZARD,CAN CAUSE INJURY

OR DEATH.UNIT MUST BE GROUNDED IN ACCORDANCE

WITH NATIONAL AND LOCAL CODES,

IF ANY WIRE IN THIS APPLIANCE IS REPLACED, IT

MUST BE REPLACED WITH WIRE OF LIKE SIZE,

RATING,INSULATION THICKNESS AND TERMINATION.

_ IMPORTANT-

TO PREVENT MOTOR BURNOUT,NEVER CONNECT MORE

THAN ONE MOTOR LEAD TO ANY ONE CONNECTION.

PARK TERMINALS ARE UNPOWERED TERMINALS. ALL

UNUSED MOTOR LEADS MUST BE WIRED TO A

PARK TERMINAL.

/:Zk FOR CORRECT NUMBER OF SECONDARY

LIMITS USED,SEE SECONDARY LIMIT

SECTION OF BLOWER SPEED CHART.

FOR 650UH-56B-90 AND

G5OUH-4BC-135 ONLY.DO NOT USE

RED (LOW SPEED) MOTOR LEAD

FOR HEATING SPEED. LEAVE ON

PARK OR USE FOR CONTINUOUS AIR

CIRCULATION(FAN).

FIELD SUPPLIED ACC.IIRE.

./6'kUSE COPPER CONDUCTORS ONLY.

/Z_X 24V HUM IS A I/4" FEMALE OUICK

CONNECT TERMINAL

---- FIELD INSTALLED CLASS II24V

-- FIELD INSTALLED LINE VOLTAGE

{_V ACC

K43 EC(_

(IF USEO)

L I-_=======_

GS{g

S{O COIlBIJ_ITION AIR

_IIIARYGAS PROVIi_ SWITCH

LIMIT C(_WBIJSTI(_NAIR

(_) INN.ICERI_T_

{ALEImNATE}

-'e

-- V_lTE-R(X)GERS HONEYWELL

6A5 VALVE 6AS VALVE

,, orlo 000

FLAMEROLLOUT _ FLAI_ I_NITERIR3$1 S47

SWITCH SENS_ J,_ _A_ _LLOm

m_=l _r_

TRANSFORMER

A_ _

I_ITI(_W _ CB8_ _ S2I

:O_TROL _, CIRCUIT SECONE)ARY

PIS_ _" BREAKER 6AS LIIIIT

(_4: P135

J,3_F::F::I

ROOM THIZRMOSTAT [E{) _)@_)

I I I I I _SECONDARY

6AS LIMIT

'1 _1,._.... .,1'Ill, _

I I i'---- "-------la J III INOOOe

C4 BLOWERMOTO_

_' _ _ JICAPACITOR

OUTB:_ al l(9

U.,T r--- ....

FIGURE 24

INTEGRATED CONTROL BOARD

COOL

HEAT

PARK

FAN

EAC

XFMR

LINE

HUM

5 Terminals

24V HUM

TEll\ IINAL DESIGNATIONS

Blower- Cooling Speed (120MAC)

Blower - Heating Speed (120VAC)

Unused Blower (Not energized)

Continuous Low Blower Speed

Accessory Terminal (120VAC)

Transformer (120VAC)

Input (120VAC)

Heat Only Accessory (120VAC)

120 Volt Neutral

Flame Sensor

Heat Only Accessory (24VAC)

1/4" FEMALE

QUICK

CONNECT

SI DIP SWITCHES

HEAT OFF DELAY

l 2 SEC

OFF OFF 60

OFF ON 90 *

ON OFF 120

ON ON 180

COOL OFF DELAY

3 _ SEC

OFF _ 2 *

ON _ 45

*Factory setting

FIGURE 25

Page 23

G5OUH(X) Schematic Wiring Diagram

120V ADO /_ SIS BLOWER SPEED CHART L_

OR SlO COMBUSTION AIR FACTORY CONNECTED SPEED TAPS MOTOR SECONDARY

PROVING SWITCH SREE_

K43 ECON PRIMARY GAS UNIT COOL HEAT FAN PARK PARK AVAIL, L_DTS

(IF USED) LIMIT COMBUSTION AIR _24A-045 fELLOW RED ........ 3 N/A

INDUCER MOTOR 2¢A-070 fELLOW RED 32

"-L£P./ 36A-070 fELLOW RED .... BROWN 4 2

36B-090 _ BROWN RED .... YELLOt 4{(RIGHT)

(ALTERNATE) _<BROWN RED .... YELLO_ €I(RISHT)

o o° o....,ELLo,,

GVf6V I4BC- 135 BROWN RED .... t'ELLO£t 4- _

60C-t JO fELLOW RED .... BROWN 4I(R=eHT}

60D- 135 fELLOW RED .... BROWN 4- 2

WHITE-RODGER9 HONEYWELL 6DO° 155 fELLOW RED .... BROWN 42

/_ GAS VALVE GAS VALVE HX BLOWER_ - SPEED SELECTION LO

0 _ SPEED BLACK Y_LI.QW RED 3

BURNERS TAPS BLACK BROWN YELLOW RED 4-

0[] 0 0 0 T.ERMOOTAT.EATANTICIPATIONSETTINES

PLANENOLLDUT\FLAMEI_NITER"_L_SAT

SWITCH SENSOR JI59 FLAME ROLLOU'[

JACKPLU6 CHART

P159 E_ SWITCH IJ.P5B IJACK/PLUG-GURNER CONTROL

DOOR TRANSFORMER IJ.PIB9 IJACK/PLUD-IONITION

INTERLOCI WARN INO-

OR DEATH.UNIT MUST BE GROUNDED IN ACCORDANCE

A92 _ ELECTRIC SHOCK HAZARD,CAN CAUSE INJURY

BLO_R

IGNITION COB c $21 WITH NATIONAL AND LOCAL CODES.

CONTROLpIs6 CIROOI SECONDARY IF ANY WIRE IN THIS APPLIANCE IS RSPLACED,IT

6REANEf GAS LIMIT MUST 6E REPLACED WITH WIRE OF LIKE SIZE,

(EA-) RATING,INSULATION THICKNESS AND TERMINATION,

PIJS

JI35_ _ IMPORTANT-

TO PREVENT MOTOR DURMDUT,REVER CONNECT MORE

SI P50 THAN ONE MOTOR LEAD TO ANY ONE CONNECTION.

ROOM THERMOSTAT (El) Z_ PARK TERMINALS ARE UNPOWEREDTERMINALS. ALL

i®®.o®ol UNOREDMOTORLEAOOMUST6EWIREDTOA

"" " 9ZI PARK TERMINAL.

IIIIIl_(_I SECONDARY i:& FOR CORRECT NUM6ER OF SECONDARY

I•--If-" " • "'_k GAS LIMIT _LIMITS USED,SEE SECONDARY LIMIT SI

IIiIL .... j I II I II A SECTION OF BLOWER SPEED CHART. ROOM THERMOSTAT

li ,- .-, ,,I , "= .. /Ax FOR G5DUH-3OO-90 AND ._ _ _ _..

=I. ..... "1 .I I I iDo OODUH-4-BC-135 ONLY,DO NOT USE LJ'-c>P_R \

l IL ...... i= = ,,I IINDOOR RED (LOW SPEED) MOTOR LEAD -T- I Iv.L _nN.-L,I

[........ II I J I C4- 6LO_R MOTOR FOR HEATING SPEED. LEAVE ON ,_ I I _') N _ ,_-"%'tI

........... = .... ' CAPACITOR _PARK OR USE FOR OONTINOOUS AIR _o'l I I /"_-_]C ..I.I'-_FANI

OUTDO(._ I IF-------I /\CIRCULATION(FAN), T_'II _0 C) r(3 I )-,'"1

UNI<"r...... "'I I (;_FIELOSH_LIEOAOO.WIRE._?_&ll..do-t_E___.YI

F-T-l, r........... " _ _ ,_ USECOPPERCONDUCTORSONLY. Y '1I"°_L_ _oo%L /

....... A zAv,uMISA,,4-"FEMALEOOICKL I\ _ Lp L_ J

JCONNECT TERMINAL

$51 _LINE VOLTAGE FIELD INSTALLED

- 0O0R,NTERL K_---CLASSiiVOLTAREFIELD,IRINO....

L, _-0_ _ DENOTES OPTIONAL COMPONENTS .u. _ _._ _ _

I-@ .... -_CK I,Z_ II ,KS II

x_ . 24-_T I 1 Ilk- = I

IZOVAC ' VAC o-- N -- _ I

K,€ -_K; I ._I/---_V P98 "-./ "4/ "-./_ _ "_L...--",P96 S_. _I/

_L I /'z, 9 _ ,_" J962 _ 4- "y" _ _'JSD '_"'_" '_-

._-JISS r- r- r_

I"''T II ,o;,. 0v,

PI59_/ I I I / _,_ O=_

R35 _SPE_FEDCHART YELLOW

JI59, sot

PI59_

A9Z J I

EQUIPMENT

WHITE

FIGURE 26

Page 24

FOR YOUR SAFETY READ BEFORE LIGHTING

AWARNING

ACAUTION

BEFORE LIGHTING smell all around the appliance area for

gas, Be sure to smell next to the floor because some gas is

heavier than air and will settle on the floor.

The gas valve on the G50UH(X) unit may be equipped with

either a gas control knob or gas control lever. Use only your

hand to push the lever or to tum the gas control knob. Never

use tools, If the knob will not turn or if the lever will not move

by hand, do not try to repair it. Call a qualified service tech-

nician, Force or attempted repair may result in a fire or ex-

plosion,

Placing the furnace into operation:

G50UH(X) units are equipped with a SureLight ® ignition

system. Do not attempt to manually light burners on these

furnaces, Each time the thermostat calls for heat, the

burners will automatically light. The ignitor does not get

hot when there is no call for heat on units with SureLight ®

ignition system,

AWARNING

Gas Valve Operation (Figures 27, 28 and 29)

1 - STOP! Read the safety information at the beginning of

this section,

2 - Set the thermostat to the lowest setting,

3 - Turn off all electrical power to the unit,

4-This furnace is equipped with an ignition device which

automatically lights the burners, Do not try to light the

burners by hand,

5- Remove the upper access panel,

6 - Honeywell VR8205 Gas Valve with ON/OFF Switch

- Move gas valve switch to OFF, See figure 27.

Honeywell VR8205 Gas Valve with Control Knob -

Turn knob on gas valve clockwise 41_ to OFF. Do not

force, See figure 28,

White Rodgers 36G Gas Valve - Move gas valve

switch to OFF. See figure 29,

7 - Wait five minutes to clear out any gas. If you then smell

gas, STOP! Immediately call your gas supplier from a

neighbor's phone. Follow the gas supplier's instruc-

tions. If you do not smell gas go to next step.

Honeywell VR8205 Series Gas Valve

MANIFOLD (With On/Off Switch)

PRESSURE MANIFOLD

SCREW PRESSURE

(under cap) OUTLET

GAS VALVE ON/OFF SWITCH SHOWN IN OFF POSITION

FIGURE 27

Honeywell VR8205 Series Gas Valve

with Gas Control Knob

MANIFOLD MANIFOLD

PRESSURE ._ _ PRESSURE

ADJUSTMENT"'_'___,_, r I h _'_'l_, OUTLET

SCREW _

GAS VALVE SHOWN IN OFF POSITION

FIGURE 28

White Rodgers 36G Series Gas Valve

PRESSURE

POST

MANIFOLD

PRESSURE

ADJUSTMENT

SCREW

(Undercover

SCOW)

GAS VALVE SHOWN IN OFF POSITION

FIGURE 29

Page 25

8- Honeywell VR8205 Gas Valve with ON/OFF Switch

- Move gas valve switch to ON. See figure 27.

Honeywell VR8205 Gas Valve with Control Knob -

Turn knob on gas valve counterclockwise _ to ON,

Do not force. See figure 28,

White Rodgers 36G Gas Valve - Move gas valve

switch to ON, See figure 29,

9 - Replace the upper access panel,

10- Turn on all electrical power to to the unit,

11- Set the thermostat to desired setting,

NOTE -When unit is initially started, steps 1 through 11

may need to be repeated to purge air from gas line,

12- If the appliance will not operate, follow the instructions

"Turning Off Gas to Unit" and call your service techni-

cian or gas supplier,

Turning Off Gas to Unit

1 - Set the thermostat to the lowest setting,

2 - Turn off all electrical power to the unit if service is to be

performed,

3 - Remove the upper access panel,

4 - Honeywell VR8205 Gas Valve with ON/OFF Switch

- Move gas valve switch to OFF, See figure 27.

Honeywell VR8205 Gas Valve with Control Knob -

Turn knob on gas valve clockwise clio to OFF, Do not

force, See figure 28,

White Rodgers 36G Gas Valve - Move gas valve

switch to OFF, See figure 29,

5 - Replace the upper access panel.

Heating Sequence Of Operation

1-When thermostat calls for heat, combustion air inducer

starts,

2 - Combustion air pressure switch proves combustion air

inducer operation. Switch is factory set and requires no

adjustment,

3 - After a 15 second prepurge, the hot surface ignitor en-

ergizes,

4- After a 20 second ignitor warm-up period, the gas

valve solenoid opens,

5 - Gas is ignited, flame sensor proves the flame, and the

combustion process continues,

6 - If flame is not detected after first ignition trial, the igni-

tion control will repeat steps 3 and 4 four more times

before locking out the gas valve ("WATCHGUARD"

flame failure mode), The ignition control will then auto-

matically repeat steps 3, 4, 5, and 6 after 60 minutes,

7- To interrupt the 60-minute "WATCHGUARD" period,

move thermostat from "Heat" to "OFF" then back to

"Heat", Heating sequence then restarts at step 1.

Gas Flow (Approximate)

1 - Operate unit at least 15 minutes before checking gas

flow. Determine the time in seconds for one revolu-

tions of gas through the meter, A portable LP gas me-

ter (17Y44) is available for LP applications,

2 - Compare the number of seconds and the gas meter

size in table 10 to determine the gas flow rate. Multiply

the gas flow rate by the heating value to determine the

unit input rate, If manifold pressure is correct and the

unit input rate is incorrect, check gas orifices for proper

size and restriction,

3 - Remove temporary gas meter if installed,

NOTE -To obtain accurate reading, shut off all other gas

appliances connected to meter,

TABLE 10

Gas Flow Rate (Ft.'_/Hr.)

Seconds for 1

Revolution

Gas Pressure

Gas Meter Size

1/2 cu ft Dial 1 cu ft Dial

180 360

150 300

129 257

113 225

100 200

90 180

82 164

75 150

69 138

64 129

60 120

56 113

53 106

50 100

47 95

45 90

43 86

41 82

39 78

38 75

36 72

35 69

33 67

32 64

31 62

30 60

1 - Check the gas line pressure with the unit firing at maxi-

mum rate. A minimum of 4.5 in, w.c. for natural gas or

11,0 in, w,c, for LP/propane gas should be maintained,

2- After the line pressure has been checked and ad-

justed, check the manifold pressure. A natural gas to

LP/propane gas changeover kit is required to convert

the unit, Manifold pressure for all units fueled by natu-

Page 26

ralgasatallaltitudesis3.5"w.c.Manifoldpressurefor

allunitsfueledbyL.R/propanegasat allaltitudesis

10.0"w,c.Seefigures27,28and29forthelocationof

themanifoldpressureadjustmentscrews,

NOTE -In Canada, certification for installations at eleva-

tions over 4500 feet (1372 m) is the jurisdiction of local au-

thorities.

Manifold pressure for all units fueled by natural gas at all

altitudes is 3.5" w,c, Manifold pressure for all units fueled

by L,R/propane gas at all altitudes is 10,0" w,c,

NOTE -A natural to L.R propane gas changeover kit is nec-

essary to convert this un#. L.R conversion kit 25W20 is

used with all units installed at altitudes up to 7,500 feet. L.P.

conversion kit 25W21 is used with all units installed at alti-

tudes from 7,501 to 10,000 feet above sea level. Refer to

the changeover kit installation instruction for the conver-

sion procedure.

NOTE -Units fueled by natural gas and installed at alti-

tudes of 7501-10,000 feet above sea level require instal-

lation of a high altitude orifice kit (59M17).

The combustion air pressure switches are factory-set and

require no adjustment, The existing unit pressure switch

must be replaced by pressure switch 56L32 for G50UH(X)

units installed at altitudes from 7,501 to 10,000 feet above

sea level,

Primary and Secondary Limits

The primary limit is located on the heating compartment

vestibule panel. The secondary limits (if equipped) are lo-

cated in the blower compartment, attached to the back side

of the blower. These limits are factory set and require no

adjustment.

Flame Rollout Switches (Two)

These manually reset switches are located on (or inside of)

the burner box, If tripped, check for adequate combustion

air before resetting,

Pressure Switch

The pressure switch is located in the heating compartment

adjacent to the combustion air inducer. This switch checks

for proper combustion air inducer operation before allow-

ing ignition trial, The switch is factory-set and requires no

adjustment.

Temperature Rise

Place the unit into operation with a heating demand, After

supply and return air temperatures have stabilized, check

the temperature rise, If necessary, adjust the blower speed

to maintain the temperature rise within the range shown on

the unit nameplate, Increase the blower speed to decrease

the temperature, Decrease the blower speed to increase

the temperature rise, Failure to do adjust the temperature

rise may cause erratic limit operation,

Fan Control

Heating Mode -- The fan on delay of 45 seconds is not ad-

justable. The fan offdelay (amount of time that the blower

operates after the heat demand has been satisfied) may

be adjusted by setting $1 switches 1and 2 located on the

SureLight ® control. The unit is shipped with a factory fan

off setting of 90 seconds, The fan off delay affects com-

fort and is adjustable to satisfy individual applications.

Adjust the fan off delay to achieve a supply air tempera-

ture between 90 ° and 110° F at the exact moment that the

blower is de-energized. Longer offdelay settings provide

lower return air temperatures; shorter settings provide

higher return air temperatures. See figure 25.

Cooling Mode --The cooling mode fan off delay (amount

of time that the blower operates after the cooling demand

has been satisfied) may be adjusted by setting $1 switch

3 located on the SureLight ® control, In the off position,

the cooling fan off delay is 2 seconds. In the on position,

the cooling fan off delay is 45 seconds, See figure 25,

Thermostat Heat Anticipation

Set the heat anticipator setting (if adjustable) according to

the amp draw listed on the wiring diagram that is attached

to the unit.

Electrical

1 - Check all wiring for loose connections,

2 - Check for the correct voltage at the furnace (furnace

operating).

3 - Check amp-draw on the blower motor.

Motor Nameplate Actual

NOTE -Do not secure the electrical conduit directly to the

air ducts or structure.

Blower Speeds

NOTE - CFM readings are taken external to unit with a dry

evaporator coil and without accessories.

1 - Turn off electrical power to furnace,

2 - Remove blower access panel.

3 - Disconnect existing speed tap at control board speed

terminal.

NOTE -Termination of any unused motor leads must be

insulated.

4 - Refer to blower speed selection chart on unit wiring dia-

gram for desired heating or cooling speed.

5- Connect selected speed tap at control board speed

terminal.

6 - Resecure blower access panel.

7 - Turn on electrical power to furnace,

Electronic Ignition

The SureLight @integrated control has an added feature of

an internal Watchguard control, The feature serves as an

automatic reset device for ignition control lockout caused

by ignition failure, After one hour of continuous thermostat

demand for heat, the Watchguard will break and remake

thermostat demand to the furnace and automatically reset

the control to begin the ignition sequence,

Page 27

FlueAndChimney

1- Checkfluepipe,chimneyandallconnectionsfortight-

nessandtomakesurethereisnoblockage,

2 - Checkunitforproperdraft,

3- Ispressureswitchclosed?Obstructedfluewillcause

unittoshutoffatpressureswitch,Checkflueandoutlet

forblockages.

4- Resetmanualflamerolloutswitcheson burnerbox

cover.

FailureToOperate

Iftheunitfailstooperate,checkthefollowing:

1- Isthethermostatcallingforheat?

2 - Areaccesspanelssecurelyinplace?

3- Isthemaindisconnectswitchclosed?

4 - Istherea blownfuse?

5- Isthefilterdirtyorplugged?Dirtyorpluggedfilterswill

causethelimitcontroltoshuttheunitoff.

6 - Isgasturnedonatthemeter?

7- Isthemanualmainshut-offvalveopen?

8- Istheinternalmanualshut-offvalveopen?

9- Istheunitignitionsysteminlockout?Iftheunitlocksout

again,calltheservicetechniciantoinspecttheunitfor

blockages.

,AWARNING

A,CAUTION

At the beginning of each heating season, a qualified techni-

cian should check the system as follows:

Blower

Check the blower wheel for debris and clean if necessary.

The blower motors are prelubricated for extended bearing

life. No further lubrication is needed.

,&WARNING

Filters

All G50UH(X) filters are installed external to the unit. Filters

should be inspected monthly. Clean or replace the filters

when necessary to ensure that the furnace operates prop-

erly. Replacement filters must be rated for high velocity air-

flow. Table 1 lists recommended filter sizes.

Flue And Chimney

Check the flue pipe, chimney and all connections for tight-

ness and to make sure there is no blockage,

Electrical

1 - Check all wiring for loose connections.

2 - Check for the correct voltage at the furnace (furnace

operating),

3 - Check amp-draw on the blower motor.

Motor Nameplate Actual

Cleaning the Heat Exchanger and Burners

NOTE -Use papers or protective covering in front of the fur-

nace during cleaning.

Cleaning the heat exchanger requires a steel spring

"snake," a reversible drill and a vacuum cleaner, The steel

spring snake may be constructed by purchasing a 4 ft. long

by 1/4 inch diameter steel wire cable and a 1/4 inch diame-

ter wire brush, These items are available at a hardware

store. Insert wire end of brush into the open end of the

spring cable. Crimp the cable around the brush so that the

brush is secured and will not come off during cleaning, At-

tach the other end of the cable to the reversible drill to com-

plete the tool for cleaning the heat exchanger.

1 - Turn off both electrical and gas power supplies to fur-

nace.

2 - Remove flue pipe and top cap from the unit. Label the

pressure switch wires, then disconnect them.

3 - Remove the four screws that secure the combustion air

inducer. Carefully remove the combustion air inducer to

avoid damaging blower gasket. If gasket is damaged, it

must be replaced to prevent leakage. See figure 30.

G50UH(X) BURNER & HEAT

EXCHANGER REMOVAL

HEAT

BURNER BOX ASSEMBLY

FIGURE 30

Page 28

4- Removethecollectorboxlocatedbehindthecombus-

tionairinducer.Becarefulwiththecollectorboxgas-

ket.Ifthegasketisdamaged,it mustbereplacedto

preventleakage,

5- Labelthewiresfromgasvalveandrolloutswitches,

thendisconnectthem.

6- Disconnectgassupplypiping.Removefourscrewsse-

curingtheburnermanifoldassemblytothevestibule

panelandremovetheassemblyfromtheunit,

NOx INSERTS

(X models only)

FIGURE 31

7 - NOx units only- Remove the three screws that attach

the NOx insert to the corbel at the entrance to each

heat exchanger section, Carefully remove the NOx in-

sert from each section, See figure 31.

8 - Insert the brush end of cable snake into the top of one

of the heat exchanger openings, Do not force the

cable into the heat exchanger. Insert the cable and

operate the drill on slow speed. Move the cable in and

out of the heat exchanger section three or four times or

until sufficient cleaning is accomplished. Reverse drill

and slowly work the cable out of opening,

9- Repeat procedure for each heat exchanger section.

10- After each of the top heat exchanger sections has been

cleaned, insert the brush end of the cable snake into

the bottom openings of each of the heat exchanger

sections and clean as described in step 8,

11- Remove the cable from the heat exchanger. Use a vac-

uum cleaner to remove debris knocked loose during

cleaning.

12- Attach the exhaust end (positive pressure) of the vacu-

um cleaner to the top of the heat exchanger section,

Any loose debris will be forced to the bottom of the heat

exchanger section, Vacuum debris from bottom open-

ings.

13- Replace collector box and combustion air inducer.

Check gaskets for damage. Damaged gaskets must be

replaced to avoid heat exchanger leaks. Replace all

screws to the collector box and combustion air inducer.

Failure to replace all screws may cause leaks,

14- To clean the burner, run a vacuum cleaner with a soft

brush attachment over the face of burners. Visually in-

spect inside the burners and crossovers for any blockage

caused by foreign matter. Remove any blockage,

15- NOx Units -Reattach the NOx inserts to the corbels at

the entrance to each heat exchanger opening, See fig-

ure 31,

16- Replace burner/manifold assembly onto the vestibule

panel,

17- Reconnect wires to pressure switch, roll-out switches,

gas valve and combustion air inducer. Refer to unit wir-

ing diagram,

18- Reconnect vent pipe to combustion air inducer outlet,

19- Reconnect gas supply piping,

20- Turn on power and gas supply to unit,

21- Set thermostat and check for proper operation,

22- Check all piping connections, factory and field, for gas

leaks. Use a leak detecting solution or other preferred

means,

AkCAUTION

23- Ira leak is detected, shut gas and electricity offand

repair leak,

24- Repeat steps 23 and 24 until no leaks are detected.

25- Replace front access panel.

Page 29

ThefollowingrepairpartsareavailablethroughLennoxdealers.Whenorderingparts,includethecompletefurnacemodel

numberlistedontheCSAInternationalnameplate--Example:G50UH(X)-24A-045-8,

CabinetParts

Upperaccesspanel

Blowerpanel

Topcap

ControlPanelParts

Transformer

SureLight®ignitionboard

Doorinterlockswitch

Circuitbreaker

BlowerParts

Blowerwheel

Motor

Motormountingframe

Motorcapacitor

Blowerhousingcutoffplate

HeatingParts

FlameSensor

Heatexchangerassembly

Gasmanifold

Combustionairinducer

Gasvalve

Mainburnercluster

Mainburnerorifices

Pressureswitch

Ignitor

Primarylimitcontrol

Flamerolloutswitch

Secondarylimit(notusedon24A-45-1)

DIAGNOSTIC CODES

Make sure to Identify LED'S Correctly.

Refer to Installation Instructions for control board layout,

DSl DS2 DESCRIPTION

(Red or Green) (Green)

SIMULTANEOUS SIMULTANEOUS Power on -- Normal operation.

SLOW FLASH SLOW FLASH Also signaled during cooling and continuous fan.

SIMULTANEOUS SIMULTANEOUS Normal operation -- Signaled when heating demand initiated at thermostat.

FAST FLASH FAST FLASH

SLOW FLASH ON Primary or secondary limit switch open. Limit must close within 3 minutes or unit

goes into 1-hour Watchguard.

Pressure switch open;

OR: Blocked inlet/exhaust vent;

OFF SLOW FLASH OR: Condensate line blocked;

OR: Pressure switch closed prior to activation of combustion air inducer.

ALTERNATING ALTERNATING Watchguard -- Burners failed to ignite, limit open longer than 3 minutes, or flame

SLOW FLASH SLOW FLASH sense lost 5 times in one heating cycle.

SLOW FLASH OFF Flame sensed without gas valve energized.

ON SLOW FLASH Rollout switch open.

ON ON

Circuit board failure or control wired incorrectly. Check 24-volt and 115-volt

ON OFF connections to board.

OFF ON

FAST FLASH SLOW FLASH Main power polarity reversed. Switch line and neutral. Improper main ground.

SLOW FLASH FAST FLASH Low flame signal. Check flame sensor.

The following conditions are sensed during the ignitor warm-up period only:

ALTERNATING ALTERNATING 1) Improper main ground;

FAST FLASH FAST FLASH 2) Broken ignitor; OR: Open ignitor circuit;

3) Line voltage below 75 volts.

NOTE -Slow flash rate equals 1 Hz (one flash per second). Fast flash rate equals 3 Hz (three flashes per second).

Drop out flame sense current =0.15 -0.24 microAmps.

Page 30

SURELIGHT®CONTROL

HEATING SEQUENCE OF OPERATION

NORMAL HEATING MODE ABNORMAL HEATING MODE

IPOWER ON ]I GAS VALVE OFF. COMBUSTION AIR INDUCER ON.

_' I INDOOR BLOWER ON.

CONTROL SELF-CHECK OKAY'_ I,_ _ LED #1 ALTERNATING FAST FLASH

I";NO | LED#2 ALTERNATING FAST FLASH

I | CHECK FOR BROKEN IGNITOR OR

-I GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.

vaYES _ INDOOR BLOWER DELAY OFF.

,sPOLARITYREVERSED? _1 I LED#1ON

I i- I I I LED #2 ON

IINO /I I (R__ TURNING MAIN POWER OFF)

LED#1 AND LED#2 /

ALTERNATING FAST J_ 1' _ POLARITY REVERSED.

FLASH, SIGNAL NO • I LED #1 -- FAST FLASH

HOLDS UNTIL UNIT IS| ._--I ISTHERE IYESI ISVOLTAGE INO ILED #2 -- SLOW FLASH

PROPERLY GROUNDi_I PROPER GROUND? _ ABOVE 75 VOLTS? I_-----I'

-- ' YES/ II _I LED#1ANDLED#2ALTERNATINGFASTI

•NO I'--ml FLASH. SIGNAL HOLDS UNTIL VOLTAGE I

_I ROLLOUT SWITCH CLOSED? _ I_ I RISES ABOVE 75 VOLTS. I

YESi in,--

| I1"I"1 GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.

'_ _1 INDOOR BLOWER OFF WITH DELAY.

GAS VALVE I I LED #1 -- ON. LED #2 -- SLOW FLASH,

I DE-ENERGIZED? I ISEQUENCE HOLDS UNTIL ROLLOUT SWITCH CLOSES.

YEs_

NORMAL OPERATION: I

LED #1 -- SLOW FLASH

LED #2 -- SLOW FLASH

THERMOSTAT CALLS FOR HEAT: I

LED #1 -- FAST FLASH ILED #2 -- FAST FLASH

YES NO

IS COMBUSTION AIR I

PRESSURE SWITCH OPEN? 14

YES _1

I IS COMBUSTION AIR INDUCER ENERGIZED?

(HUM TERMINAL IS ENERGIZED WITH C.A.I.) 4

HAS COMBUSTION AIR PRESSURESWITCH CLOSED IN 2.5 MINUTES?

YES

15-SECOND COMBUSTION AIR INDUCER PREPURGE I

| N T ATED BY CLOSED PRESSURE SW TCH. I

YES

CONTINUED NEXT PAGE

GAS VALVE OFF.

COMBUSTION AIR INDUCER OFF.

INDOOR BLOWER OFF WITH DELAY.

LED #1 OFF

LED #2 SLOW FLASH

(Sequence holds until pressure switch

closes or thermostat resets control,)

PRESSURE SWITCH IS IN WATCHGUARD MODE.

GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.

INDOOR BLOWER OFF WITH DELAY,

LED #1 -- OFF. LED #2 -- SLOW FLASH,

IS 5-MINUTE RESET PERIOD COMPLETE?

Page 31

NORMAL HEATING MODE

15-SECOND COMBUSTION AIR INDUCER PREPURGE 9

N T ATED BY CLOSED PRESSURE SW TCH.

YES _

I IGNITOR WARM-UP -- 20 SECONDS.

YES

I 4-SECOND TRIAL FOR IGNITION.

GAS VALVE OPENS, IGNITOR ENERGIZED FOR

UP TO 4 SECONDS,

YES

I FLAME STABILIZATION PERIOD.

4 SECONDS

FLAME RECTIFICATION CURRENT

CHECK. CAN FLAME BE PROVEN WITHIN

4 SECONDS AFTER GAS VALVE OPENS?

( > 0.24 microamps)

YES _

ABNORMAL HEATING MODE

FLAME PRESENT?

YES _

I FLAME SIGNAL ABOVE 0.31 MICROAMPS?

YES _

I INDOOR BLOWER ON DELAY BEGINS

(45 seconds,)

YES _1

PRIMARY AND SECONDARY LIMITSWITCHES CLOSED?

YES

÷1

I ROLLOUT SWITCH CLOSED?

YES _

COMBUSTION AIR PRESSURE

SWITCH CLOSED?

YES _

THERMOSTAT DEMAND SATISFIED.

YES

LED #1 & #2 SIMULTANEOUS SLOW FLASHES.

YES _

COMB. AIR INDUCER CONTINUES 5-SECOND

POST PURGE AFTER T'STAT DEMAND IS SATISFIED,

INDOOR AIR BLOWER COMPLETES SELECTED "OFF"

DELAY BEFORE SHUTTING OFF.

-_O S VOLTAGE ABOVE 75 VOLTS?

YES_ . NO I

_IIW ISTHERE A PROPER GROUND? I--=-_l

YES_t INOI

ISIGNITOR INTACT AND CONNECTED?I_"I

LEDS SIGNAL

ALTERNATING

FAST FLASH

I GAS VALVE OFF. COMBUSTION AIR INDUCER ON.

INDOOR BLOWER OFF. I

HAS CONTROL FA LED TO SENSE FLAME FOR NO

FIVE CONSECUTIVE TRIES DURING A SINGLE

I HEAT DEMAND?

I_ IGNITION WATCHGUARD MODE. GAS VALVE OFF. I YES

COMBUSTION AIR INDUCER OFF. |

INDOOR BLOWER OFF WITH DELAY

LED 1 ALT. SLOW FLASH LED 2 ALT SLOW FLASH I I

IS 60-MINUTE RESET PERIOD COMPLETE? I,.__ I

_,Z_._I

HASCONTROLRESET,GN,T,ON

I I SEQUENCE FOUR TIMES? /

- I

F-

LOW FLAME SIGNAL

(Does not affect operation of control)

LED #1 -- SLOW FLASH

LED #2 -- FAST FLASH

GAS VALVE DE-ENERGIZED

COMBUSTION AIR INDUCER

DE-ENERGIZED.INDOOR BLOWER

ON UNTIL SWITCH CLOSES.LED #1

-- SLOW FLASH, LED #2 -- ON.

IS LIMIT SWITCH CLOSED?

YES

HAS PRIMARY/SECONDARY LIMIT

RESET (CLOSED) WITHIN 3

MINUTES?

YESl

LIMIT SWITCH WATCH-

GUARD MODE. GAS

VALVE OFF. COMB. AIR

INDUCER OFF. INDOOR

BLOWER OFF WITH

DELAY, LED#I-SLOW

FLASH LED#2 - ON. IS

60MINUTE RESET

PERIOD COMPLETE?

YES

GAS VALVE POWER OFR

COMBUSTION AIR INDUCER POWER OFF.

INDOOR BLOWER OFF WITH DELAY

LED #1 -- ON. LED #2 -- SLOW FLASH,

SEQUENCE HOLDS UNTIL ROLLOUT SWITCH IS RESET

I GAS VALVE DE-ENERGIZED

COMBUSTION AIR INDUCER ON.

INDOOR BLOWER OFF WITH DELAY

LED #1 -- OFF. LED #2 -- SLOW FLASH,

HAS CAB SWITCH CLOSED IN 2.5 MINUTES?

NO_

I 5-MINUTE PRESSURE SWITCH

WATCHGUARD MODE,

YES

]

Page 32

SURELIGHT®CONTROL

COOLINGSEQUENCEOF OPERATION

NORMALCOOLING MODE ABNORMALCOOLING MODE

I POWER ON l

I IGNITIONCONTROLMA,NPOWERON I

I CO.T O S O,A .OS ,OO. OKIS CONTROL OPERATING NORMALLY?

GAS VALVE OFF, COMBUSTION AIR INDUCER OFR

INDOOR BLOWER OFF WITH NORMAL DELAY.

SIGNAL CIRCUIT BOARD FAILURE AT LED.

INTERRUPT MAIN POWER TO RESET CONTROL,

Y sJ

I ,sPOLARITYREVERSED?_ LED_IFASTFLASHLED_2SLOWFLASHI

LED#1 AND LED#2 NO |

ALTERNATING FAST I NO _ __ _ LED#1 AND LED#2 ALTERNATING FAST

FLASH. SIGNAL _ IS THERE I YESJ Is VOLTAGE FLASH. SIGNAL HOLDS UNTIL VOLTAGE

I HOLDS UNTIL UNIT IS I_1 PROPER GROUND? I_IABOVE 75 VOLTS? I_' RISES ABOVE 75 VOLTS.

[PROPERLY GROUND. I I

•NO I GAS VALVE OFF COMBUSTION AIR INDUCER OFF

I ROLLOUT SWITCH MONITORED CONTINUOUSLY. _ INDOOR BLOWER OFF WITH NORMAL DELAY.

IS ROLLOUT SWITCH CLOSED? I_--I SIGNAL CIRCUIT BOARD FAILURE AT LED,

YESl - ISEQUENCEHOLDS UNTIL ROLLOUT SWITCH CLOSES.

I CHECK TO ENSURE GAS VALVE IS DE-ENERGIZED.

S GAS VALVE OFF?

I LED:SLOW FLASHRATEREMAINSUNCHANGED ITHROUGHOUT COOLING CYCLE.

ITHERMOSTAT CALLS FOR COOLING. I

COMPRESSOR CONTACTOR IS ENERGIZED,

INDOOR BLOWER ON COOL SPEED AND EAC

TERM NAL S ENERG ZED AFTER 2-SECOND DELAY,

THERMOSTAT OPENS. I

COMPRESSOR OFF. I

SYSTEM FAN AND EAC TERM, OFF I

WITH 2 OR 45-SECOND DELAY, I

Page 33

SURELIGHT ® CONTROL

CONTINUOUS FAN SEQUENCE OF OPERATION

LED: SLOW FLASH RATE REMAINS I

UNCHANGED THROUGHOUT SEQUENCE.

MANUAL FAN SELECTION MADE AT THERMOSTAT.

CONTROL (G) ENERGIZES INDOOR BLOWER AT

FAN SPEED. EAC TERM. IS ENERGIZED.

THERMOSTAT CALLS FOR HEAT (W). I--l't

THERMOSTAT CALLS FOR COOLING.

_YES

INDOOR BLOWER SWITCHES TO COOL SPEED.

THERMOSTAT OPENS.

YEs I

AFTER NORMAL DELAY.

I THERMOSTAT OPENS. COMBUSTION AIR INDUCER I

AND HUM TERMINAL ARE DE-ENERGIZED.

JINDOOR BLOWER SELECTED TIME OFF DELAY BEGINS. I

AFTER DELAY HEAT SPEED DE-ENERGIZED.

(bower rema ns energ zed dur ng cont nuous fan mode).

INDOOR BLOWER SWITCHES TO FAN "4

SPEED, EAC TERM, REMAINS ENERGIZED,

HUM TERM. ENERGIZES

WITH COMB. AIR INDUCER.

Page 34

JobName

JobLocation

JobNo.

City

Date

State

Installer

UnitModelNo.

SerialNo.

HeatingSection

ElectricalConnectionsTight?

SupplyVoltage

BlowerMotorAmps []

FuelType:NaturalGas?

FurnaceBtuInput

City

Technician

State

[]

Blower Motor H.P.

Gas Piping Connections

Tight & Leak-Tested?

LP/Propane Gas? []

Line Pressure

Regulator Pressure

Flue Connections Tight?

Combustion Gas Tested?

Fan Control Setting

(45 Seconds Fixed On)

Fan Control Off Setting

Filter Clean & Secure?

Thermostat

w.c. _Nat,: w.c. - LP/Propane

[] Proper Draft? []

[] 002 [] co

Temperature Rise

Calibrated? []

[] Vent Clear? []

Heat Anticipator Properly Set? [] Level? []

Page 35

Lennox International Inc G50Uh 24A 045 Users Manual

LENNOX Furnace/Heater, Gas Manual L0806179 LENNOX Furnace/Heater, Gas Owner's Manual, LENNOX Furnace/Heater, Gas installation guides

G50UH-48C-110 to the manual 74bf3324-cf3b-4d2b-aaf5-4cd643369a3c

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