LENNOX Furnace/Heater, Gas Manual L0806234

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

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Page Count: 66

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_ 2007 Lennox Industries Inc.

Dallas, Texas, USA

INSTALLATION

INSTRUCTIONS

G71MPP SERIES UNITS

GAS UNITS Technical

50&334M

03/2008 J LJ _,Publications

Litho U.S.A.

RETAIN THESE INSTRUCTIONS

FOR FUTURE REFERENCE

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

G71MPP Parts Arrangement ..................... 3

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

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

General ....................................... 6

Installation - Setting Equipment .................. 6

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

Duct System .................................. 13

Pipe & Fittings Specifications ................... 13

Vent Pipe Sizing Worksheet .................... 14

Vent Piping Guidelines ......................... 15

Joint Cementing Procedure ..................... 16

Venting Practices ............................. 17

Gas Piping ................................... 25

Electrical ..................................... 27

Integrated Control ............................. 33

Blower Motor Performance ..................... 40

Unit Start-Up ................................. 51

Gas Pressure Measurement .................... 52 ,

High Altitude Information ....................... 53

Other Unit Adjustments ........................ 54

Heating Sequence of Operation ................. 55

Service ...................................... 57

Ignition Control Diagnostic Codes ............... 59

Troubleshooting ............................... 60

Repair Parts List .............................. 66

Start-Up & Performance Check List .............. 66

AWARNING

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.

03/08

IIIHIININIIIIIIIIIIIIIIIIIIIIIIIIIIII Page 1

505,334M

IIIIIINIIIIIIIIIIIIIIIHIIIIIIIIIIIIIIIIIIIIIIII

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

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

a. 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.

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

c. Bottom return air.

d. Return air from both sides.

e. Bottom and one side return air.

See Blower Performance Tables for additional information.

Optional External Side Return Air Filter Kit (Upflow Only) is not

for use with the optional RAB Return Air Base.

,,_ A -_

,_v----- B -_D,.

AIR FLOW

9-9/16 (14)

2OPTIONAL

EXTERNAL

SIDE RETURN

AIR FILTER KIT

(Either Side)

5/8(16)

--J_- 314(19)

(1016)

11-5/8

(295) Right

9-3/4 (248)

Left

EXTERNAL

SIDE RETURN

AIR FILTER KIT

(Either Side)

SUPPLY AIR

OPENING

23-3/4 (603)

2 OPTIONAL I_ 25 (635)

TOP VIEW

5-1/2

(140) t

6-1/2

(1_5)

4-1/8 6-3/4

(103) (171)

1-3/4 (45) Right

3-9/16 (91) Left -I_

A 2-1/2 .__

(64)

I_ 28-1/2

J_ (724)

1.9_ 19-7/16_

r_ COMBUSTION AIR INTAKE

.... _ _ (Either Side)

( Iy\/EXHAUSTAIROUTLET

9- _/_ Av(Either Side)

GAsP,P,NG,NLET

_11_ y\ (Either Side)

\.r_CONDENSATE

L_TRAPCONNECTION

°Oo_ (Either Side)

_ ELECTRICAL INLET

_p_,ql__ - (Either side )

04- --

I23 _

18-3/4 (476) (102 (584) i

•1OPTIONAL 14

IRETURN CUTOUT (3.._6)

J (Either Side)

LUp-Flow Only

1-15/16 (49)

Jl.--c 4-

3/4 (19) 1Bottom Return 4-1/4 1 Bottom Return

Air Opening (108) Air Opening

FRONT VIEW SIDE VIEW

9/16

'q'- (14)

A B C

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

G71MPP-36B-070 17-1/2 446 16-3/8 416 16 406

G71MPP-36C-090

G71MPP-60C-090 21 533 19-7/8 454 19-1/2 495

G71MPP-60C-110

G71MPP-60D-135 24-1/2 622 23-3/8 546 23 584

Page 2

BAGASSEMBLIES

(shippinglocation)

HEATEXCHANGER

BURNERBOXASSEMBLY

VARIABLE CAPACITY

GAS VALVE

COMBUSTION AIR

PRESSURE

SWITCHES

VARIABLE SPEED

COMBUSTION AIRINDUCER

BURNER ACCESS PANEL

WARM HEADER

(COLLECTOR BOX)

CONDENSER COIL

PRESSURE SWITCH

ASSEMBLY WITH

PRESSURE

CONDITIONING

DEVICE

COLD HEADER

(COLLECTOR BOX)

SHIPPING BLOCK

(-135unitsonly)

BLOWER ACCESS PANEL

VARIABLE SPEED

BLOWER MOTOR

SIGHT GLASS TRANSFORMER INTEGRATED

CONTROL

FIGURE 1

Page 3

TheG71MPPgasfurnaceisequippedwithavariable-ca-

pacity,variable-speedintegratedcontrol.Thiscontrolen-

surescompatibilitywithLennox'HarmonyIII'" zonecon-

trol system,as well as a thermostatwhich provides

humiditycontrol.EachG71MPPisshippedreadyforinstal-

lationintheupflow,downflow,horizontalleftairdischarge

orhorizontalrightairdischargeposition.

Thefurnaceisequippedforinstallationinnaturalgasap-

plications.A conversionkit(orderedseparately)isrequired

foruseinpropane/LPgasapplications.

The G71MPP can be installed only as a Direct Vent gas

central furnace.

NOTE- In Direct Vent installations, combustion air is taken

from outdoors and flue gases are discharged outdoors.

See figure 2 for applications including roof termination.

DIRECT VENT INSTALLATION

EXHAUST OUTLET

COMBUSTION

AIR INTAKE

OUTSIDE OF

HOUSE

FIGURE 2

Package 1 of 1 contains

1 - Assembled G71MPP unit

1 - Bag assembly containing the following:

3 - Screws

3 - Wire nuts

1 - Snap bushing

1 - Snap plug

1 - Wire tie

1 - Condensate trap

1 - Condensate trap cap

2 -2" diameter vent /intake plugs

1 -3" diameter cabinet plug (intake)

NOTE- G71MPP-60C-110 units also include a 2" diameter

PVC street elbow, which is shipped on the blower deck in

the heating compartment. G71MPP-60D-135 units are

shipped with a 3" to 2" PVC reducing elbow.

Check equipment for shipping damage. If you find any

damage, immediately contact the last carrier.

The following items may also be ordered separately:

1- Thermostat

1 - Propane/LP changeover kit

DANGER

&WARNING

-&CAUTION

Use only the type of gas approved for use with this furnace.

Refer to unit nameplate.

G71MPP units are CSA International certified to ANSI

Z21.47 and CSA 2.3 standards.

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 (ANSl-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.

This furnace is CSA International certified for installation

clearances to combustible material as listed on the unit

nameplate and in the tables in figures 4, 9 and 13. Accessi-

bility and service clearances must take precedence over

fire protection clearances.

NOTE- For installation on combustible floors, the furnace

shall 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

Page 4

garage,hangar,orotherbuildingthathasahazardousat-

mosphere,thefurnacemustbeinstalledaccordingtorec-

ommendedgoodpracticerequirementsandcurrentNa-

tionalFuelGasCodeorCSAB149standard.

NOTE -Furnace must be adjusted to obtain a temperature

rise within the range specified on the unit nameplate. Fail-

ure to do so may cause erratic limit operation.

This G71MPP furnace may be used as a high-static unit

heater. The G71MPP may also be installed in an aircraft

hangar in accordance with the Standard for Aircraft Han-

gars (ANSI/NFPA No. 408-1990).

Installation in parking structures must be in accordance

with the Standard for Parking Structures (ANSI/NFPA No.

88A-1991 ). Installation in repair garages must be in accor-

dance with the Standard for Repair Garages (ANSI/NFPA

No. 88B-1991).

This G71MPP 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.

When installed, this furnace must be electrically grounded

according to local codes. In addition, in the United States,

installation must conform with the current National Electric

Code, ANSI/NFPA No. 70. The National Electric Code

(ANSI/NFPA No. 70) is available from the following ad-

dress:

National Fire Protection Association

1 Battery March Park

Quincy, MA 02269

In Canada, all electrical wiring and grounding for the unit

must be installed according to the current regulations of the

Canadian Electrical Code Part I (CSA Standard C22.1)

and/or local codes.

A CAUTION

The G71MPP furnace may be installed in alcoves, closets,

attics, basements, garages, and utility rooms.

This furnace design has not been CSA certified for installa-

tion in mobile homes, recreational vehicles, or outdoors.

Never use an open flame to test for gas leaks. Check all

connections using a commercially available soap solution

made specifically for leak detection.

Lennox does not recommend the use of G71MPP units as

a construction heater during any phase of construction.

Very low return air temperatures, harmful vapors and op-

eration of the unit with clogged or misplaced filters will dam-

age the unit.

G71MPP units may be used for heating of buildings or

structures 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

aflowed.

• 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 inputrate and temperature rise mustbe setperthe

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.

• The furnace heat exchanger, components, duct sys-

tem, 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 a licensedplumb-

er or gas fitter only.

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

• When a furnace is installed in an attic, the passage-

way to and service area surrounding the equipment

shall be floored.

Page 5

,-& WARNING

In addition to the requirements outlined previously, the fol-

lowing general recommendations must be considered

when installing a G71MPP 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.

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

lated space, keep insulation away from the furnace.

• When the furnace is installed in an unconditioned

space, consider provisions required to prevent freezing

of condensate drain system.

I-&WARNING I

,&,CAUTION

These instructions are intended as a general guide and do

not supersede local codes in any way. Consult authorities

having jurisdiction before installation.

UPFLOW APPLICATION

t1"

AIR FLOW

FRONT VIEW

UNIT

FRONT

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,

condensate trap and drain connections, and installation

and service clearances [24 inches (610 mm) at unit front].

The unit must be level from side to side. The unit may be

tilted slightly (maximum 1/2 in.) from back to front to aid in

the draining of the heat exchanger. See figure 3.

SETTING EQUIPMENT

UNIT MUST BE LEVEL SIDE-TO-SIDE IN ALL APPLICATIONS.

HORIZONTAL APPLICATION

SIDE VIEW

UNIT

FRONT

112"

max.

FRONT VIEW

1/2"

I rflax,

UNIT

FRONT

EN D VIEW

UNIT MAY BE TILTED SLIGHTLY (MAX. 1/2") FROM BACK TO FRONT

TO AID IN THE DRAINING OF THE HEAT EXCHANGER.

DOWNFLOW APPLICATION

AIR FLOW

FRONT VIEW

1/2"

rflax.

SIDE VIEW

FIGURE 3

Page 6

NOTE -G71MPP-36B and -36C units with 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 washer (rather than the rubber mounting

grommet used with a flexible mounting leg), The bolt and

washer must be removed before the furnace is placed

into operation. After the bolt and washer have been re-

moved, the rigid leg will not touch the blower housing.

NOTE -G71MPP-60D-135 units are equipped with a ship-

ping pad under the blower housing. Remove the shipping

pad prior to operation.

Allow for clearances to combustible materials as indicated

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

cove installations are shown in figures 4, 9 and 13,

WARNING

Upflow Applications

The G71MPP gas furnace can be installed as shipped in

the upfiow position, Refer to figure 4 for clearances,

Installation Clearances

Top

Left Side . _ Right Side

Bottom (Floor)

Top/Plenum 1 in. (25 ram)

*Front 0

Back 0

Sides 0-_

Vent 0

Floor 05

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

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

tAllow proper clearances to accommodate condensate trap and

vent pipe installation.

SFor installations on a combustible floor, do not install the fur-

nace directly on carpeting, tile or other combustible materials oth-

er than wood flooring.

FIGURE 4

Return Air -- Upflow Units

Return air can be brought in through the bottom or either

side of the furnace installed in an upfiow 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 20x25x I in. (508x 635x 25 ram) air filter.

(Required to maintain proper air velocity.) See figure 5.

Page 7

2 - Return air from single side with optional RAB Return

Air Base. See figure 7.

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)

20" X 25" X 1"

(508mm X635mm X 25mm)

Air Filter

Return

Air

Plenum

FIGURE 5

G71MPP applications which include side return air and

a condensate trap installed on the same side of the

cabinet require either a return air base or field-fabri-

cated transition to accommodate an optional IAQ ac-

cessory taller than 14.5'"

Removing the 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 6.

Screw,/

Bottom

FIGURE 6

Optional Return Air Base

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

Removing the Bottom Panel

Cap

(356)

r 123(584) ---_-_

Overall

(Maximum) 1Minimu_ I

I11(279) I

2Maximum I

' 1 Unit sidereturn 14_56) i

I air opening

FURNACE

FRONT

5-5/8 SIDE RETURN AIR

(143) OPENINGS

_.t (Either Side)

-- 23 (584)OPTIONAL RAB

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

21 (533) RAB-C (98M58) -I_ 27-5/8 (702) --I1,-

24-1/2 (622) RAB-D (98M59) 7/8

FRONT VIEW (22) SIDE VIEW

122-7-16

(570)

Overall

(Maximum)

-T

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 ram).

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 7

Page 8

SettinganUpflowUnit

Whenthesidereturnairinletsareusedinanupflowap-

plication,itmaybenecessarytoinstallshimsonthebottom

ofthefurnace.Ifdesired,usefield-suppliedcorrosion-re-

sistant5/16inchmachinebolts(4)andnuts(8)tolevelthe

furnace,Seefigure8,

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

1 - Lay 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 8 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

flat 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

Furnace Front _¢

3/8 1-3/4

(44)

1-3/4

(44)

Leveling Bolt

Locati,

Furnace

Bottom

Leveling Bolt

Locations

3/8

(10)

3/8 1-3/4

(10) (44)

I-3/4 (44)

FIGURE 8

Downflow Applications

The unit may be installed three ways in downflow applica-

tions: on non-combustible flooring, on combustible flooring

using an additive base, or on a reverse-flow cooling coil

cabinet. Do not drag the unit across the floor in the

downflow position. Flange damage will result.

Refer to figure 9 for clearances in downflow applica-

tions.

Downflow Application Installation Clearances

Top

Left Side _ Right Side

Boffom

Top 0

*Front 0

Back 0

Sides 0t

Vent 0

Floor NC$

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

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

tAllow proper clearances to accommodate condensate trap and

vent pipe installation.

SThe furnace may be installed on a combustible wood floor if an

optional additive base is installed between the furnace and the

combustible floor.

FIGURE 9

Installation on Non-Combustible Flooring

1 - Cut floor opening keeping in mind clearances listed on

unit rating plate. Also keep in mind gas supply connec-

tions, electrical supply, flue and air intake connections

and sufficient installation and servicing clearances,

See table 1 for correct floor opening size.

2 - Flange warm air plenum and lower the plenum into the

opening.

3 - Set the unit over the plenum and seal the plenum to

the unit,

4 - Ensure that the seal is adequate,

TABLE 1

NON-COMBUSTIBLE FLOOR

Front to Rear

Model No.

B Cabinet (17.5") 502

C Cabinet(21") 502

D Cabinet(24.5") 502

in.

19 - 3/4

)PENING SIZE

Side to Side

in. mm

16 - 5/8 422

20-1/8 511

23 - 5/8 600

NOTE -Floor opening dimensions listed are 1/4 inch (6 mm) larger than

the unit opening. See dimension drawing on page 2.

Page 9

Installation on Combustible Flooring

(Using an Additive Base)

1 - When unit is installed on a combustible floor, an addi-

tive base must be installed between the furnace and

the floor, The base must be ordered separately. See

table 2 for opening size to cut in floor.

Ak CAUTION

TABLE 2

ADDITIVE BASE FLOOR OPENING SIZE

Cabinet

Width

B Cabinet

(17.5")

C Cabinet

(21")

D Cabinet

(24.5")

Catalog

Number

11M60

11M61

11M62

Frontto Rear

in. mm

22 559

Side to Side

in. mm

18 - 3/4 476

22 - 3/4 578

25 - 3/4 654

G71MPP UNIT_ __T

SUPPLY AIR PLENUM

PROPERLY R ,VEBASE

FIGURE 10

2 - After opening is cut, set additive base into opening.

3 - Check fiberglass strips on additive base to make sure

they are properly glued and positioned,

4 - Lower supply air plenum into additive base until ple-

num flanges seal against fiberglass strips.

NOTE -Be careful not to damage fiberglass strips,

Check for a tight seal.

5 - Set the furnace over the plenum,

6 - Ensure that the seal between the furnace and plenum

is adequate.

Installation on Cooling Coil Cabinet

1 - Refer to reverse-flow coil installation instructions for

correctly sized opening in floor and installation of cabi-

net,

2 - When cooling cabinet is in place, set and secure the

furnace according to the instructions that are provided

with the cooling coil, Secure the furnace to the cabinet,

3 - Seal the cabinet and check for air leaks,

Return Air Opening -- Downflow Units

Return air may be brought in only through the top opening

of a furnace installed in the downflow position.The follow-

ing steps should be taken when installing plenum:

1 - Bottom edge of plenum should be flanged with a

hemmed edge (See figure 11 or 12).

2 - Sealing strips should be used to ensure an airtight seal

between the cabinet and the plenum.

3 - In all cases, plenum should be secured to top of fur-

nace using sheet metal screws,

4 - Make certain that an adequate seal is made,

PLENUM --*.._ I"'t'_ "_

(Field Provided) _ SECURE FROM

•_L_UTSIDE CABINET

/vII J CABINET

SEALING STRIP _ II./SIDE PANEL

(Field Provided) ...... II

Side View II

FIGURE 11

PLENUM

(Field Provided_-._

SECURE FROM

INSIDE CABINET Side View

SEALING STRIP

,_/.J.Field Provided)

/CABINET

, SIDE PANEL

FIGURE 12

Page 10

Horizontal Applications

The G71MPP furnace can be installed in horizontal ap-

plications with either right- or left-hand air discharge,

The G71MPP may also be installed as a unit heater. Either

suspend the furnace as shown in figure 14, or install the fur-

nace on a field-fabricated raised platform. The unit must be

supported at both ends and beneath the blower deck to

prevent sagging,

Refer to figure 13 for clearances in horizontal applications,

Horizontal Application

Installation Clearances

Left End

Air

Flow

Right-Hand Discharge

Top

)/Right End

_Air

• Flow

Bottom (Floor)**

Left End

Air

Flow

Left-Hand Discharge

Top

Bottom (Floor)**

Right End

Air

Flow

Top 6

Front* 6

Back 6

Ends 6

Vent 6

Floor 65

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

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

**A 5-1/2" service clearance must be maintained below the unit to

provide for servicing of the condensate trap.

:_For installations on a combustible floor, do not install the fur-

nace directly on carpeting, tile or other combustible materials oth-

er than wood flooring.

FIGURE 13

Suspended Installation of Horizontal Unit

NOTE- If unit is suspended, horizontal support kit (Cat No.

56J18 ordered separately) or equivalent is recommended

to ensure proper unit support and coil drainage.

1 - Select location for unit keeping in mind service and

other necessary clearances. See figure 13,

2 - Provide service platform in front of unit,

3 - If unit is installed above finished space, fabricate a

drain pan fitted with a 1/2 inch or 3/4 inch N,P,T, fitting,

4 - Using 3/8 inch rods and support frame kit or field-fabri-

cated supports, fabricate suspension hangers, keep-

ing in mind front service access clearances.

5 - Mount unit on support frame as shown in figure 14,

6- Continue with exhaust, condensate and intake line

piping instructions,

TYPICAL HORIZONTAL APPLICATION

BLOWER ACCESS 3/8 in. RODS

PANEL l

CONNECTION

DRAIN PAN

SUPPORT FRAME (to protect finished space)

FIGURE 14

If unit is suspended above finished space, hang the

field-provided drain pan below the support frame as

shown in figure 14. Leave 5-1/2 inches for service

clearance below unit for condensate trap,

Route auxiliary drain line so that water draining from

this outlet will be easily noticed by the homeowner, If

necessary, run the condensate line into a condensate

pump to meet drain line slope requirements, The

pump must be rated for use with condensing furnaces,

Protect the condensate discharge line from the pump

to the outside to avoid freezing.

Platform Installation of Horizontal Unit

Select location for unit keeping in mind service and

other necessary clearances, See figure 13,

Construct a raised wooden frame and cover frame

with a plywood sheet, Provide a service platform in

front of unit, If unit is installed above finished space,

fabricate a drain pan to be installed under unit.

When installing the unit in a crawl space, a proper sup-

port platform may be created using cement blocks and

the horizontal support frame kit (ordered separately,

Page 11

Lennoxpart number56J18).Positionthe support

frameontopoftheblocksandinstalltheunitonthe

frame.Leave5-1/2inchesfor serviceclearancefor

condensatetrap.

INTAKE

*Gas connector may be

used for Canadian

installation ff accept-

able by local authority

having jurisdiction.

EXHAUST PIPE

*GAS

CONNECTOR

RAISED

CONDENSATE

LINE SERVICE PLATFORM

FIGURE 15

3 - Route auxiliary drain line so that water draining from

this outlet will be easily noticed by the homeowner. If

necessary, run the condensate line into a condensate

pump to meet drain line slope requirements. The

pump must be rated for use with condensing furnaces.

Protect the condensate discharge line from the pump

to the outside to avoid freezing.

4 - Set unit in drain pan as shown in figure 15. Leave 5-1/2

inches for service clearance below unit for condensate

trap.

5 - Continue with exhaust, condensate and intake piping

installation according to instructions.

G71MPP Installed in Unit Heater Applications

Horizontal unit heaters may be installed either suspended

from the ceiling using the support frame kit or mounted on a

field-fabricated raised platform. The condensate trap must

be installed where it can be serviced at a later date.

The G71MPP may also be installed as a unit heater. Either

suspend the furnace from roof rafters or floor joists, as

shown in figure 14, or install the furnace on a field-fabri-

cated raised platform, as shown in figure 15. The unit must

be supported at both ends and beneath the blower deck to

prevent sagging.

Unit Heater Discharge Duct Guidelines

A field-fabricated and installed discharge air duct and grille

cabinet is suitable for use with the G71MPP heater. See fig-

ure 16, Keep the following items in mind when constructing

the cabinet,

1 - Outer dimensions of cabinet should match those of the

unit heater, so the duct/grille cabinet installs flush with

the unit heater cabinet. See figure 16.

2 - Flange both ends of duct/grille cabinet so that screws

can be used to secure cabinet to discharge end of unit

heater.

3- To ensure proper operation, the duct/grille cabinet

must be at least 18 inches long.

4 - Use #10-16 x 1/2 inch sheet metal screws to secure

duct/grille cabinet to unit, taking care not to damage in-

ternal components of unit heater when drilling holes or

installing screws. See figure 16,

5 - Use adjustable, double-deflection grille(s) to distribute

discharge air, Adjust static pressure to be in the 0.06

inch to 0.10 inch w.c. range.

DRAIN PA_

NOTE _Wtlen installing duct/grille cabinet, take care not to damage internal unit

beater components wben drilling boles or installing screws.

FIGURE 16

Return Air -- Horizontal Applications

Return air may be brought in only through the end of a fur-

nace installed in the horizontal position. The furnace is

equipped with a removable bottom panel to facilitate instal-

lation. See figure 6.

This unit is not equipped with a filter or rack, A field-pro-

vided filter is required for the unit to operate properly. Table

3 lists recommended filter sizes,

A filter must be in place whenever the unit is operating.

NOTE -In upflow applications where side return air fil-

ter is installed on same side as the condensate trap, fil-

ter rack must be installed beyond condensate trap to

avoid interference.

TABLE 3

Furnace

Cabinet Width

B Cabinet (17-1/2")

C Cabinet (21")

D Cabinet (24-1/2")

Filter Size

Side Return Bottom Return

16X25Xl(1) 16X25Xl(1)

16X25Xl(1) 20X25Xl(1)

16X25Xl(2) 24X25Xl(1)

Page 12

Useindustry-approvedstandardsto sizeandinstallthe

supplyandreturnairductsystem.Thiswillresultinaquiet

andlow-staticsystemthathasuniformairdistribution.

NOTE -Operation of this furnace in heating mode (indoor

blower operating at selected heating speed) with an exter-

nal static pressure which exceeds O.8 inches w.c. may re-

sult in erratic limit operation.

Supply Air Plenum

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

access panel should be installed in the supply air duct. The

access panel should be large enough to permit inspection

(by reflected light) of the heat exchanger for leaks after the

furnace is installed. If present, this access panel must al-

ways be in place when the furnace is operating and it must

not allow leaks into the supply air duct system.

Return Air Plenum

Return air must not be drawn from a room 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 appliance

is operating in a room with negative pressure, the flue prod-

ucts can be pulled back down the vent pipe and into the

room. This reverse flow of the flue gas may result in incom-

plete combustion and the formation of carbon monoxide

gas. This toxic gas might then be distributed throughout the

house by the furnace duct system.

Return air can be brought in through the bottom or either

side of the furnace. If a furnace 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 equivalent sealing method between the

plenum and the furnace cabinet to ensure a tight seal. If a

filter is installed, size the return air duct to fit the filter frame.

All pipe, fittings, primer and solvent cement must conform

with American National Standard Institute and the Ameri-

can Society for Testing and Materials (ANSI/ASTM) stan-

dards. The solvent shall be free flowing and contain no

lumps, undissolved particles or any foreign matter that ad-

versely affects the joint strength or chemical resistance of

the cement. The cement shall show no gelation, stratifica-

tion, or separation that cannot be removed by stirring. Re-

fer to table 4 for approved piping and fitting materials.

TABLE 4

PIPING AND FITTINGS SPECIFICATIONS

ASTM

PIPE & FITTING MATERIAL SPECIFICATION

Schedule 40 PVC (Pipe) D1785

Schedule 40 PVC (Cellular Core Pipe) F891

Schedule 40 PVC (Fittings) D2466

Schedule 40 CPVC (Pipe) F441

Schedule 40 CPVC (Fittings) F438

SDR-21 PVC or SDR-26 PVC (Pipe) D2241

SDR-21 CPVC or SDR-26 CPVC (Pipe) F442

Schedule 40 ABS Cellular Core DWV (Pipe) F628

Schedule 40 ABS (Pipe) D1527

Schedule 40 ABS (Fittings) D2468

ABS-DWV (Drain Waste & Vent) D2661

(Pipe & Fittings)

PVC-DWV (Drain Waste & Vent) D2665

Pipe & Fittings)

_ CAUTION

Use PVC solvent cement as specified in ASTM D2564 and

ABS solvent cement as specified in ASTM D2235. Primers

and solvents must meet ASTM specifications. PVC primer

is specified in ASTM F 656. As an alternate, use all purpose

cement, as specified in ASTM performance requirements

D-2564, D-2235 and F493 to bond ABS, PVC, or CPVC

pipe when using fittings and pipe made dthe same materi-

als. Use transition solvent cement when bonding ABS to ei-

ther PVC or CPVC. Low temperature solvent cement is rec-

ommended. Metal or plastic strapping may be used for vent

pipe hangers.

Uniformly apply a liberal coat of PVC primer for PVC or use

a clean dry cloth for ABS to clean inside socket surface of

fitting and male end dpipe to depth of fitting socket. Refer

to the procedure specified in ASTM D3138.

Canadian Applications Only -Pipe, fittings, primer and

solvent cement used to vent (exhaust) this appliance must

be certified to ULC S636 and supplied by a single

manufacturer as part of an approved vent (exhaust) sys-

tem. When bonding the vent system to the furnace, use

ULC$636 approved One-Step Transition Cement to bond

the pipe to the flue collar, or to bond the 90 °elbow or re-

ducing 90°elbow to the flue collar. In addition, the first

three feet of vent pipe from the furnace flue collar must be

accessible for inspection.

Table 5 lists the available exhaust termination kits, as well

as vent pipe equivalencies which must be used when sizing

vent pipe. All Lennox vent terminations are PVC.

Page 13

TABLE 5

OUTDOOR TERMINATION KITS AND CORRESPONDING EQUIVALENCIES

Vent Pipe Length Equivalency (feet)

Outdoor Ex- Outdoor Ex-

VENT haust Accel- haust Accel- 1-112" 2" Con- 3" Con- 2" Wall Plate 3" Wall 2" Wall

UNIT PIPE erator erator Concentric centric Kit centric Kit Kit Plate Kit Ring Kit

MODEL DIA. (Dia. X (Dia. X Kit

(in.) Length) Length)

22G44 44J40

1-1/2" X 12" 2"X 12" 71M80 69M29 60L46 30G28 81J20 15F74

2 4 Not 12 Not Not 4 4* 4

Allowed Allowed Allowed

2-1/2 5 Not 15 Not Not 5 5* 5

Allowed Allowed Allowed

36B-070

3 8 Not 24 Not Not 8 8* 8

Allowed Allowed Allowed

4 14 Not 42 Not Not 14 14" 14

Allowed Allowed Allowed

2 Not 1 Not 3 3 Not 1 1"*

Allowed Allowed Allowed

2-1/2 Not 2 Not 6 6 Not 2 2**

Allowed Allowed Allowed

60C-090 3 Not 2 Not 6 6 Not 2 2**

Allowed Allowed Allowed

4 Not 4 Not 12 12 Not 4 4**

Allowed Allowed Allowed

2-1/2 Not 2 Not 6 6 Not 2 2

Allowed Allowed Allowed

60C-110 3 Not 2 Not 6 6 Not 2 2

Allowed Allowed Allowed

4 Not 4 Not 12 12 Not 4 4

Allowed Allowed Allowed

Not

3 Not 6 Not Not 15 Not 6

Allowed Allowed Allowed Allowed Allowed

60D-135

4 Not 10 Not

Allowed Allowed

*Requires field-provided and installed 1-1/2" exhaust accelerator.

Not

Not 25 Not 10

Allowed Allowed Allowed

**Requires field-provided and installed 2" exhaust accelerator.

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Proposed vent pipe size :

Termination kit catalog number :

Vent pipe equivalency value from table 5 :

Total number of 90 ° elbows required (indoors and outdoors)

X 5 = equivalent feet of pipe

Total number of 45 ° elbows required (indoors and outdoors)

X 2.5 = equivalent feet of pipe

Linear feet of straight pipe required :

Add equivalent feet of vent pipe listed in

steps 2 through 5.

Equivalent Feet

TOTAL

If the total is equal to, or less than, the allowable maximum given in table 7, the proposed pipe size is acceptable. If the

total exceeds the maximum allowed vent pipe length, repeat the process above using the next larger diameter pipe until

an acceptable total is achieved.

NOTE -In Direct Vent systems, total the equivalent length of either the exhaust OR intake piping run, depending upon which

will be LONGER. Intake and exhaust pipe diameter must be the same size and must be terminated in the same pressure

zone. Intake and exhaust pipe should be roughly the same length.

Page 14

The G71MPP can be installed only as a Direct Vent gas

central furnace.

NOTE- In Direct Vent installations, combustion air is taken

from outdoors and flue gases are discharged outdoors.

Intake and exhaust pipe sizing -- Size pipe according to

tables 6 and 7. Table 6 lists the minimum equivalent vent

pipe lengths permitted. Table 7 lists the maximum equiva-

lent pipe lengths permitted.

Maximum vent length is defined as:

Total length (linear feet) of pipe,

Plus Equivalent length (feet) of fittings,

Plus Equivalent length (feet) of termination.

NOTE- Include ALL pipe and ALL fittings, both indoors

and outdoors. Measure equivalent length of intake and

exhaust pipe separately. Use the greater of the two

lengths to determine vent pipe diameter to be used for

both intake and exhaust.

Regardless of the diameter of pipe used, the standard roof

and wall terminations described in section Exhaust Piping

Terminations should be used. Exhaust vent termination

pipe is sized to optimize the velocity of the exhaust gas as it

exits the termination, Refer to table 8,

NOTE- The exhaust pipe should be offset a minimum of 12

inches to avoid the possibility of water droplets being re-

leased from the exhaust termination, The minimum ex-

haust vent length is 15 ft, Shorter exhaust vent lengths may

result in the discharge of water droplets from the exhaust

termination, in spite of the 12-inch vertical offset. See figure

17,

Each 90° elbow (including those provided with the furnace)

of any diameter is equivalent to 5 feet (1,52m) of vent pipe

of the same diameter. Two 45° elbows are equivalent to

one 90° elbow of the same diameter, One 45° elbow is

equal to 2,5 feet (.76m) dvent pipe of the same diameter.

In some applications which permit the use of several differ-

ent sizes of vent pipe, a combination vent pipe may be

used. Contact Lennox' Application Department for assis-

tance in sizing vent pipe in these applications.

Exhaust Pipe Offset

_'q 12" Min. t1_

Upflow and Downflow Application

Rooftop Termination

"br"

12" Min. "1_1

Horizontal Application

Rooftop Termination I

Upflow and Downflow Application

Side Wall Termination

_1- 12" Min. -I_

Horizontal Application

Side Wall Termination

FIGURE 17

Page 15

NOTE -The flue collar on all models is sized to accommo-

date 2" Schedule 40 flue pipe, When vent pipe which is

larger than 2" must be used in an upflow application, a 2"

elbow must be applied at the flue collar in order to properly

transition to the larger diameter flue pipe. This elbow must

be added to the elbow count used to determine acceptable

vent lengths. Assign an equivalent feet value to this elbow.

Contact the Application Department for more information

concerning sizing of vent systems which include multiple

pipe sizes.

Use the following steps to correctly size vent pipe diameter,

Refer to Vent Pipe Size Determination Worksheet on

page 65.

1 - Determine the vent termination and its corresponding

equivalent feet value according to table 5,

2 - Determine the number of 90° elbows required for both

indoor and outdoor (e,g. snow riser) use. Calculate the

corresponding equivalent feet of vent pipe.

3 - Determine the number of 45° elbows required for both

indoor and outdoor use, Calculate the corresponding

equivalent feet of vent pipe,

4 - Determine the length of straight pipe required,

5- Add the total equivalent feet calculated in steps 1

through 4 and compare that length to the maximum

values given in table 7 for the proposed vent pipe di-

ameter. If more than one diameter of pipe is being

used, use the appropriate value from table 7 for the

larger sized pipe, If the total equivalent length required

exceeds the maximum equivalent length listed in the

appropriate table, evaluate the next larger size pipe.

AIMPORTANT

TABLE 6

MINIMUM VENT PIPE LENGTHS

G71MPP

MODEL

070,090

110"*

MIN. EQUIV.

VENT LENGTH

15 ft.*

135"**

*Any approved termination ma

length listed.

EXAMPLE

5 ft. plus 2 elbows of 2", 2-1/2", 3"

or 4" diameter pipe

5 ft. plus 2 elbows of 2-1/2" 3" or 4"

diameter pipe

5 ft, plus 2 elbows of 3" or 4"

diameter pipe

, be added to the minimum equivalent

**G71MPP-60C-110 must have 90 °street eli (suppfied) installed directly

into unit flue collar.

***G71MPP-60D-135 must have 3" to 2" reducing eli (supplied) installed

directly into unit flue collar.

TABLE 7

MAXIMUM VENT PIPE LENGTHS

MAXIMUM EQUIVALENT VENT

G71MPP LENGTH FEET

ALTITUDE MODEL 2" 2-1/2" 3" 4"

PIPE PIPE PiPE PiPE

070 75 135 150 250

0 - 7500 090 50 100 125 225

(0 - 2286 m) 110" 20 60 125 200

135"* n/a n/a 125 180

070 60 125 150 250

7501 - 10000 090 25 60 125 225

(2287 - 3048 m) 110" n/a 40 90 200

135"* n/a n/a 70 180

n/a -- Not allowed.

*G71MPP-60C-110 must have 90 °street eli (supplied) installed directly

into unit flue collar.

**G 71MPP-60D-135 must have 3" to 2" reducing eli (supplied) installed

directly into unit flue collar.

NOTE -Elbows and pipe required for vent terminations must be added

when calculating equivalent vent length.

All cementing of joints should be done according to the

specifications outlined in ASTM D 2855.

,& DANGER

1 - Measure and cut vent pipe to desired length,

2 - Debur and chamfer end of pipe, removing any ridges

or rough edges, If end is not chamfered, edge of pipe

may remove cement from fitting socket and result in a

leaking joint,

3 - Clean and dry surfaces to be joined,

4- Test fit joint and mark depth of fitting on outside of

pipe,

5 - Uniformly apply a liberal coat of PVC primer for PVC or

use a clean dry cloth for ABS to clean inside socket

surface of fitting and male end of pipe to depth of fitting

socket,

NOTE -Furnace flue collar and air inlet fitting are both

made of ABS material. Use transition solvent cement

when joining ABS fittings to PVC pipe,

6 - Promptly apply solvent cement to end of pipe and in-

side socket surface of fitting. Cement should be ap-

plied lightly but uniformly to inside of socket, Take care

to keep excess cement out of socket, Apply second

coat to end of pipe,

NOTE- Time is critical at this stage. Do not allow prim-

er to dry before applying cement.

Page 16

7- Immediatelyafterapplyinglastcoatofcementtopipe,

andwhilebothinsidesocketsurfaceandendofpipe

arewetwithcement,forcefullyinsertendofpipeinto

socketuntilitbottomsout.TurnPVCpipe1/4turndur-

ingassembly(butnotafterpipeisfullyinserted)todis-

tributecementevenly.DONOTturnABSorcellular

corepipe.

NOTE -Assembly should be completed within 20 sec-

onds after last appfication of cement. Hammer blows

should not be used when inserting pipe.

8 - After assembly, wipe excess cement from pipe at end

of fitting socket. A properly made joint will show a bead

around its entire perimeter. Any gaps may indicate a

defective assembly due to insufficient solvent.

9 - Handle joints carefully until completely set.

The thickness of construction through which vent pipes

may be installed is 24" (610mm) maximum and 3/4"

(19mm) minimum. If a G71MPP furnace replaces a furnace

which was commonly vented with another gas appliance,

the size dthe existing vent pipe for that gas appliance must

be checked. Without the heat of the original furnace flue

products, the existing vent pipe is probably oversized for

the single water heater or other appliance. The vent should

be checked for proper draw with the remaining appliance.

1 - Use recommended piping materials for exhaust pip-

ing.

2 - Secure all joints so that they are gas-tight using ap-

proved cement.

Suspend piping using hangers at a minimum of every

5 feet (1.52m) for sched-

ule 40 PVC and every 3

feet (.91m) for ABS-DWV,

PVC-DWV, SPR-21 PVC,

and SDR-26 PVC piping.

A suitable hanger can be

fabricated by using metal

or plastic strapping or a

large wire tie.

STRAPPING

(metal, plastic

large wire

ties)

FIGURE 18

3- In areas where piping penetrates joists or interior

walls, hole must be large enough to allow clearance on

all sides of pipe through center of hole using a hanger.

4 - Isolate piping at the point where it exits the outside wall

or roof in order to prevent transmission of vibration to

the structure.

5 - When furnace is installed in a residence where unit is

shut down for an extended period of time, such as a

vacation home, make provisions for draining conden-

sate collection trap and lines.

Exhaust Piping (Figures 19 and 20)

NOTE- A 2" diameter PVC street ell is located on the blow-

er deck of 60C-110 units, Street ell must be_glued using

transition solvent cement directly into the unit flue collar.

See figure 19. A 3"to 2" PVC reducing ell is located on the

blower deck of the 60D-135 units, In upflow or downflow

applications, the reducing ell must be glued using transi-

tion solvent cement directly into the unit flue collar.

1 - Choose the appropriate side for venting in upflow or

downflow positions, Exhaust piping exits from the top

of the unit in horizontal air discharge applications.

Glue the field-provided exhaust vent pipe (or provided

street ell or reducing ell in upflow or downflow applica-

tions) to the flue collar, All PVC cement joints should

be made according to the specifications outlined in

ASTM D 2855. Refer to pipe and fittings specifications

and gluing procedures,

A, IMPORTANT

2 - All horizontal runs of exhaust pipe must slope back to-

ward unit. A minimum of 1/4" (6mm) drop for each 12"

(305mm) of horizontal run is mandatory for drainage.

Horizontal runs of exhaust piping must be supported

every 5 feet (1,52m) using hangers.

NOTE -Exhaust piping should be checked carefully to

make sure there are no sags or low spots.

3 - On the opposite side of the cabinet, glue the provided

2" vent plug into the unused flue collar,

4- Route piping to outside of structure, Continue with

installation following instructions given in piping ter-

mination section.

A, CAUTION

Ak CAUTION

Page 17

PLUG

VENT PLUG

(Must be

glued in

place)

PLUG

TYPICAL EXHAUST PIPE CONNECTIONS AND CONDENSATE TRAP INSTALLATION

IN UPFLOW OR DOWNFLOW DIRECT VENT APPLICATIONS

(Right-Hand Exit in Upflow Application Shown) 45°

MAX

2-1/2",

3", OR

TRANSiTiON

G71 MPP-070,

2" or -090 with SIDE ViEW

2-1/2", 3", or4"

vent pipe

CONDENSATE

TRAP

(Must be installed

on same side as

exhaust piping)

"2" diameter street elbow provided.

**3" to 2" diameter reducing elbow provided.

*** Max 2" pipe length between reducing

elbow and transition when 4" pipe is used.

TYPICAL EXHAUST PIPE CONNECTIONS

HORIZONTAL DIRECT VENT APPLICATIONS

(Horizontal Right-Hand Air Discharge Application Shown)

*2" maximum length -36B-070

-36C-090

for -135 only. -60C-090

.60C.110"

.60D-135"

TRANSiTiON

DO NOT transition from

smaller to larger pipe

size in horizontal runs.

-36B-070

,,1"36C'090

-60C-090

45 °

MAX

2-1/2", p:>_]

3":4OR _ TRANSmON

(use only if 4"

TRANSITION _ pipe is

required)

Ft /2 ....

G71MPP-110 with

2-1/2", 3", OR 4" G71MPP-135 with

vent pipe 3" OR 4" vent pipe

FIGURE 19

Intake Piping

The G71MPP furnace may be installed only in direct vent

applications,

The G71MPP unit is designed for either left-side or right-

side air intake connections in either upflow or downflow ap-

plications. In horizontal applications, air intake must be

brought in through the top, Intake air piping is independent

of exhaust piping,

FIGURE 20

Page 18

TYPICAL AIR INTAKE PIPE CONNECTIONS

UPFLOW OR DOWNFLOW DIRECT VENT APPLICATIONS

(Right-Hand Exit in Upfiow Application Shown)

PLUG

(Must be

glued in

place)

-36B-070

-36C-090

-60C-090

2-1/2", [:_

3" OR

TRANSITION [_2" TRANSITION

-36B-070

-36C-090

-60C-090

-60C-110

*Limit pipe length to 4" in

G 71MPP-135 applications.

-36B-070

-36C-090

-60C-090

-60C-110

-60D-135"

FIGURE 21

TYPICAL AIR INTAKE PIPE CONNECTIONS

HORIZONTAL DIRECT VENT APPLICATIONS

(Horizontal Right-Hand Air Discharge Application Shown)

*Limit pipe -36B-070

-36C-090

length to 4" in -60C-090

-135 applications. -60C-110

-60D-135"

-36B-070

-36C-090

-60C-090

-60C-110

TRANSITION

2"*

2-1/2",

3" OR 4"

-36B-070

-36C-090

-60C-090 2,,L_

FIGURE 22

Page 19

VENT TERMINATION CLEARANCES

FOR INSTALLATIONS IN THE USA AND CANADA*

[] - G71MPP VENT TERMINATION

O - AIR INLET OF OTHER APPLIANCE

A - Clearance above grade - 12 in. (305mm) minimum.

B - Clearance to window or door that may be opened -

for vent installations in USA- 12 in (305mm) minimum.

for vent installations in Canada - 12 in. (305mm) mini-

mum for appliances _ 100,000 Btuh (30 kW);

36 in (09m) minimum for appliances > 100,000 Btuh (30

kW)

C - Do not position terminations directly under roof eaves.

D - Clearance to electric meters, gas meters, regulators, and

refief equipm ent -

for vent installations in USA -48 in (1219mm) minimum.

for vent installations in Canada - see current edition of

CSA B149 Code

E - Clearance to non-mechanical air supply inlet or outlet

for vent installations in USA -48 in. (1219mm) minimum

horizontal and below, 12 in, (305ram) minimum above.

for vent installations in Canada - 12 in. (305mm) mini-

mum for appliances _ 100,000 Btuh (30 kW);

36 in, (0.9m) minimum for appliances > 100,000 Btuh (30

kW).

F - Clearance to mechanical air supply inlet --

for vent installations in USA - 36 in. minimum (914mm).

G - Clearance to mechanical air supply inlet --

for vent installations in Canada - 72 in. (1829mm) mini-

mum.

H - Do notpoint terminations into recessed areas such as win-

dow wells, stairwells or alcoves.

J - Do not position terminations directly above a pubfic walk-

way.

* Note -

(I) Dimensions are from the current edition of The National Fuel Gas Code - ANSI-Z22& 1/NFPA 54 for USA installa-

tions. In Canada, refer to current edition of CSA B149 installation codes. Local codes or regulations may require different

clearances.

(11)In Non-Direct Vent installations, combustion air is taken from indoors and the flue gases are discharged to the outdoors.

FIGURE 23

Page 20

Details of Intake and Exhaust Piping Terminations for

Direct Vent Installations

NOTE- In Direct Vent installations, combustion air is taken

from outdoors and flue gases are discharged to outdoors.

Intake and exhaust pipes may be routed either horizontally

through an outside wall or vertically through the roof. In at-

tic or closet installations, vertical termination through the

roof is preferred. Figures 24 through 32 show typical ter-

minations.

1 - Exhaust and intake exits must be in same pressure

zone. Do not exit one through the roof and one on the

side. Also, do not exit the intake on one side and the

exhaust on another side of the house or structure.

2 - Intake and exhaust pipes should be placed as close

together as possible at termination end (refer to il-

lustrations). Maximum separation is 3" (76mm) on roof

terminations and 6" (152mm) on side wall termina-

tions.

3 - If necessary, install a field-provided transition to adapt

larger vent pipe size to termination pipe size.

4 - On roof terminations, the intake piping should termi-

nate straight down using two 90° elbows (See figure

24).

5 - Exhaust piping must terminate straight out or up as

shown. In rooftop applications, a reducer may be re-

quired on the exhaust piping at the point where it exits

the structure to improve the velocity of exhaust away

from the intake piping. See table 8.

NOTE -Care must be taken to avoid recirculation of

exhaust back into intake pipe.

6 - On field supplied terminations for side wall exits, ex-

haust piping should extend a maximum of 12 inches

(305mm) beyond the outside wall unless supported.

Intake piping should be as short as possible. See fig-

ure 25.

7 - On field supplied terminations, the end of the exhaust

pipe must extend a minimum of 8" (203mm) beyond

the end of the intake pipe.

8 - If intake and exhaust piping must be run up a side wall

to position above snow accumulation or other obstruc-

tions, piping must be supported every 3 ft. (.9m) as

shown in figure 18. Refer to figure 28 for proper piping

method. In addition, the wall termination kit must be

extended for use in this application. See figure 31.

When exhaust and intake piping must be run up an

outside wall, the exhaust piping must be terminated

with pipe sized per table 8. The intake piping may be

equipped with a 90° elbow turndown. Using turndown

will add 5 feet (1.5m) to the equivalent length of the

pipe.

9 - Based on the recommendation of the manufacturer, a

multiple furnace installation may use a group of up to

four wall termination kits assembled together horizon-

tally, as shown in figure 30,

TABLE 8

EXHAUST PIPE TERMINATION SIZE REDUCTION

G71MPP

MODEL Exhaust Pipe Size Termination Pipe Size

070 2", 2-1/2", 3" or4" 1-1/2"

090 2", 2-1/2", 3" or4" 2"

110 2-1/2", 3" or4" 2"*

135 3" or 4" 2"*

*Approved 3" concentric termination kit terminates with 2-5/8" ID pipe.

8" (203)

MIN

3" (76) MAX. SIZE TERMINATION

--'_l _PIPE PER TABLE 8.

UNCONDITIONED

ATTIC SPACE

1/2" (13) FOAM

INSULATION IN

UNCONDITIONED

SPACE

2" (50) or

3" (80) PVC

Inches (mm)

PROVIDE SUPPORT

FOR INTAKE AND

EXHAUST LINES

DIRECT VENT ROOF TERMINATION KIT

(15F75 or 44J41)

FIGURE 24

12" (305) MAX.

1/2" (13)ARMAFLEX I(unless supported)

INSULATION IN _I=

UNCONDITIONED SPACE 1/2" (13)

_, ARMAFLEX

INSULATION

RE_)R;(_'_iEMDAy "_

BE REQUIRED

TO ADAPT I6" (152)

LARGERTERMINATIoNVENT_ _UM

PIPE SIZE TO

"=_ _ _ 2" (51) PVC

V L,No

ou s,o JI

WALL II MINIMUM I

Inches (rnm) TOP VIEW WALL RING KIT

(15F74)

FIGURE 25

Page 21

EXHAUST 12" (305) ABOVE

TERMINATION AVERAGE SNOW

ACCUMULATION

INTAKE

TERMINATION

Inches (ram)

FIELD-PROVIDED

REDUCER MAY BE REQUIRED

TO ADAPT LARGER VENT

PIPE SIZE TO TERMINATION

EXHAUST INTAKE

DIRECT VENT CONCENTRIC ROOFTOP TERMINATION

(71M80, 69M29 or 60L46)

FIGURE 26

Inches (ram) EXHAUST

FIELD-PROVIDED

REDUCER MAY I_

BE REQUIRED TO

ADAPT LARGER

VENT PiPE SIZE

TO TERMINATION

INTAKE

TERMINATION

EX.AUST

TERMINATION

12" (305) Min.

above grade.

DIRECT VENT CONCENTRIC WALL TERMINATION

(71 M80, 69M29 or 60L46)

FIGURE 27

Inches(ram)

UNCONDITIONED

SPACE

OUTSIDE WALL

12" (305) MAX. for 2" (51)

(unless supported) ,_11

SIZE

PROVIDE SUPPORT ---_TERMINATION

FOR INTAKE AND /PIPE PER

EXHAUST LINES EVERY / TABLE 8.

36" (914) /

FIELD-PROVIDED 12" (305) ABOVE

AVERAGE SNOW

REDUCER MAY ACCUMULATION

BE REQUIRED TO

ADAPT LARGER

VENT PIPE SIZE

TO TERMINATION

1/2" (13) FOAM

INSULATION IN

UNCONDITIONED 1/2" (13) FOAM

SPACE INSULATION

SIDE VIEW

DIRECT VENT WALL RING TERMINATION

(15F74)

See venting table 7for maximum venting lengths with this arrangement.

FIGURE 28

INTAKE ('_

VENT J)r'_... t

(with optional/I L__J

elbow) /

EXHAUST VENT

_ Front View

1/2" (13) Foam Insulation

in Unconditioned Space Side View

FIELD- L

PROVIDED EXHAUST VENT

REDUCER MAY

BE REQUIRED

TO ADAPT INTAKE

LARGER VENT VENT

PIPE SIZE TO |(with optional

TERMINATION elbow)

Inches (ram) OUTSIDE WALL

DIRECT VENT WALL TERMINATION KIT

(22G44, 44J40, 30G28 or 81J20)

FIGURE 29

(with optional

elbow /

_'_ _ _ _', "_'_'_ 12"

EXHAUST--_ [_)l L,__,_ /,\_)_ _-- '

VENT "" 5: .... /2" (i 05)

/ 1 127 III '

,NTAKE-- <i II¢-:tI III::

VENT I°_°ll _° I°_°ll °_ " "I

18" MAX.

(457) "_ Front View

Side View

Inches (mm) _>_._ EXHAUST VENT

_1_-'-,-,_ INTAKE

__ VENT

_ (with optional

elbow)

OPTIONAL VENT TERMINATION FOR MULTIPLE UNIT

INSTALLATION OF DIRECT VENT WALL TERMINATION KIT (30G28)

FIGURE 30

Page 22

INTAKE

AIR

GRADE

iiiililili_!!iii!ii!ii!ii!ii!ii!ii!ii!ii!ii!i_!i!!i_i_ii_iiii_;_;!

12" (305) MAX. for 2" (51)

20" (508) MAX. for 3" (76)

(unless supported) Inches (ram)

f- 71- -- -Iq

(C_ 1 _ _ EXHAUST

i _-_- --J ..... IJ AIR

__11_[_/_ 8" (203) I

!1 II _ _ 12"(305)

)1 Minimum

ABOVEGRAOE

Side View

INTAKE

AIR

(127

12" COVER EXHAUST

VENT WITH

1/2" (13)

FOAM

INSULATION

EXHAUST

AIR

12" MIN.

(305)

Above Grade

GRADE

Front View

DIRECT VENT TERMINATION

WALL TERMINATION KIT (22G44, 44J40, 30G28 or 81J20) EXTENDED VENT FOR GRADE CLEARANCE

FIGURE 31

G71MPP DIRECT VENT APPLICATION

USING EXISTING CHIMNEY STRAIOHT-CUTOR

ANGLE-CUT IN DIRECTION

OF ROOF SLOPE *

8 12

(203mm 30_,m)

INTAKE P_PE

INSULATION (opfl_al)

SHEET

METALTOP

PLATE

MINIMUM 12"

(305ram) ABOVE

ROOF

*SIZE TERMINATION

PIPE PER TABLE 8.

EXHAUSTVENT

1_" (13ram)

WEATHERPROOF

INSULAT_N

SHOULDER OF FITQNGS

PROVIDE SUPPORT

OF PIPE ON TOP PLATE

iALTERNATE

L--\:; ..,_._AKEP_PE

NOTE -Do not discharge exhaust gases directjy into any chimney or vent stack. If ver-

tical discharge through an existing unused chimney or stack is required, insert piping

inside chimney until the pipe open end is above top of chimney and terminate as illus-

trated. In any exterior portion of chimney, the exhaust vent must be insulated.

NOTE- If necessary the condensate trap may be installed

FIGURE 32

Condensate Piping

This unit is designed for either right- or left-side exit of con-

densate piping in either upfiow or downflow applications;

however, it must be installed on the same side of the unit as

the exhaust piping. In horizontal applications, the conden-

sate trap should extend below the unit. A 5-1/2" service

clearance is required for the condensate trap. Refer to fig-

ure 33 for condensate trap locations.

in an alternate location in upflow applications using kit

number 76M20.

CONDENSATE TRAP LOCATIONS

(Unit shown in upf!ow position)

Horizontal

left and

optional

downfiow

Optional

upflow

Horizontal

_] right and

J optional

downflow

Optional

upf!ow

NOTE -In upflow applications where side return

air filter is installed on same side as the conden-

sate trap, filter rack must be installed beyond

condensate trap to avoid interference.

FIGURE 33

Page 23

1- Determinewhichsidecondensatepipingwillexitthe

unit,Removeplugsfromthecondensatecollaratthe

appropriatelocationonthesideof theunit.

NOTE -The condensate trap is factory-shipped with

two rubber Q-rings and two rubber clean-out caps

installed. Check to make sure that these items are in

place before installing the trap assembly.

2- Install condensate trap onto the condensate collar.

Use provided HI/LO screws to secure two upper

flanges of the trap to the collar, Use provided sheet

metal screw to secure bottom trap flange to side of

unit, See figure 34,

NOTE - In upflow and downflow applications, con-

densate trap must be installed on the same side as

exhaust piping.

CAUTION

Condensate line must be sloped downward away from

condensate trap to drain, If drain level is above con-

densate trap, condensate pump must be used, Con-

densate drain line should be routed within the condi-

tioned space to avoid freezing of condensate and

blockage of drain line, If this is not possible, a heat

cable kit may be used on the condensate trap and line.

Heating cable kit is available from Lennox in various

lengths; 6 ft. (1.8m) - kit no. 26K68; 24 ft. (7.3m) - kit

no. 26K69; and 50 ft, (15.2m) - kit no, 26K70,

A CAUTION

5 - If unit will be started immediately upon completion of

installation, prime trap per procedure outlined in Unit

Start-Up section.

6- Glue the provided cap onto the unused condensate

drain line stub.

3- The grey-colored condensate trap (101661-01) pro-

vided with the unit is manufactured using ABS materi-

al. This is the only trap that is to be used with this unit,

Use ABS to PVC transition solvent cement to glue a

field-provided PVC coupling or PVC pipe to the trap.

Install a tee and vent pipe near the trap,

NOTE- The condensate trap drain stubs (both sides)

have an outer diameter which will accept a standard

3/4" PVC coupling. The inner diameter of each stub

will accept standard 1/2" diameter PVC pipe.

NOTE -Vinyl tubing may be used for condensate

drain. Tubing must be 1-1/4" QD X 1" ID and should be

attached to the drain stubs on the trap using a hose

clamp.

4 - Glue the field-provided drain line to the tee, Route the

drain line to an open drain. As an alternate, clear vinyl

tubing may be used to drain condensate away from

the trap. Secure the vinyl tubing to the drain stubs on

the trap using a hose clamp. Do not overtighten the

hose clamp.

O-RINGS

CONDENSATE ASSEMBLY

HI/LO SCREWS

(DO NOT use power

driver. Hand4ighten

using screw driver.)

/VENT

NIPPLE

CAP

SCREW

TEE

NIPPLE

COUPLING

_ CLEAN-OUT ACCESS

(both sides)

"_NDENSATE TRAP

(grey)

FIGURE 34

Page 24

-&CAUTION

AWARNING

1 - Gas piping may be routed into the unit through either

the left- or right-hand side. Supply piping enters into

the gas valve from the side of the valve as shown in

figures 36 and 37.

2 - When connecting gas supply, factors such as length of

run, number of fittings and furnace rating must be con-

sidered to avoid excessive pressure drop. Table 9 lists

recommended pipe sizes for typical applications.

NOTE -Use two wrenches when connecting gas pip-

ing to avoid transferring torque to the manifold.

3 - Gas piping must not run in or through air ducts, clothes

chutes, chimneys or gas vents, dumb waiters or eleva-

tor shafts. Center gas line through piping hole. Gas

line should not touch side of unit. See figures 36 and

37.

4 - Piping should be sloped 1/4 inch per 15 feet (6mm per

5.6m) upward toward the gas meter from the furnace.

The piping must be supported at proper intervals, ev-

ery 8 to 10 feet (2.44 to 3.05m), using suitable hangers

or straps. Install a drip leg in vertical pipe runs to serve

as a trap for sediment or condensate.

5 - A 1/8" N.P.T. plugged tap or pressure post is located

on the gas valve to facilitate test gauge connection.

See figures 44.

6 - In some localities, codes may require installation of a

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

staller) external to the unit. Union must be of the

ground joint type.

,IMPORTANT

MANUAL MAIN SHUT-OFF

VALVE WILL NOT HOLD

NORMAL TEST PRESSURE "_

CAP .------...._t-t

FURNACE

ISOLATE

GAS VALVE

FIGURE 35

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.

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.).

AIMPORTANT

AWARNING

Upflow Application AUTOMATIC

Left Side Piping GASVALVE

(Standard) (with manual

shut-off valve)

MANUAL

MAIN SHUT-OFF

VALVE

GROUND

JOINT

UNION

Upflow Application

Right Side Piping

(Alternate)

MANUAL

MAIN SHUT-OFF

VALVE

JOINT

UNION

DRIP LEG

FIELD

PROVIDED

AND INSTALLED

Figure 36

Page 25

Horizontal Applications

Possible Gas Piping Configerations

MANUAL

MAIN SHUT-OFF

VALVE

GROUND

JOINT

UNION

DRIP LEG

Horizontal Application

Right-Side Air Discharge

•-q

LUlII

_31 II

_'-J 2-"

MANUAL

MAIN SHUT-OFF _

VALVE

GROUND

JOINT

UNION

DRIP LEG

Horizontal Application

Left-Side Air Discharge

MANUAL

MAIN SHUT-OFF

VALVE

GROUND

JOINT

UNION

DRIP LEG

Nominal

Iron Pipe Size

-Inches(ram)

1/4

(6.35)

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)

(101.6)

FIGURE 37

TABLE 9

GAS PIPE CAPACITY -FTZ/HR (kL/HR)

Internal Length of Pipe-Feet(m)

Diameter 10 20 30 40 50 60 70

-Inches(ram) (3.048) (6.096) (9.144) (12.192) (15.240) (18.288) (21.336)

,364 43 29 24 20 18 16 15

(9.246) (1.13) (.82) (.68) (.57) (.51) (.45) (.42)

.493 95 65 52 45 40 36 33

(12.522) (2.69) (1.84) (1.47) (1.27) (1.13) (1.02) (.73)

.622 175 120 97 82 73 66 61

(17.799) (4.96) (3.40) (2.75) (2.32) (2.07) (1.87) (1.73)

.824 360 250 200 170 151 138 125

(20.930) (10.19) (7.08) (5.66) (4.81) (4.28) (3.91) (3.54)

1.049 680 465 375 320 285 260 240

(26.645) (19.25) (13.17) (10.62) (9.06) (8.07) (7.36) (6.80)

1,380 1400 950 770 660 580 530 490

(35.052) (39.64) (26.90) (21.80) (18.69) (16.42) (15.01) (13.87)

1.610 2100 460 1180 990 900 810 750

(40.894) (59.46) (41.34) (33.41) (28.03) (25.48) (22.94) (21.24)

2,067 3950 2750 2200 1900 1680 1520 1400

(52.502) (111.85) (77.87) (62.30) (53.80) (47.57) (43.04) (39.64)

2A69 6300 4350 3520 3000 2650 2400 2250

(67.713) (178.39) (123.17) (99.67) (84.95) (75.04) (67.96) (63.71)

3,068 11000 7700 6250 5300 4750 4300 3900

(77.927) (311.48) (218.03) (176.98) (150.07) (134.50) (121.76) (110.43)

4.026 23000 15800 12800 10900 9700 8800 8100

(102.260) (651.27) (447.39) (362.44) (308.64) (274.67) (249.18) (229.36)

(24.384)

(.40)

(.88)

(1.61)

118

(3.34)

220

(6.23)

460

(13.o3)

690

(19.54)

13oo

(36.81)

2050

(58.05)

3700

(lO4.77)

7500

(212.37)

NO TE - Capacity given in cubic feet of gas per hour (kilo liters of gas per hour) and based on O.60 specific gravity gas.

(27.432)

(.37)

(.82)

(1.50)

110

(3.11)

205

(5.80)

430

(12.18)

650

(18.41)

1220

(34.55)

1950

(55.22)

3450

(97.69)

7200

(203.88)

100

(30.480)

(.34)

(.76)

(1.42)

103

(2.92)

195

(5.52)

400

(11.33)

620

(17.56)

1150

(32.56)

1850

(52.38)

3250

(92.03)

6700

(189.72)

Page 26

ELECTROSTATIC DISCHARGE (ESD)

Precautions and Procedures

&CAUTION

INTERIOR MAKE-UP BOX INSTALLATION

MAKE-UP

BOX

Right Side

FIGURE 38

INTERIOR MAKE-UP BOX INSTALLATION

Left side

MAKE-UP

oBOX

FIGURE 39

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.

Refer to figure 40 and table 10 for field wiring and figure 41

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 40 and table 10. Use

18-gauge wire or larger that is suitable for Class II ra-

ting 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.

7 - One line voltage "EAC" 1/4" spade terminal is provided

on the furnace integrated control. Any electronic air

cleaner rated up to one amp can be connected to this

terminal with the neutral leg of the circuit being con-

nected to one of the provided neutral terminals. See

figure 42 for integrated control configuration. This ter-

minal is energized when the indoor blower is operating.

8- One line voltage *'HUM" 1/4" spade terminal is pro-

vided on the furnace integrated control. Any humidifier

rated up to one amp can be connected to this terminal

with the neutral leg of the circuit being connected to

one of the provided neutral terminals. See figure 42 for

integrated control configuration. This terminal is ener-

gized in the heating mode when the combustion air in-

ducer is operating.

9 - One 24V "H" terminal is provided on the furnace inte-

grated control terminal block. Any humidifier rated up

to 0.5 amp can be connected to this terminal with the

ground leg of the circuit being connected to either

ground or the "C" terminal. See figure 42 for integrated

control configuration.

Page 27

10-Installtheroomthermostataccordingto theinstruc-

tionsprovidedwiththethermostat,Seetable10for

thermostatconnections.If the furnace is being

matchedwitha heatpump,referto the instruction

packagedwiththedualfuelthermostat,

ThermostatSelection

TheG71MPPisdesignedtooperateinavariablerateca-

pacitymodeusingatwo-stagethermostat.TheG71MPP

willautomaticallyadjustfiringratebaseduponthermostat

cycletimes,Foroptimalperformance,Lennoxrecom-

mendsuseof a highqualityelectronicdigitalthermostat

withadjustablesettingsfor1ststage/2rid stage on /off dif-

ferentials and adjustable stage timers.

Lennox recommends the following two-stage thermostat

set-up for optimal variable rate capacity mode:

First heat stage differential set to 1/2 to 1 degree F; second

heat stage differential set to 1/2 or 1 degree F; second heat

stage upstage timer disabled, or set to maximum (1 hr mini-

mum).

Indoor Blower Speeds

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

blower will run continuously at a percentage of the sec-

ond-stage cooling speed when there is no cooling or

heating demand. The percentage is set using DIP

switches 6 and 7,

2 - When the G71MPP is running in the heating mode, the

integrated control will automatically adjust the blower

speed to match the furnace firing rate. This speed can

be adjusted up or down by 7,5% or 15% using DIP

switches 14 through 16 for the low heat speed and 17

through 19 for the high heat speed.

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

run on the cooling speed designated by the positions

of DIP switches 8 through 11,

TYPICAL G71MPP FIELD WIRING DIAGRAM

USE COPPER CONDUCTORS ONLY.

II IFIELD INSTALLED CLASS 024V

FIELD INSTALLED LINE VOLTAGE

FIELD SUPPLIED ACC WIRE

z_ DH AND L TERHINALS ARE NOT USED

_GEE WIRE HARNESS TASLE TO MATCH

HARNESS T8 FURNACE SIZE

120V ACC G

LI -_--ili

$102(2) COMBUSTION AIR

PREGGUREGAG GlIB

SWITCH LIMIT BACKUP GAS

SECONDARY VALVE

LIMIT cO

BURNERS HIGH HEAT

PRESSURE

@ SWITCH

-_ $1£8(G) _FLAME IGNITOR L_ _--_ $128(1)

LOW HEAT FLAME SENSOR 3159 FLAME /k_ LOW HEAT

PRESSURE ROLLOUT _P159 RDLLDUT PRESSURE

SWITCH SWITCH SWITCH SWITCH

s51E

A92

E)-3156 INTEGRATED

0 CONTROL 3246

-i I

ROOM THERMOSTAT

I@@@®©@@I _

j " ' t3c_

Ii L.......

I ....

OUTDOOR

UNIT C

_24_ INPUT

BF n [] P46

23456 183456

L-:___

I--4---

'I I I

L_ I I I

L_-_77 I

_),_)TO78 II I I

SENSOR II I 11 Ill II Z_ _

DDISCHAROE' 90DQ

TERHINAL BOARD t I

I i

r ..........

TRANSFORMER

CB8 'I--

CIRCUIT

BREAKER

SOl(If

SECONDARY

LIMIT

821(2)

SECONDARY

LIMIT

L1B @

POWER

CHOKE

INDOOR F _)

BLOWER

MOTOR

FIGURE 40

Page 28

Thermostat

1Heat /1 Cool

NOTE- Use DIP

switch 3 to set

second-stage

heat QN delay.

QFF-7 minutes.

0N-12 minutes.

1 Heat /2 Cool

NOTE- Use DiP

switch 3 to set

second-stage

heat ON delay.

QFF- 7 minutes,

0N-12 minutes.

1 Heat /2 Cool

with t'stat with

dehumidification

mode

NOTE- Use DIP

switch 3 to set

second-stage

heat ON delay.

QFF- 7 minutes,

0N-12 minutes.

DIP Switch 1

TABLE 10

Field Wiring Applications

DIP Switch Settings and On-Board Links (figure 42)

W914

W915

(Y1 to Y2) (DS to R)

Dehumidifi-

Two-Stage cation or

Cooling Harmony

III'"

ON Intact Intact

W951

(O to R)

Heat Pumps

Intact

Wiring Connections

S1 CONTROL OUTDOOR

T'STAT TERM. STRIP UNIT

® ® _)

® ®

® ® ®

® _,------Q

Cut

Intact

Cut

Intact

S1 CONTROL OUTDOOR

T'STAT TERM. STRIP UNIT

® ®

®®®

@ @- @

@. @ @

$1 CONTROL OUTDOOR

T'STAT TERM. STRIP UNIT

® ®

@ @---@

@ 4_---@

(_ @---@

*"R" required on some units.

Page 29

Thermostat

2 Heat /2 Cool

with t'stat with

dehumidifica-

tion mode

2 Heat/1 Cool

TABLE 10

Field Wiring Applications (Continued)

DIP Switch Settings and On-Board Links (figure 42)

DIP Switch 1

OFF

W915

(Y1 to Y2)

Two-Stage

Cooling

Cut

Intact

W914

(DSto R)

Dehumidifi-

cation or

Harmony

III"

Intact

Cut

Intact

W951

(O to R)

Heat Pumps

Intact

T'STAT

®.

Wiring Connections

CONTROL

TERM. STRIP

®-

CONTROL

TERM. STRIP

OUTDOOR

UNIT

* "R" required on some units.

OUTDOOR

UNIT

0----_

.@----@

_----_

$1 CONTROL OUTDOOR

T'STAT TERM. STRIP UNIT

¢- ®.

®____.__

,:2)- ® ®

O- @ @

Page 30

TABLE 10

Field Wiring Applications (Continued)

Thermostat

Dual Fuel

Single Stage

Heat Pump

ComfortSense

7000 L7724U

thermostat w/

dual fuel capa-

bilities

Capable of 2

stage gas heat

control

Dual Fuel

Two Stage

Heat Pump

ComfortSense

7000 L7724U

thermostat w/

dual fuel capa-

bilities

Capable of 2

stage gas heat

control

DIP Switch Settings and On-Board Link (figure 42)

W914

DIP Switch

DIP Switch 1

OFF

DIP Switch 1

OFF

W915

(Y1 to Y2)

Two-Stage

Cooling

Intact

Cut

(DS to R)

Dehumidifi-

cation or

Harmony

III ,r_

Intact

W951

(o to R)

Heat Pumps

Cut

Wiring Connections

CONTROL HEAT PUMP

L7724U TERM. STRIP

T'STAT

® ® ®

_)- -@ 67M41"

_. _.-o_

@ @ @

® ..... ..., @

® ® ®

®. ®

@ -_

® @

@ ® ®

® Flou,doo,

USellso,®

L7724U CONTROL TERM.

T'STAT STRIP HEAT PUMP

® ® ®

(_ _) 67M41"

@ @ ®

(:i:) _ @

@ @ ®

@ @

®. .®

® _). o.,b,.e

@ 4b ®

Q se"s°'U

*Connect W1 to W1 QNLYifusing defrost tempering kit 67M41

Page 31

TYPICAL G71MPP WIRING DIAGRAM

_7_ ........F --- _ (_7 P_4¸ i\J _ .....

li - ._ S12_(2) $47 B,-- F_A_E IGNIT3R IR331 $41 St28<I>

...... ............................................................................................................................iiii.........................................i siii il

SECONDARY

A92 LIMIT

INTEGRATED TI @

SI $51 CONTROL ,J_46 _ _RANSFDRNER

ROOM T_ERNQSTAT

BLOWER SPEE_ CHARI WIRING HARNESS fABLE

PART NO COLOR _TU_ RES_T

i0i551 Oi PURPLE 7O,O0O 24O

i36C-OS_ i_:: _A_ _70¸@¸¸¸¸¸5_

....... [iOiSGi-03 YELLOW IilO,ObO[lO% I

60c:1!_o 101551 _.LUE 135_000 1GO

NOTE, SEE INSTALLATION INSTRUCTIONS FOR z_ LI3 USED ON IaP ONLY

PROCEDURE TO SET CORRECT BLOWER SPEED FOR _ FACTORY DEFAUI T IS F_ A 2

SPECIFIC COOLING TONNAGE BEING APPLIED, STAG{ THEROOSTAT

AND HEARING tEMPERATURE RISE DESIRED _ FIELD SUPPLIED ACC WIRE

IYP!CAL SYSTEM SHOWN FOR 2 NEAT/2 COOL /_us£ COPPER CONDUCTORS ONLY

WITH A CONVENTIONAl THERMOSTAT, SEE ASI13 IS USED ON 090, ii0, AND

INSTAl{AT[ON INSTRUCTIONS FOR CONNECTIONS 135 UNITS ONLY

10 DINER EQUIPNEN] AN9 ACCESSORIES

_D[SCHARGE AN_ OUTDOOR AIR

A T_O STAGE THERMOSTAT RUST BE USED _ITH rERMINALS ARE FOR FUTURE USE

THIS FURNACE IN VARIABLE CAPACITY MODE _N_y

REFER rB INSFALLATION INSFRUCIIBNS _OR _24V PO_ER PROVIDED FOR

MORE INFgRMAF[ON ON RECaNMENDED TYPES OF

THERMOSTATS AND SETTINGS FOR OPTIMA{ OPTIONAL HUMI_IFIER DURING

HEAT DE_ANB

LINE VOLfAGE FELD INSTALLED

.... CLASS II VOLTAGE FZEID WIRING

_DENOTES OPTIONAL COMPONENTS

WARNING

ELECTRIC S_CK HAZARD,CAN CAUSE INJURY

_R DEAT_UNIr NUSF BE GROUNDED IN ACCORDANCE

WIT_ NATIONAL AN_ LOCAL CODES¸

NOIE-

IF ANY WIRE IN T_[S APPLIANCE ;S R_PLACED,IT

MUST BE REPLACED W!TH WIRE BF L_KE SIZE,

RAIING, INSULATION THICKNESS, AND TERMINATION¸

FIGURE 41

Page 32

INTEGRATED CONTROL

COMBUSTION

AIR INDUCER

CONNECTOR

DIAGNOSTIC

PUSH BUTTON_

DIP SWITCHES "_

OUTDOOR AIR_

SENSOR _..

TERMINALS

(Future Use)

DISCHARGE AIR _

SENSOR

TERMINALS

(Future Use)

FACTORY TEST

HEADER PINS.

FACTORY USE ONLY.

7-SEGMENT

DIAGNOSTIC LED

NEUTRAL

TERMINALS

IGNITOR

CONNECTOR

LINE VOLTAGE

TERMINALS

INDOOR

BLOWER

CONNECTOR

ON-BOARD

LINKS

1/4"QUICK CONNECT TERMINALS

HUM : 120 VAC OUTPUT TO HUMIDIFIER

XMFR = 120 VAC OUTPUT TO TRANSFORMER

LI = 120 VAC INPUT TO CONTROL

CIRC = 120 VAC OUTPUT TO CIRCULATING BLOWER

EAC = 120 VAC OUTPUT TO ELECTRONIC AIR CLEANER

NEUTRALS=120 VAC NEUTRAL

THERMOSTAT CONNECTIONS (TB1)

DS: DEHUMIDIFICATION SIGNAL

W2= HEAT DEMANDFROM 2ND STAGE T'STAT

Wl= HEAT DEMANDFROM IST STAGE T'STAT

R= CLASS 2 VOLTAGE TO THERMOSTAT

G= MANUAL FAN FROM T'STAT

C= THERMOSTATSIGNAL GROUNDCONNECTEDTO TRANSFORMER

GROUND (TR) &CHASIS GROUND (GRD)

YI: THERMOSTAT Ist STAGE COOL SIGNAL

Y2: THERMOSTAT 2rid STAGE COOL SIGNAL

O: THERMOSTAT SIGNAL TO HEAT PUMP REVERSING VALVE

H= 24V HUMIDIFIER OUTPUT

L= LENNOX SYSTEM OPERATION MONITOR

FIGURE 42

Page 33

TABLE 11

Thermostat Selection Switch Settings

Operation Thermostat Switch 1 Switch 2 Switch 3

Variable Capacity Heat Two-Stage Off On Off

(40% to 100%)

Three-Stage Heat Single-Stage On Off 2nd stage delay

(40%, 70%, 100%) OFF = 7 minutes

ON = 12 minutes

3rd stage delay

10 minutes fixed

Two-Stage Heat (W1 70%, W2 100%) Two-Stage Off Off Off

G71MPP units are equipped with a variable-capacity, van-

able-speed integrated control. This control manages igni-

tion timing, combustion air inducer speed, heating mode

fan off delays and indoor blower speeds based on selec-

tions made using the control DIP switches and on-board

links. The control includes an internal watchguard feature

which automatically resets the ignition control when it has

been locked out,

Heating Operation DIP Switch Settings -- Figure 42

Switch 1 -- Thermostat Selection -- This unit may be

used with either a single-stage or two-stage thermostat.

The thermostat selection is made using a DIP switch which

must be properly positioned for the particular application.

The DIP switch is factory-positioned for use with a two-

stage thermostat, If a single-stage thermostat is to be used,

the DIP switch must be repositioned, See table 11,

Switch 2 -- Operating Mode with Two-Stage Thermo-

stat -- If a two-stage thermostat is used, the furnace can

operate in either variable-capacity or conventional two-

stage mode, When variable-capacity mode is selected, the

firing rate of the unit is varied to maximize comfort, Conven-

tional two-stage mode is the factory default setting, See

table 11,

Switch 3 -- Second-Stage Heat On Delay -- If a single-

stage thermostat is used, the integrated control can be

used to energize second-stage heat after either 7 minutes

or 12 minutes of first-stage heat operation, See table 11.

Switches 4 and 5 -- Blower-Off Delay -- The blower-on

delay of 45 seconds is not adjustable. The blower-off delay

(time that the blower operates after the heating demand

has been satisfied) can be adjusted by moving switches 4

and 5 on the integrated control, The unit is shipped from the

factory with a blower-off delay of 90 seconds, The blower

off delay affects comfort and is adjustable to satisfy individ-

ual applications. Adjust the blower off delay to achieve a

supply air temperature between 90° and 110°F at the exact

moment that the blower is de-energized, Longer off delay

settings provide lower supply air temperatures; shorter set-

tings provide higher supply air temperatures, Table 12 pro-

vides the blower off timings that will result from different

switch settings,

TABLE 12

Blower Off Delay Switch Settings

Blower Off Delay Switch 4 Switch 5

(Seconds)

60 Off On

90 Off Off

120 On Off

180 On On

Indoor Blower Operation DIP Switch Settings

Switches 6 and 7 -- Continuous Indoor Fan Operation-

Blower Speed -- Switches 6 and 7 are used to select blow-

er motor speeds during continuous indoor blower opera-

tion, The unit is shipped from the factory with the DIP

switches positioned for medium low (2) speed during con-

tinuous indoor blower operation, The table below provides

the continuous blower speeds that will result from different

switch settings, Refer to tables 21 through 31 for corre-

sponding cfm values,

TABLE 13

Continuous Indoor Blower Operation -- Blower Speeds

Speed Switch 6 Switch 7

1 - Low Off On

2 - Medium Low Off Off

(Factory)

3-Medium High On Off

4 - High On On

Page 34

Switches8 and 9 -- Cooling Mode Blower Speed --

Switches 8 and 9 are used to select cooling blower motor

speed The unit is shipped from the factory with the DIP

switches positioned for high speed (4) indoor blower motor

operation during the cooling mode The table below pro-

vides the cooling mode blower speeds that will result from

different switch settings Refer to tables 21 through 31 for

corresponding cfm values

TABLE 14

Cooling Mode Blower Speeds

Speed Switch 8 Switch 9

1 - Low On On

2 - Medium Low Off On

3 - Medium High On Off

4- High (Factory) Off Off

Switches 10 and 11 -- Cooling Mode Blower Speed Ad-

justment -- Switches 10 and 11 are used to select blower

speed adjustment settings The unit is shipped from the

factory with the DIP switches positioned for NORMAL (no)

adjustment The DIP switches may be positioned to adjust

the blower speed by +10% or -10% to better suit the ap-

plication Table 15 provides blower speed adjustments that

will result from different switch settings Refer to tables 21

through 31 for corresponding cfm values

With switches 10 and 11 set to ON, motor will bypass ramp-

ing profiles and all delays and will immediately run at se-

lected COOLING speed upon a call for cool LED will con-

tinue to operate as normal This mode is used to check

motor operation TABLE 15

Cooling Mode Blower Speed Adjustment

Adjustment Switch 10 Switch 11

+10% (approx) On Off

NORMAL (Factory) Off Off

-10% (approx) Off On

MOTOR TEST On On

Switches 12 and 13 -- Cooling Mode Blower Speed

Ramping -- Switches 12 and 13 are used to select cooling

mode blower speed ramping options Blower speed ramp-

ing may be used to enhance dehumidification perfor-

mance The switches are factory set at option A which has

the greatest effect on blower motor performance Table 16

provides the cooling mode blower speed ramping options

that will result from different switch settings The cooling

mode blower speed ramping options are detailed below

NOTE -The off portion of the selected ramp profile only ap-

plies during heat pump operation in dual fuel applications

TABLE 16

Cooling Mode Blower Speed Ramping

Ramping Option Switch 12 Switch 13

A (Factory) Off Off

B On Off

C Off On

D On On

Ramping Option A (Factory Selection)

• Motor runs at 50% for 30 seconds

• Motor then runs at 82% for approximately 7-1/2 minu-

tes

• If demand has not been satisfied after 7-1/2 minutes,

motor runs at 100% until demand is satisfied

• Once demand is met, motor runs at 50% for 30 sec-

onds then ramps down to stop

__ 7 1/2 MIN .__ 100% --D,._

OFF 82% CFM CFM OFF

1/2 MIN

50% CFM

i_ COOLING DEMAND

Ramping Option B

• Motor runs at 82% for approximately 7-1/2 minutes If

demand has not been satisfied after 7-1/2 minutes,

motor runs at 100% until demand is satisfied

• Once demand is met, motor ramps down to stop

(

,_p 7 1/2 MIN _ 100% CFM

OFF 82%CFM /

COOLING DEMAND --"IP"

OFF

Ramping Option C

• Motor runs at 100% until demand is satisfied

• Once demand is met, motor runs at 100% for 45 sec-

onds then ramps down to stop

_._p-- lOO% CFM --

OFF OFF

-- DEMAND

Ramping Option D

• Motor runs at 100% until demand is satisfied

• Once demand is met, motor ramps down to stop

100% CFM _OFF

COOLING

DEMAND

Page 35

Switches 14 through 19 -- Heating Mode Blower Speed

-- Switches 14 through 19 are used to select heating mode

blower motor speeds. These switches are factory set at the

OFF position which provides 100 % of normal speed during

HIGH HEAT demand, 70% of normal speed during MID-

RANGE HEAT demand and 40% of normal speed during

LOW HEAT demand. Switches 14, 15 and 16 are used to

adjust the LOW HEAT blower motor speed, Switches 17,

18 and 19 are used to adjust the HIGH HEAT blower motor

speed, Table 17 provides the heating mode blower speeds

that will result from different switch settings. Refer to tables

21 through 31 for corresponding cfm values,

TABLE 17

Low Heat Blower Speeds

Thermostat

Demand

Low Heat

(Rto Wl)

Blower

Speed

Adjust-

ments

+15%

+7.5%

Normal

-7.5%

-15%

DIP SWITCH SETTINGS

14 15 16

On Off On

On Off Off

Off Off Off

On On Off

On On On

Thermostat

Demand

High Heat

(R to

w1 & w2)

TABLE 18

High Heat Blower Speeds

Blower DIP SWITCH

Speed

Adjust-

ments

+15%

+7.5%

Normal

-7.5%

-15%

SETTINGS

17 18 19

On Off On

On Off Off

Off Off Off

On On Off

On On On

On-Board Link W914 -- Figure 42

On-board link W914, is a clippable connection between ter-

minals DS and R on the integrated control. W914 must be

cut when the furnace is installed with either the Harmony

111'" zone control or a thermostat which features humidity

control. If the link is left intact the PMW signal from the Har-

mony Iti control will be blocked and also lead to control

damage. Refer to table 19 for operation sequence in ap-

plications including G71MPP, a thermostat which features

humidity control and a single-speed outdoor unit. Table 20

gives the operation sequence in applications with a two-

speed outdoor unit,

On-Board Link W951 -- Figure 42

On-board link W951 is a clippable connection between ter-

minals R and O on the integrated control. W951 must be cut

when the furnace is installed in applications which include a

heat pump unit and a thermostat which features dual fuel

use, If the link is left intact, terminal "O" will remain ener-

gized eliminating the HEAT MODE in the heat pump,

On-Board Link W915 -- Figure 42

On-board link W915 is a clippable connection between ter-

minals Y1 and Y2 on the integrated control. W915 must be

cut if two-stage cooling will be used. If the link is not cut the

outdoor unit will operate in second-stage cooling only,

Diagnostic LED -- Figure 42

The seven-segment diagnostic LED displays operating

status, target airflow, error codes and other information,

The table on page 58 lists diagnostic LED codes,

Diagnostic Push Button -- Figure 42

The diagnostic push button is located adjacent to the

seven-segment diagnostic LED. This button is used to en-

able the Error Code Recall mode and the Field Test mode.

Press the button and hold it to cycle through a menu of op-

tions, Every five seconds a new menu item will be dis-

played. When the button is released, the displayed item will

be selected. Once all items in the menu have been dis-

played, the menu resumes from the beginning until the but-

ton is released,

Error Code Recall Mode

Select "E" from the menu to access the most recent 10 error

codes. Select "c" from the Error Code Recall menu to clear

all error codes, Button must be pressed a second time

while "c" is flashing to confirm command to delete codes.

Press the button until a solid "---"is displayed to exit the Error

Code Recall mode,

Field Test Mode

Use the diagnostic push button to scroll through the menu

as described above. Release the button when the LED

flashes "-" to select the Field Test mode.

While in the Field Test mode the technician can:

• Initiate furnace ignition and move to and hold low-fire

rate by applying a R to W1 jumper.

• Initiate furnace ignition sequence and move to and

hold high-fire rate by applying a jumper from R to W1

and W2.

• Initiate furnace ignition sequence and move to and

hold mid-fire rate by applying a jumper to R and W2.

• Apply then remove the jumper from R to W1 and W2 to

change the firing rate from low fire to mid fire and high

fire.

• A vent calibration sequence can be initiated even if a

thermostat signal is not present. Press and hold the

push button until a solid "C" is displayed. Release the

button and calibration will begin. The furnace will per-

form the high-fire and low-fire pressure switch calibra-

tions and display "CAL". After calibration, the LED will

return to the flashing "-" display.

During Field Test mode operation, all safety switches are

still in the circuit (they are not by-passed) and indoor blower

performance and timings will match DIP switch selections.

Current furnace firing rate, indoor blower CFM and flame

signal will be displayed. To exit the Field Test mode, press

and hold the button. The menu will resume from the begin-

ning. Also, cycle the main power to exit the Field Test

mode. The integrated control will automatically exit the

Field Test mode after 45 minutes of operation.

Page 36

G71MPP INTEGRATED CONTROL CONFIGURATION GUIDE

2NO STAGEHEAT ON DELAY

BIAGE 3 UPSTAGE

SINGLE BEIAY ! MIN FIXED

SAGE ONIY

(TIME STA ING>

(S_ _ BN ONLY)

407 7_% I087

1 23 4

]NIN

UPSTAGE

DELAY

ia3¢

_2 MN

UPSTAGE

DEAY

CONTINUOUSFAN MODEBLOWERSPEED

las4

MEDIUMoLOVsPEED(38X)

LOW

SPEED

(28X)

MEDIUM HIGH I 2 s 4 _ m

SPEED

(70X>

HIGH

(IOOX.)

FELB TEST MOE CONTSERRORCODERECALL(SEECOL LIST FOR3 DIGITC_ES)

• HOLD BUTTONUNTIL SOLID ' ' IS DISPLAYEDTEN RELEAS! VENT CALIBRATION

CYCLESTHROUGHLASTi0 ERRORCODES(EXXXqIX_<) LOV FIRE JUMPERR TOVI JHOL_UNTIL SOL[_ "C" [S DISPLAYED

• TOCLEAR VH[LE IN ERRORRECALL_ HOLDBUTTON HIGH FIRE JUMPERR TO WI & V2 THENRELEASE

UNTILSOLED'E' IS _[SPLAYE_II{N RELEASE¸PRESSBUTTON MID FIRE JUMPERR TO V2 ONLY CAL VENT CALIBRATIONIN

DURINGBLINKING'c" TOCONFIRM_EETE ERRORCOL& (HT Z) AXXX(CFN) FXXX (_A) TO

• TO EXIT RECALL HOLDBUTTONUNI_L ' E' [S DISPLAYED FLAME SIGNAL

2-STAGE EAT MODE

(SV #1 O_ ONLY>

CONVENTIONAL

2STG HEATING _[AGNOSTICLED QUICKREFERENCE

MODE [_LE' _LINKING 'O'

WARMUP:BLINKING"H"

VI 70_, VR OOX hXX (INPUT%) P_

VARIABLE GAPAC Y _ II _ (STG) #_U£EAXXXX

HEATING MODE s 4 _ 6 •_ FAN=AXXX(CFM)

(WB]]ULATION)

PREFERRED MODE VENT CALIBRATION:CAL (CFN)

4OX TO 10% BASEDUPQ SEE MANUALFOR COMPLETELEST

DMAND

HEALING _LOWEN-OFF DELAY

90 SECOND i 2 s

HID BLOWER

OFF DEIAY

60 SECOND

MIG DIOVER

OFF DFLAY

w i 4

NORMAL/MODIFIED LOW HEAT SPEED

HEAT SPEED

GY2 YI C

MODIFIEDLOW

HEAl SPEED

SEESV15,16

INCREASE/DECREASE IOV HEAT SPEED

INCREASE LOW

HEAT SPEED

([OVER OAT)

SE SV

]]ECREASF LOW

HEAl SPEED

( NCREAS ] !}AT)

SEE SW 16 i4

CHANGE lOW HEAT SPEED

_CHANGE IoOV

HEAT SPEED BY

7Z 14

CHANGEIOV

HEATSPEEDBY

15X

I-STG COMPRESSOR AIC UNIT

2 STAGE

COMPR

O0 NOT CUT

2-STO COMPRESSOR HEAT PUMP UNIT

R STAGE

CUT LINK

2°STAGE HEAT PUMP LINK

COMPRESSOR LINK (JUMPERS R to 0)

(JUNFERS Y1 to YO) v951

WS_B

SEE IN EGRATED CONTROL _EIAILE9 SETUP IN BRMATON PRO £CI!VE PLASIIC[LM Q_,DIP S_ITCHES MAY BE

£8R COMPLETE S_TUP & CONFIGURATIONPETAILS REMOVER FOR EASE IN SETTING BF DIP SV

COOLING MODE BLOWER SPEED

HIGH

SPEED

NFDIUMIIIGN

SPFED

MEDIUNLOV

SPEED

LOW

SPEED

SPEED ADJUSIMENI

NORMA

+ 107,

fox

COOLINGMODE BLOWER RAMPING

OPTION A

OFF-SO%-8R%-

!0OX-5OX-OFF

NORMAL /MODIFIED HIGH HEAl SPEED

HEAT CFM

MODEIED NIGH

ND HARMONYZONING

HARMONY ZONING

SIGNATURESTAT V/

DS CONNECTION

CUT LINK

DEHUN

HARMONY

DENUMIDIIICAFION

HARMONY lINK

(JUMPERS Rto DR)

W914

INCREASE/DECREASE HIGH HEAT SPEE_

INCREASE HIGH

NEAT SPEED

(LOVER DAD

SEE sw 19

DECREASE H1Gil

HEAT SPEED

(!NCREASE DAD

SEE SV 19

CHANGE HIGH HEAT SPEED

CHANGE HIGH _

MEAT STPy.EEDBY

CHANG] NGN

IEAT SPEED BY

CUI ON I_AR INK (SBL_R IRACE)COMPLEE y IRU611

BgT lAYERS QN THE CONTRO BARD

LINKS CUT IN ERRUR INSIALL A JUMPER ON IHE AP_ROPRIAYE

IER_ NALS#N THE TERMI_,ALS{RIP

FIGURE 43

Page 37

TABLE 19

OPERATING SEQUENCE

G71MPP, ComfortSense" 7000 Thermostat and Single-Stage Outdoor Unit

OPERATING T

• s¥s EM DEMAND

SEQUENCE .

System Thermostat Demand

Condition Step I°1

NO CALL FOR DEHUMIDIFICATION

Normal Operation 1 On On On

Relative Humidity Blower

Compressor CFM

Status I D (COOL)

Acceptable VAC High 100%

Comments

Compressor and indoor

blower follow thermostat

demand

BASIC MODE (only active on a Y1 thermostat demand)

Normal Operation 1 On On On

Dehumidification

Call 2 On On On

Acceptable VAC High

Demand VAC High

1oo%

7o%

ComfortSense T`'7000

thermostat energizes Y1

and de-energizes D on a

call for de-humidification

PRECISION MODE (operates ind_ oendent of a Y1 thermostat demand)

Normal Operation 1 On On On

Dehumidification 2 On On On

call

Dehumidification 1 On On On Demand

call ONLY

Acceptable VAC High

Demand VAC High

VAC High

100%

70%

On-board links at indoor unit with a single-stage outdoor unit:

With Condensing unit - Cut W914 (R to DS) on SureLight ® integrated control;

With Heat Pump - Cut W914 (R to DS) & W951 (R to O) on SureLight ® integrated

control,

Dehumidification mode

begins when humidity is

greater than set point

ComfortSense T`'7000

thermostat will keep out-

door unit energized after

cooling temperature set-

point has been reached in

order to maintain room

humidity setpoint.

Page 38

TABLE 20

OPERATING SEQUENCE

G71MPP, ComfortSense '" 7000 Thermostat and Two-Stage Outdoor Unit

OPERATING T "-

SEQUENCE SXS EM DEMAND . SYS'EM RESPONSE

Thermostat Demand Relative Humidity Blower

s s,e ste0ii iii Co 0 esso

Condition Y1 Y2 O G W W

1 2 Status D (COOL)

NO CALL FOR DEHUMIDIFICATION

Normal Operation - 24

Y1 1 On On On Acceptable VAC Low

Normal Operation - 24

Y2 2 On On On On Acceptable VAC High

ROOM THERMOSTAT CALLS FOR FIRST STAGE COOLING

BASIC MODE (only active on a Y1 thermostat demand)

Normal Operation 1 On On On Acceptable VAC Low

Dehumidification 0

Call 2 On On On On Demand VAC High

PRECISION MODE (operates independent of a Y1 thermostat demand)

Normal Operation 1 On On On Acceptable VAC Low

Dehumidification 0

call 2 On On On On Demand VAC High

Dehumidification 0

call ONLY 1 On On On On Demand VAC High

ROOM THERMOSTAT CALLS FOR FIRST AND SECOND STAGE COOLING

BASIC MODE (only active on a Y1 thermostat demand)

Normal Operation 1 On On On On Acceptable VAC

Dehumidification 0

2 On On On On Demand

Call VAC

PRECISION MODE (operates independent of a Y1 thermostat demand)

Normal Operation

Dehumidification

call

Dehumidification

call ONLY

On On On Acceptable VAC

On On On On Demand VAC

Comments

70% Compressor and indoor

blower follow thermostat

100% demand

70% ComfortSense T_7000

thermostat energizes Y2

and de-energizes D on a

70% call for de-humidification

70% Dehumidification mode

begins when humidity is

70% greater than set point

70%

ComfortSense T'_7000

thermostat will keep out-

door unit energized after

cooling temperature set-

_oint has been reached

in order to maintain room

humidity setpoint.*

High

100% ComfortSense T_7000

thermostat energizes Y2

and de-energizes D on a

70% call for de-humidification

Low 70%

High 70%

1 On On On On Demand VAC High 70%

On-board links at indoor unit with a two-stage outdoor unit:

Cut factory link from Y1 to Y2 or cut W915 (Y1 to Y2) on SureLight ® integrated

control,

With Condensing unit - Cut W914 (R to DS) on SureLight ® integrated control;

With Heat Pump - Cut W914 (R to DS) & W951 (R to O) on SureLight ®

integrated control,

Dehumidification mode

begins when humidity is

greater than set point

ComfortSense T" 7000

thermostat will keep out-

door unit energized after

cooling temperature set-

3oint has been reached

in order to maintain room

humidity setpoint.

Page 39

TABLE 21

G71MPP-36B-070 BLOWER PERFORMANCE (less filter)

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM iiiiiiiiiiiiiiiiiiiiiiiiiiiiii ! ! !ii! i! i! i! i! i! i! i! i! i! i! i! i! i! i! i! i! !i

Heating Input Ran

50% 60%

610 690

575 645

545 610

52o 58o

490 54o

e and Blower Volume - CFM

80%

87O

810

76O

715

655

9O%

975

9O5

845

79O

715

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High IMedium- IMedium IHigh

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 730 815 865 935 1015 1190 1280 1395

Default Cool CFM 880 755 795 855 930 1065 1155 1270

Decrease (-10%) Cool CFM 625 695 730 775 830 950 1010 1105

The effect of static pressure is included in air volumes shown.

Lennox Harmony Ill _ Zone Control Applications - Minimum blower speed is 250 cfm.

The following control configurations are available. See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns).

With two-stage thermostat there are two modes available.

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only).

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 250 cfm,

G71MPP-36B-070 BLOWER MOTOR WATTS - COOLING

I Motor Watts @ Various External Static Pressures-in. wg.

Blower Speed First Stage /

10.1010.2010.3010.4010.5010.6010.7010.800 [0.1010.2010.30ondS/ao.5010.6010.7010.8osec tge

Options 0 [ 0.40

Increase (+10%) Cool CFM

Low 55 70 90 110 130 145 160 175 190 135 155 175 200 220 245 270 295 320

Medium-Low 75 90 110 130 150 170 190 205 220 185 215 250 285 315 345 370 395 420

Medium-High 85 100 120 145 165 185 205 225 250 235 265 300 335 370 400 425 455 480

High 105 125 150 170 190 210 235 255 280 315 340 370 395 440 480 510 540 570

Default Cool CFM

Low 45 60 80 95 115 130 145 160 175 100 120 140 165 190 215 235 255 275

Medium-Low 60 75 95 110 130 145 165 180 200 140 165 190 220 245 265 290 315 340

Medium-High 65 85 105 125 140 155 175 195 215 175 200 230 260 285 310 340 365 390

High 85 100 120 140 160 180 200 220 240 230 260 295 325 360 390 410 435 455

Decrease (-10%) Cool CFM

Low 40 55 70 85 100 120 130 145 160 75 90 110 125 150 175 190 210 225

Medium-Low 45 60 80 95 115 135 145 160 175 95 120 150 175 200 220 240 260 285

Medium-High 50 65 85 105 125 145 160 175 190 125 150 175 195 220 240 265 290 320

High 60 75 95 115 135 150 170 190 215 165 190 215 245 265 485 315 340 370

Page 40

TABLE 22

G71MPP-36C-090 BLOWER PERFORMANCE (less filter)

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii i! !i!!i!!i!!i!!i!!i!!i!!i!!i!!i!!i!!i!!i!!i!!i!!i!i;

Heating Input Range and Blower Volume - CFM

50% 60% 80% 90%

740 825 1005 1100

695 775 94o 1025

655 725

615 680

575 630

870 950

815 890

745 805

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High Medium- Medium High

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 705 790 845 920 1020 1185 1275 1395

Default Cool CFM 650 730 770 830 905 1060 1145 1270

Decrease (-10%) Cool CFM 600 670 705 750 800 925 1010 1100

Theeffect of static pressure is included in air volumes shown,

Lennox Harmony Ill " Zone Control Applications - Minimum blower speed is 250 cfm.

Thefollowing control configurations are available, See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns),

With two-stage thermostat there are two modes available.

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only).

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 250 cfm.

G71MPP-36C-090 BLOWER MOTOR WATTS -COOLING

Motor Watts @ Various External Static Pressures - in. wg.

Blower Speed First Stage Second Stage

Options010.1010.2010.3010.4010.5010.6010.7010.80010.1010.2010.3010.4010.5010.6010.7010.80

Increase (+10%) Cool CFM

Low 35 50 70 90 105 125 140 160 175 85 110 135 160 185 205 235 265 295

Medium-Low 45 60 80 100 125 150 170 185 205 125 155 185 220 245 275 305 330 360

Medium-High 60 75 95 110 135 160 180 200 220 165 195 230 265 300 330 355 380 410

High 65 85 110 135 160 180 205 225 245 210 245 285 325 360 390 425 460 495

Default Cool CFM

Low 35 45 60 75 95 115 130 145 160 60 80 110 135 155 175 195 215 235

Medium-Low 40 55 70 90 110 130 150 165 185 105 125 145 170 200 225 250 270 295

Medium-High 45 60 80 95 115 135 155 175 195 115 140 175 205 235 265 290 315 335

High 50 65 85 105 130 155 180 200 220 155 185 220 255 285 315 345 380 415

Decrease (-10%) Cool CFM

Low 30 40 55 75 90 105 120 135 150 55 65 85 105 125 150 170 190 210

Medium-Low 40 50 65 80 100 120 130 145 160 65 90 120 145 165 185 205 225 250

Medium-High 40 55 70 90 105 125 140 160 180 85 105 135 165 185 210 235 260 285

High 45 60 75 90 115 135 155 170 190 105 125 150 175 210 240 275 305 335

Page 41

TABLE 23

G71MPP-60C-090 BLOWER PERFORMANCE (less filter)

Bottom Return Air, Return Air from Both Sides or Return Air from Bottom and One Side

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM

iiiiiiiiiiiiiii_i_;!i;ii:ii:i_:i_!_i!_!i!i_i_i_i_i_i_i_i_i_i_!_!_i_i_f_ii_

iiiiiiiiiiiiiiiiiiiii i i!iii ii!i!! ! !ii i i i i i i i i ii i ! ii!i !ii!ii! iii iiii i

Heating Input Ran

50% 60%

800 935

730 860

715 820

630 740

565 665

eand Blower Volume - CFM

80%

1205

1110

1035

96O

87O

90%

1335

1235

1150

1070

97O

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High I Medium- I Medium I High

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 1105 1185 1355 1545 1605 1710 1925 2165

Default Cool CFM 995 1080 1205 1345 1440 1560 1755 1960

Decrease (-10%) Cool CFM 890 960 1090 1215 1275 1380 1590 1755

The effect of static pressure is included in air volumes shown.

Lennox Harmony Ill " Zone Control Applications - Minimum blower speed is 450 cfm,

The following control configurations are available. See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns),

With two-stage thermostat there are two modes available,

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only).

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 450 cfm.

G71MPP-60C-090 BLOWER MOTOR WATTS -COOLING

Bottom Return Air, Return Air from Both Sides or Return Air from Bottom and One Side

I Motor Watts @ Various External Static Pressures-in. wg.

Blower Speed First Stage /

10.1010.2010.3010.4010.5010.6010.7010.80 0 10.1010.2010.3oOndSa0.5010.6010.7010.80Sectge

Options 010.40

Increase (+10%) Cool CFM

Low 115 135 160 185 205 230 255 275 300 305 340 375 410 440 475 505 535 565

Medium-Low 145 165 190 215 240 265 285 305 325 355 390 430 470 510 550 580 610 635

Medium-High 170 200 240 275 305 335 370 400 430 510 555 600 645 690 730 765 795 830

High 265295330365400435465500535725780835895935975 100 1031065

Default Cool CFM

Low 90 110 130 155 175 195 215 235 255 220 250 285 320 350 385 415 450 485

Medium-Low 110 130 155 180 200 220 245 265 285 270 305 345 385 420 455 485 515 545

Medium-High 145 165 190 215 245 270 295 320 340 390 425 465 500 540 580 610 640 670

High 180 205 240 270 300 330 365 395 430 540 580 625 670 710 755 795 830 870

Decrease (-10%) Cool CFM

Low 70 85 105 125 145 165 185 205 225 160 190 220 255 275 300 330 360 390

Medium-Low 80 100 120 140 165 190 210 225 245 195 225 260 295 325 350 385 415 450

Medium-High 110 130 160 185 205 225 250 275 300 295 330 365 400 430 460 495 535 570

High 155 175 195 220 245 270 295 315 340 400 435 470 510 545 585 610 640 665

Page 42

TABLE 24

G71MPP-60C-090 BLOWER PERFORMANCE (less filter) -- Single Side Return Air

(Air volumes in bold require field fabricated transition to accommodate 20 x 25 x 1 in. cleanable air filter

in order to maintain proper air velocity across the filter.)

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM

iiiiiiii'ii'ii i!iiiiili! !! !! !i!i¸!I¸!I¸!I¸!I !i !i !i !i !i !i !i ii i i! i! i! i!ii!iiiiiiiiiii!iiii

Heating Input Range and Blower Volume - CFM

50% 60% 80% 90%

790 920 iiiiiiiiiiiiiiiiiiiil;!;i;!;;!_iii_!i_!!!!;!i!!i!!i!!i!i!i!i!i!i!i!i!i1180 1310

725 850 1090 1205

675 790 iiiiii?!!i! iii,i i !!i!i!!!iiiii!i!ii!iiiilililililililil1015 1125

625 730 iiiiiiiiiiiiiiiiiiiii__i_!i!__i__i_i_ii_i!i!__!!i!!i!!i!iii__i__i__i__i__i__i__i__i__i__i__i__i_i!i_i940 1045

565 665 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii_______!!!!_!!_!!_!!_!!_!!_!!_!!_!!_!!_!!_!!_!!_!!_!!_!!_!__!i_860 960

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High Medium- Medium High

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 1080 1160 1315 1490 1575 1690 1895 2135

Default Cool CFM 985 1060 1185 1330 1405 1530 1735 1935

Decrease (-10%) Cool CFM 865 930 1065 1185 1250 1355 1560 1735

The effect of static pressure is included in air volumes shown,

Lennox Harmony Ill " Zone Control Applications - Minimum blower speed is 450 cfm.

The following control configurations are available, See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns),

With two-stage thermostat there are two modes available.

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only).

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 450 cfm.

G71MPP-60C-090 BLOWER MOTOR WATTS - COOLING

Motor Watts @ Various External Static Pressures - in. wg.

Blower Speed First Stage

Options 0 10.1010.2010.3010.4010.5010.6010.7010.800 {0.1010.2010.SoC°ndSlag_o{0.6010.7010.8010.40

Increase (+10%) Cool CFM

Low

Medium-Low

Medium-High

High

Default Cool CFM

Low

Medium-Low

Medium-High

High

Decrease (-10%) Cool CFM

Low

Medium-Low

Medium-High

High

565

645

84O

105

46O

53O

67O

865

445

510

635

765

Page 43

TABLE 25

G71MPP-60C-090 BLOWER PERFORMANCE (less filter) -- Side Return Air with Optional RAB Return Air Base

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM

Heating Input Ran

50% 60%

770 895

710 825

660 775

605 710

555 650

eand Blower Volume - CFM

80%

1155

1070

1005

92O

845

90%

1290

1195

1115

1030

945

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High IMedium- IMedium IHigh

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 1060 1135 1285 1455 1525 1655 1860 2100

Default Cool CFM 960 1035 1165 1310 1385 1500 1695 1905

Decrease (-10%) Cool CFM 865 920 1050 1165 1240 1320 1510 1695

The effect of static pressure is included in air volumes shown,

Lennox Harmony Ill _ Zone Control Applications - Minimum blower speed is 450 cfm,

The following control configurations are available. See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns),

With two-stage thermostat there are two modes available,

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only).

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 450 cfm.

G71MPP-60C-090 BLOWER MOTOR WATTS -COOLING

Side Return Air with Optional RAB Return Air Base

IMotor Watts @ Various External Static Pressures-in. wg.

Blower Speed First Stage /

10.1010.2010.3010.4010.5010.6010.7010.80 0 10.1010.2010.3oOndSa0.5010.6010.7010.80Sectge

Options 0 I 0.40

Increase (+10%) Cool CFM

Low 110 130 150 175 195 215 240 265 290 275 305 340 380 410 440 470 505 540

Medium-Low 130 155 175 200 220 245 265 290 315 360 390 420 455 485 515 550 590 625

Medium-High 160 190 220 255 280 305 335 360 390 490 530 570 610 645 680 715 750 785

High 220 255 295 330 365 400 430 460 490 695 750 805 855 895 935 965 995 1025

Default Cool CFM

Low 80 95 120 140 165 190 210 235 255 190 225 265 305 330 355 390 420 455

Medium-Low 100 120 140 165 190 215 235 255 275 265 295 325 355 390 420 455 495 530

Medium-High 140 160 185 205 235 260 285 305 325 375 410 440 475 500 530 570 610 650

High 180 205 240 270 300 325 350 380 405 520 560 605 645 685 720 760 805 845

Decrease (-10%) Cool CFM

Low 70 85 105 125 140 160 180 200 220 155 175 200 225 255 290 315 340 365

Medium-Low 80 95 115 135 155 175 200 220 245 185 210 235 260 295 325 355 385 415

Medium-High 105 125 150 175 200 220 240 265 290 255 290 330 365 400 430 460 490 520

High 135 160 185 215 235 260 285 305 330 370 400 440 475 505 530 565 600 635

Page 44

TABLE 26

G71 MPP-60C-110 BLOWER PERFORMAN CE (less filter)

Bottom Return Air, Return Air from Both Sides or Return Air from Bottom and One Side

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM

Heating Input Range and Blower Volume - CFM

50%

1050

975

96O

86O

79O

60%

1215

1125

1075

99O

910

80%

1535

1430

1335

1250

1145

90%

1695

1585

1480

1380

1260

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High Medium- Medium High

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 945 1020 1160 1300 1625 1745 1990 2210

Default Cool CFM 840 910 1055 1180 1465 1580 1790 1995

Decrease (-10%) Cool CFM 740 800 920 1045 1290 1405 1605 1790

The effect of static pressure is included in air volumes shown,

Lennox Harmony Ill _ Zone Control Applications - Minimum blower speed is 450 cfm,

The following control configurations are available, See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns),

With two-stage thermostat there are two modes available.

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only),

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DiP switch selectable) of the same second-stage COOL speed position

minimum 450 cfm

G71MPP-60C-110 BLOWER MOTOR WATTS -COOLING

Bottom Return Air, Return Air from Both Sides or Return Air from Bottom and One Side

Motor Watts @ Various External Static Pressures - in. wg.

Blower Speed First Stage

10.1010.2010.3010.4010.5010.6010.7010.80 0 10.1010.2010.3oOndS/a0.5010.6010.7010.80sectge

Options 0 10.40

Increase (+10%) Cool CFM

Low 75 90 115 135 160 180 200 220 240 280 315 350 390 430 475 510 550 585

Medium-Low 90 105 130 150 175 200 220 245 270 340 380 425 465 505 545 575 610 645

Medium-High 120 140 170 195 225 250 275 300 330 510 545 585 620 675 735 770 805 840

High 160 185 210 235 265 290 325 360 395 710 755 805 855 905 950 980 101 1035

Default Cool CFM

Low 55 70 90 110 135 155 175 195 215 205 235 275 310 345 380 415 450 485

Medium-Low 75 90 105 125 150 170 190 215 235 250 285 325 360 400 440 470 505 540

Medium-High 95 115 135 160 190 220 240 265 285 375 410 445 485 530 575 605 635 670

High 125 150 175 200 225 255 280 305 335 510 550 595 640 685 725 770 815 860

Decrease (-10%) Cool CFM

Low 45 60 80 100 115 125 145 160 180 155 180 210 240 270 295 325 355 385

Medium-Low 55 70 85 105 125 150 165 185 200 185 215 245 280 315 345 380 415 450

Medium-High 70 85 105 125 150 170 195 215 235 265 300 345 385 425 465 500 535 570

High 95 110 135 160 190 220 240 260 280 375 415 455 495 535 575 615 650 690

Page 45

TABLE 27

G71MPP-60C-110 BLOWER PERFORMANCE (less filter) -- Single Side Return Air

(Air volumes in bold require field fabricated transition to accommodate 20 x 25 x 1 in. cleanable air filter

in order to maintain proper air velocity across the filter.)

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM

i!ijjjj !!i!i!i iiiii!i i!!i!!i!ii !ii iiiii i!i ililililililililiiiiiiiiiiill

iiiiiiii'ii i! i!iiiiiii! !! !! !i¸!i!i!i i i i i i !!i!!i!!i!!i!!i!!i!!i!!i!!i!!ii!i!ii!!ii!iiiiliiiii iill

iiiiiiiiiiiiiiiiiii i i! i! ! ii! ! i i !i!i!i!i!i!i!i!i!i!i!iiiiiii!i i!

i!i!i!i!i!i!i!i!i!i!i!i!i!i!iiii

Heating Input Ran

50% 60%

1030 1185 iiiiiiiiiiiiiiiiiiiiii;_i!_i_i_!i_!i_!i_!i_!i_!i_!_!_!_!_!_!_!_!_!_iI

955 lO95

840 965 iiiiiiiiiiiiiiiiiiiiiiiii_:iii_19_5_!i_!i_!i_!i_!i_!i_!i_!i_!i_!i_!i_!_!i!!!_!_

765 880 ......................................................

e and Blower Volume - CFM

80%

1490

1380

1305

1210

1110

90%

1630

1525

1435

1330

1225

iiiiiiiii'ii i!iiiiiiiili! !! !! !i!i¸!I¸!tiiii ii ! iiii!ii!ii!ii!ii!ii!ii!iii ii iiiiiiiiiiiiiiiiiiiii!!

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High IMedium- IMedium IHigh

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 935 1025 1155 1285 1585 1700 1905 2135

Default Cool CFM 840 915 1050 1175 1435 1535 1740 1930

Decrease (-10%) Cool CFM 750 800 925 1050 1280 1385 1570 1755

The effect of static pressure is included in air volumes shown,

Lennox Harmony Ill" Zone Control Applications - Minimum blower speed is 450 cfm,

The following control configurations are available. See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns).

With two-stage thermostat there are two modes available.

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only).

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 450 cfm.

G71 MPP-60C-110 BLOWER MOTOR WATTS - COOLING

IMotor Watts @ Various External Static Pressures - in. wg.

Blower Speed First Stage Second Stage

o tions0I0.10I0.20I0.30I0. 0I0.50I0.80I0.70I0.800I0.10I0.20I0.30I0. 0I0.50I0.80I0.70I0.80

Increase (+10%) Cool CFM

Low 70 90 110 130 150 165 185 210 230 255 295 345 390 430 470 510 545 585

Medium-Low 85 105 125 150 170 190 215 235 255 340 375 415 455 490 525 570 615 660

Medium-High 115 135 160 185 210 230 255 285 310 455 500 555 610 655 695 750 800 850

High 155 175 195 220 250 285 310 335 360 650 710 770 835 880 920 960 995 1035

Default Cool CFM

Low 60 75 90 110 125 145 165 185 205 195 230 270 305 345 380 415 455 490

Medium-Low 70 85 105 125 140 160 180 200 220 225 265 315 360 400 440 475 515 555

Medium-High 95 110 130 150 175 200 225 245 265 365 400 445 485 525 565 610 650 690

High 115 135 165 190 215 235 260 285 310 495 535 580 625 675 725 770 815 860

Decrease (-10%) Cool CFM

Low

Medium-Low

Medium-High

High

4OO

455

57O

69O

Page 46

TABLE 28

G71MPP-60C-110 BLOWER PERFORMANCE (less filter) -- Side Return Air with Optional RAB Return Air Base

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM

Heating Input Range and Blower Volume - CFM

50%

1020

950

895

835

765

60%

1175

1095

1030

96O

88O

80%

1485

1385

1300

1210

1110

90%

1635

1535

1435

1335

1220

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High Medium- Medium High

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 1085 1155 1310 1475 1555 1685 1895 2130

Default Cool CFM 955 1050 1185 1335 1415 1540 1735 1930

Decrease (-10%) Cool CFM 850 920 1070 1195 1245 1350 1545 1725

Theeffect of static pressure is included in air volumes shown,

Lennox Harmony Ill _' Zone Control Applications - Minimum blower speed is 450 cfm.

The following control configurations are available. See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns).

With two-stage thermostat there are two modes available.

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only).

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 450 cfm.

G71MPP-60C-110 BLOWER MOTOR WATTS -COOLING -Side Return Air with Optional RAB Return Air Base

Motor Watts @ Various External Static Pressures - in. wg.

Blower Speed First Stage Second Stage

Options0 10.1010.2010.3010.4010.5010.8010.7010.800 10101020103010401050108010701080

Increase (+10%) Cool CFM

Low 105 125 150 175 200 220 245 265 290 250 285 320 360 395 435 470 500 535

Medium-Low 130 150 175 200 220 240 270 295 320 335 365 405 445 480 515 550 590 630

Medium-High 165 190 220 250 275 305 335 370 400 470 505 545 585 630 670 710 755 800

High 205 240 285 330 360 390 420 450 485 655 695 745 790 840 885 925 965 1005

Default Cool CFM

Low 75 90 115 135 160 185 205 225 250 190 220 255 290 325 360 395 430 460

Medium-Low 100 120 145 165 185 205 230 255 280 250 285 325 360 390 420 455 485 520

Medium-High 135 155 175 200 230 260 280 305 330 355 395 435 475 510 545 580 620 660

High 170 195 225 255 290 320 350 375 405 475 515 565 610 655 705 745 785 825

Decrease (-10%) Cool CFM

Low 55 70 90 110 135 155 175 195 220 150 170 200 225 255 285 315 340 370

Medium-Low 65 80 105 130 150 170 195 215 240 165 195 230 265 300 330 360 390 420

Medium-High 100 125 150 180 200 220 240 260 280 240 280 320 360 400 435 470 505 540

High 140 160 180 200 230 260 285 305 330 350 385 420 455 500 540 575 610 645

Page 47

TABLE 29

G71MPP-60D-135 BLOWER PERFORMANCE (less filter)

Bottom Return Air, Return Air from Both Sides or Return Air from Bottom and One Side

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM

Heating Input Ran

50% 60%

1220 1390

1130 1290

1045 1195

975 1110

890 1020

eand Blower Volume - CFM

80%

1725

1600

1495

1390

1275

90%

1885

1750

1650

1535

1405

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High I Medium- I Medium I High

Low Low High (Default) Low Low High (Default)

i i i

Increase (+10%) Cool CFM 1135 1205 1365 1540 1615 1730 1945 2190

Default Cool CFM 1025 1105 1235 1390 1455 1580 1780 1985

Decrease (-10%) Cool CFM 915 985 1115 1235 1305 1400 1600 1780

The effect of static pressure is included in air volumes shown.

Lennox Harmony Ill _ Zone Control Applications - Minimum blower speed is 450 cfm.

The following control configurations are available. See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns),

With two-stage thermostat there are two modes available,

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only).

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 450 cfm.

G71 MPP-60D-135 BLOWER MOTOR WATTS - COOLING

Bottom Return Air, Return Air from Both Sides or Return Air from Bottom and One Side

I Motor Watts @ Various External Static Pressures-in. wg.

Blower Speed First Stage /

Options010.1010.2010.3010.4010.5010.6010.7010.80

Increase (+10%) Cool CFM

Low

Medium-Low

Medium-High

High

Default Cool CFM

Low

Medium-Low

Medium-High

High

Decrease (-10%) Cool CFM

Low

Medium-Low

Medium-High

High

Second Stage

010.1010.2010.3010.4010.5010.6010.7010.80

515

6O5

75O

98O

43O

5OO

625

775

355

415

515

610

Page 48

TABLE 30

G71MPP-60D-135 BLOWER PERFORMANCE (less filter) -- Single Side Return Air

(Air volumes in bold require field fabricated transition to accommodate 20 x 25 x 1 in. cleanable air filter

in order to maintain proper air velocity across the filter.)

0 through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM

Heating Input Range and Blower Volume - CFM

50%

1160

1075

1005

93O

85O

60%

1325

1225

1145

1060

970

80%

1640

1520

1425

1325

1215

90%

1790

1670

1570

1470

1345

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High Medium- Medium High

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 1105 1180 1330 1500 1585 1705 1905 2130

Default Cool CFM 990 1075 1210 1355 1430 1545 1765 1975

Decrease (-10%) Cool CFM 890 950 1085 1210 1275 1370 1565 1755

The effect of static pressure is included in air volumes shown,

Lennox Harmony Ill " Zone Control Applications - Minimum blower speed is 450 cfm.

The following control configurations are available, See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns),

With two-stage thermostat there are two modes available.

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only).

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 450 cfm.

G71MPP-60D-135 BLOWER MOTOR WATTS -COOLING

Motor Watts @ Various External Static Pressures - in. wg.

Blower Speed First Stage

10.1010.2010.3010.4010.5010.6010.7010.80 0 10.1010.2010.3oOndS/a0.5010.6010.7010.80Sectge

Options 0 I 0.40

Increase (+10%) Cool CFM

Low 90 110 140 170 195 220 240 265 290 230 265 310 355 390 425 460 490 525

Medium-Low 105 130 165 195 215 235 260 290 315 285 330 380 430 455 485 525 565 605

Medium-High 150 175 205 235 270 300 330 360 385 425 465 515 560 605 645 685 730 770

High 195 230 270 305 340 375 410 445 480 605 650 695 740 800 855 900 945 985

Default Cool CFM

Low

Medium-Low

Medium-High

High

Decrease (-10%) Cool CFM

Low

Medium-Low

Medium-High

High

455

5O5

645

810

36O

42O

510

635

Page 49

TABLE 31

G71MPP-60D-135 BLOWER PERFORMANCE (less filter) -- Side Return Air with Optional RAB Return Air Base

0through 0.80 in. w.g. External Static Pressure Range

HEATING BLOWER PERFORMANCE

Heating Adjust CFM Selections

Increase (+15%) Heat CFM

Increase (+7.5%) Heat CFM

Default Heat CFM

Decrease (-7.5%) Heat CFM

Decrease (-15%) Heat CFM

Heating Input Ran

50% 60%

1180 1340

1095 1245

1020 1160

945 1075

870 990

e and Blower Volume - CFM

8O%

1650

1535

1435

1335

1230

90%

1800

1680

1575

1475

1350

COOLING BLOWER PERFORMANCE

Blower Speed Selections

Cooling Adjust CFM First Stage Cool Speed - cfm Second Stage Cool Speed - cfm

Selections Medium- Medium High I Medium- I Medium I High

Low Low High (Default) Low Low High (Default)

Increase (+10%) Cool CFM 1080 1155 1310 1480 1550 1660 1875 2105

Default Cool CFM 985 1055 1190 1325 1400 1510 1720 1920

Decrease (-10%) Cool CFM 875 945 1060 1190 1250 1345 1530 1715

The effect of static pressure is included in air volumes shown,

iii i ; iii i!!!!!!!!!i!i!ii!ii!iliiii itil

Lennox Harmony Ill _' Zone Control Applications - Minimum blower speed is 450 cfm,

The following control configurations are available, See Installation Instructions for details and DIP switch settings.

Heat Mode (Heating Blower Performance Table):

With a single-stage thermostat, furnace will operate at three, staged rates (40/70/100%) with a time delay between each stage (values in grey-shaded

columns),

With two-stage thermostat there are two modes available,

Traditional two-stage mode - W1 demand results in 70% firing rate. W2 results in 100% firing rate. No delay between stages. (values shown in 70%

and 100% grey-shaded columns only),

Variable Rate Capacity Mode - furnace automatically adjusts firing rate based on first- and second-stage cycle times. (all columns)

Cool Mode (Cooling Blower Perfomance table):

First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.

Continuous Fan speeds are approximately 28%, 38%, 70% and 100% (DIP switch selectable) of the same second-stage COOL speed position

minimum 450 cfm.

G71MPP-60D-135 BLOWER MOTOR WATTS -COOLING - Side Return Air with Optional RAB Return Air Base

I Motor Watts @Various External Static Pressures-in. wg.

Blower Speed First Stage /

10.1010.2010.3010.4010.5010.6010.7010.800 10.1010.2010.30ondS/ao.5010.6010.7010.8osec tge

Options 010.40

Increase (+10%) Cool CFM

Low 90 110 140 165 190 210 235 260 285 235 265 305 340 380 415 450 480 515

Medium-Low 105 130 160 190 210 230 255 285 310 290 325 370 410 450 490 515 545 575

Medium-High 145 170 205 235 265 290 325 355 390 420 460 510 555 595 640 680 715 755

High 200 230 270 305 345 385 415 445 480 580 630 690 745 800 850 895 935 975

Default Cool CFM

Low 70 90 115 140 165 190 210 230 250 170 200 235 270 305 335 370 400 430

Medium-Low 90 105 125 150 175 200 225 250 270 200 230 270 310 355 400 435 465 495

Medium-High 115 140 170 195 225 250 275 300 325 330 365 400 440 485 525 555 585 615

High 145 175 205 240 270 295 330 365 395 435 480 530 580 625 675 715 750 790

Decrease (-10%) Cool CFM

Low 60 75 95 115 135 155 175 195 215 135 155 180 205 240 280 305 330 355

Medium-Low 70 90 110 130 150 170 195 215 235 160 185 215 240 275 310 345 375 410

Medium-High 85 105 130 155 180 205 230 250 270 220 255 295 335 370 410 440 475 510

High 120 140 170 195 220 240 270 295 325 330 365 400 440 480 525 555 585 615

Page 50

FORYOURSAFETYREADBEFOREOPERATING

,&,WARNING

,AWARNING

BEFORE BEFORE PLACING THE UNIT INTO OPERA-

TION, smell all around the furnace 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 G71MPP is equipped with a gas con-

trol switch. Use only your hand to move the control switch,

Never use tools. If the switch will not move by hand, do not

try to repair it, Call a licensed professional service techni-

cian (or equivalent), Force or attempted repair may result in

a fire or explosion,

Placing the furnace into operation:

G71MPP units are equipped with an automatic ignition sys-

tem. Do not attempt to manually light burners on this fur-

nace. 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 this ignition system,

-&WARNING

A,CAUTION

-&WARNING

Priming Condensate Trap

The condensate trap should be primed with water prior to

start-up to ensure proper condensate drainage. Either pour

10 fl, oz. (300 ml) of water into the trap, or follow these steps

to prime the trap:

1 - Follow the lighting instructions to place the unit into op-

eration,

2 - Set the thermostat to initiate a heating demand,

3 - Allow the burners to fire for approximately 3 minutes,

4- Adjust the thermostat to deactivate the heating de-

mand,

5 - Wait for the combustion air inducer to stop, Set the

thermostat to initiate a heating demand and again al-

low the burners to fire for approximately 3 minutes.

6- Adjust the thermostat to deactivate the heating de-

mand and again wait for the combustion air inducer to

stop. At this point, the trap should be primed with suffi-

cient water to ensure proper condensate drain opera-

tion,

Gas Valve Operation (Figure 44)

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 - Move the gas valve switch to the OFF position, See fig-

ure 44,

7 - Wait five minutes to clear out any gas. tf 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.

8 - Move gas valve switch to the ON position, See figure

44, Do not force,

INLET

SUPPLY _

PRESSURE TAP

GAS VALVE

NEGATIVE AIR POSITIVE AIR MANIFOLD

PRESSURE PORT PRESSURE PORT PRESSURE TAP

OUTLET

GAS VALVE SHOWN IN OFF POSITION

FIGURE 44

Page 51

9- Replacetheupperaccesspanel,

10- Turnonallelectricalpowertototheunit,

11- Setthethermostatto desiredsetting,

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-Move the gas valve switch to the OFF position.

5 - Replace the upper access panel,

Gas Flow (Approximate)

TABLE 32

Gas Flow Rate (Ft._/Hr.)

Seconds for 1

Revolution

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 - Operate unit at least 15 minutes before checking gas

flow. Determine the time in seconds for one revolu-

tions of gas through the meter,

2-Compare the number of seconds and the gas meter

size in table 32 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.

Manifold Pressure Measurement

To correctly measure manifold pressure, the differential

pressure between the positive gas manifold and the nega-

tive burner box must be considered, Use pressure test

adapter kit (available as Lennox part 10L34) to assist in

measurement.

1 - Connect test gauge "+" connection to manifold pres-

sure tap on gas valve,

2 - Tee into the gas valve regulator vent hose and con-

nect test gauge "-" connection,

3 - Start unit on low heat (40% rate) and allow 5 minutes

for unit to reach steady state,

4 - While waiting for the unit to stabilize, notice the flame.

Flame should be stable and should not lift from burner,

Natural gas should burn blue,

5- After allowing unit to stabilize for 5 minutes, record

manifold pressure and compare to value given in table

33.

6 - Repeat steps 3, 4 and 5 on high heat,

NOTE- Shut unit off and remove manometer as soon as an

accurate reading has been obtained. Take care to replace

oressure tap plug.

A,CAUTION

Page 52

NOTE -In Canada, certification for installations at eleva-

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

thorities.

G71MPP units require no manifold pressure adjustments

for operation at altitudes up to 10,000 feet (3048m) above

sea level. Units installed at altitude of 7,501 to 10,000 feet

(2287 to 3048m) require a pressure switch change per

table 33. Table 33 lists conversion kit requirements pres-

sure switch requirements and manifold pressures at all alti-

tudes.

NOTE- The values given in table are measurements only.

The gas valve should not be adjusted.

The combustion air pressure switch is factory-set and re-

quires no adjustment,

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

necessary to convert this unit. Refer to the changeover kit

installation instruction for the conversion procedure.

TABLE 33

Conversion Kit Requirements and Manifold Test Pressures

Model

Input

Size

-O7O

-090

-110

-135

LP/Propane High Altitude Pressure Manifold Pressure at All Altitudes (in. w.g.)

Kit Switch Kit

0 - 10,000

(0 - 3048 m)

33W41

0 - 7,500 7,501 - 10,000

(0 - 2286 m) (2287 -

3048rn)

36W77

40W05

Not required 40W06

40W07

Low Fire

(40% rate)

Natural Gas LP/Propane

0.7 2.0

High Fire

(100% rate)

Natural Gas LP/Propane

3.5 10.0

NOTE -Pressure switch is factory set. No adjustment necessary. All models use the factory installed pressure switch from 0-7,500 feet (0- 2286m).

NOTE -See previous page for manifold pressure measurement procedure.

Page 53

Primary and Secondary Limits

The primary limit is located on the heating compartment

vestibule panel, The secondary limits are located in the

blower compartment, attached to the back side of the blow-

er, These limits are factory set and require no adjustment,

Flame Rollout Switches (Two)

These manually reset switches are located on the burner

box, If tripped, check for adequate combustion air before

resetting,

Pressure Switches (Three)

The pressure switches are located in the heating compart-

ment on the combustion air inducer, These switches check

for proper combustion air inducer operation before allow-

ing ignition trial, The switches are factory-set and require

no adjustment,

Back-Up Secondary Limit (090, 110 and 135)

The back-up secondary limit is located on the combustion

air inducer. This switch protects the plastic components

from overheating due to indoor blower motor failure, If

tripped, check for proper blower operation before resetting,

Temperature Rise

After the furnace has been started and supply and return

air temperatures have been allowed to stabilize, check the

temperature rise with the unit operating at 100 percent fir-

ing rate. 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 adjust the temperature rise

may cause erratic limit operation.

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,

Electronic Ignition

The 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. This type of lockout is usually due to low gas line

pressure, 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,

Exhaust and Air Intake Pipe

1 - Check exhaust and air intake connections for tightness

and to make sure there is no blockage,

2- Are pressure switches closed? Obstructed exhaust

pipe will cause unit to shut off at pressure switches,

Check termination for blockages,

3- Reset manual flame rollout switches on burner box

cover.

Failure To Operate

If the unit fails to operate, check the following:

1 - Is the thermostat calling for heat?

2 - Are access panels securely in place?

3 - Is the main disconnect switch closed?

4 - Is there a blown fuse?

5 - Is the filter dirty or plugged? Dirty or plugged filters will

cause the limit control to shut the unit off.

6 - Is gas turned on at the meter?

7 - Is the manual main shut-off valve open?

8 - Is the internal manual shut-off valve open?

9 - Is the unit ignition system in lock out? If the unit locks

out again, call the service technician to inspect the unit

for blockages.

10 - Is blower harness connected to ignition control? Fur-

nace will not operate unless harness is connected.

Page 54

Theintegratedcontrolinitiatesapressureswitchcalibra-

tionattheinitialunitstart-uponacallforheat.Theignition

controlwillalsoinitiateacalibrationanytimemainpoweris

turnedoffandbackonandaheatingdemandis present.

Additionalcalibrationsmaybeinitiatedbytheservicetech-

nicianduringfieldtestsequence.Thefollowingheatingse-

quenceof operationassumescompletionofasuccessful

calibration.

NOTE -The thermostat selection DIP switch on the inte-

grated control is factory-set in the "TWO-S TAGE" position.

Applications Using a Two-Stage Thermostat

A - Heating Sequence -- Control Thermostat Selection

DIP switch in "Two-Stage" Position (Factory Setting)

1 - On a call for heat, thermostat first-stage contacts close

sending a signal to the integrated control. The inte-

grated control runs a self-diagnostic program and

checks high temperature limit switches for normally

closed contacts and pressure switches for normally

open contacts.The combustion air inducer is ener-

gized at ignition speed, which is approximately the

same as the inducer speed at 70 percent firing rate.

2- Once the control receives a signal that the low-fire

pressure switch has closed, the combustion air induc-

er begins a 15-second pre-purge in the ignition speed.

3 - After the pre-purge is complete, a 20-second initial ig-

nitor warm-up period begins. The combustion air in-

ducer continues to operate at the ignition speed.

4 - After the 20-second warm-up period has ended, the

gas valve is energized and ignition occurs. At the

same time, the control module sends a signal to begin

an indoor blower 45-second ON-delay. When the

delay ends, the indoor blower motor is energized at a

speed that matches the firing rate. After the 10-second

ignition stabilization delay expires, the inducer speed

is adjusted to the appropriate target rate. The inducer

will remain at the 70 percent speed as long as the ther-

mostat has a first-stage heating demand.

5 - If second-stage heat is required, the thermostat sec-

ond-stage heat contacts close and send a signal to the

integrated control. The integrated control initiates a

30-second second-stage recognition delay.

6 - At the end of the recognition delay and on all subse-

quent calls for heat in the same heating cycle, the inte-

grated control energizes the combustion air inducer at

high speed. The control also checks the high-fire pres-

sure switch to make sure it is closed. As the inducer

speed is increased to high, the indoor blower motor is

adjusted to a speed which is appropriate for the target

rate.

7-When the demand for high-fire (second stage) heat is

satisfied, the gas valve is de-energized and the field-

selected indoor blower off delay begins. The combus-

tion air inducer begins a 20-second post-purge period.

8 - When the combustion air post-purge period is com-

plete, the inducer is de-energized. The indoor blower

is de-energized at the end of the off delay.

Applications Using a Two-Stage Thermostat

B - Heating Sequence -- Control Thermostat Selection

DIP switch in "Variable Capacity" Position

1 - On a call for heat, thermostat first-stage contacts close

sending a signal to the integrated control. The inte-

grated control runs a self-diagnostic program and

checks high temperature limit switches for normally

closed contacts and pressure switches for normally

open contacts.The combustion air inducer is ener-

gized at ignition speed, which is approximately the

same as the inducer speed at 70 percent firing rate.

2 - Once the control receives a signal that the low-fire

pressure switch has closed, the combustion air induc-

er begins a 15-second pre-purge in low speed.

3 - After the pre-purge is complete, a 20-second initial ig-

nitor warm-up period begins. The combustion air in-

ducer continues to operate at the ignition speed.

4 - After the 20-second warm-up period has ended, the

gas valve is energized and ignition occurs. At the

same time, the control module begins an indoor blow-

er 45-second ON-delay. When the delay ends, the in-

door blower motor is energized at a speed that

matches the firing rate. After the 10-second ignition

stabilization delay expires, the inducer speed is ad-

justed to the appropriate target rate. If the furnace is

operating in the initial heating cycle after power-up,

the initial firing rate will be approximately 40 percent.

The firing rate on subsequent cycles will be automati-

cally adjusted by the integrated control based on ther-

mostat cycles. The firing rate will vary and will range

from 40 percent to 90 percent. The furnace will contin-

ue this operation as long as the thermostat has a first-

stage heating demand.

5 - If second-stage heat is required, the thermostat sec-

ond-stage heat contacts close and send a signal to the

integrated control. The integrated control either in-

creases the firing rate to 70 percent (if the current rate

is at or below 60 percent) or increases the firing rate

by 10 percent (if the current rate is above 60 percent).

If the call for heat continues 5 minutes beyond this ini-

tial upstage, the rate will be increased by 10 percent

every 5 minutes until the call for heat is satisfied or the

furnace reaches 100 percent rate. As the firing rate in-

creases, the indoor blower motor is adjusted to a

speed which is appropriate for the target rate.

6- If second-stage heat demand is satisfied, but first

stage is still present, the furnace will continue to oper-

ate at the present firing rate until the heat cycle ends.

7 - When the demand for first- and second-stage heat is

satisfied, the gas valve is de-energized and the field-

selected indoor blower off delay begins. The combus-

tion air inducer begins a 20-second post-purge period.

Page 55

8- Whenthecombustionair post-purgeperiodis com-

plete,theinducerisde-energized.Theindoorblower

isde-energizedattheendoftheoffdelay.

ApplicationsUsingA Single-StageThermostat

C- HeatingSequence-- ControlThermostatSelection

DIPswitchin "Single-Stage"Position

1- Onacallforheat,thermostatfirst-stagecontactsclose

sendinga signalto theintegratedcontrol.Theinte-

gratedcontrolrunsa self-diagnosticprogramand

checkshightemperaturelimitswitchesfor normally

closedcontactsandpressureswitchesfor normally

opencontacts.Thecombustionair induceris ener-

gizedattheignitionspeed,whichisapproximatelythe

sameastheinducerspeedat70percentfiringrate.

2- Oncethecontrolreceivesa signalthatthelow-fire

pressureswitchhasclosed,thecombustionairinduc-

erbeginsa15-secondpre-purgeattheignitionspeed.

3- Afterthepre-purgeiscomplete,a20-secondinitialig-

nitorwarm-upperiodbegins,Thecombustionairin-

ducercontinuestooperateattheignitionspeed,

4 - Afterthe20-secondwarm-upperiodhasended,the

gasvalveisenergizedandignitionoccurs,whichiniti-

atesa 10-secondignitionstabilizationdelay.At the

sametime,thecontrolmodulesendsasignaltobegin

an indoorblower45-secondON-delay.Whenthe

delayends,theindoorblowermotorisenergizedata

speedwhichisappropriateforthefiringrate.Afterthe

10-secondignitionstabilizationdelayexpires,thein-

ducerspeedisadjustedto40percentspeed.Theinte-

gratedcontrolalsoinitiatesasecond-stageondelay

(factory-setat7 minutes;adjustableto 12minutes).

5- Iftheheatingdemandcontinuesbeyondthesecond-

stageondelay,theintegratedcontrolenergizesthe

combustionairinducerat 70percentspeed.Thein-

door blowermotoris adjustedto a speedwhich

matchesthetargetrate.Afixed,10-minutethird-stage

ondelayisinitiated.

6- If theheatingdemandcontrinuesbeyondthethird-

stageondelay,theintegratedcontrolenergizesthein-

ducerat highspeed.Theindoorblowermotorisad-

justedto a speedwhichis appropriateforthetarget

rate.

7 -Whenthethermostatheatingdemandissatisfied,the

gasvalveisde-energizedandthecombustionairin-

ducerbeginsa 20-secondpost-purge.Thefield-se-

lectedindoorbloweroffdelaybegins.

8- Whenthecombustionairpost-purgeperiodis com-

plete,theinducerisde-energized.Theindoorblower

isde-energizedattheendoftheoffdelay.

Page56

AWARNING

At the beginning of each heating season, system should be

checked as follows by a qualified service technician:

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,

AWARNING

Filters

All G71MPP filters are installed external to the unit. Filters

should be inspected monthly. Clean or replace the filters

when necessary to ensure proper furnace operation. Table

3 lists recommended filter sizes.

Exhaust and air intake pipes

Check the exhaust and air intake pipes and all connections

for tightness 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

Winterizing and Condensate Trap Care

1 - Turn off power to the unit,

2 - Have a shallow pan ready to empty condensate water.

3 - Remove the drain plug from the condensate trap and

empty water. Inspect the trap then reinstall the drain

plug and refill trap with water,

Cleaning Heat Exchanger

If cleaning the heat exchanger becomes necessary, follow

the below procedures and refer to figure 1 when disassem-

bling unit. Use papers or protective covering in front of fur-

nace while removing heat exchanger assembly.

1 - Turn off electrical and gas supplies to the furnace.

2 - Remove the upper and lower furnace access panels,

3 - Disconnect the 2-pin plug from the gas valve,

4 - Remove gas supply line connected to gas valve, Re-

move gas valve/manifold assembly,

5 - Remove sensor wire from sensor, Disconnect 2-pin

plug from the ignitor.

6 - Disconnect wires from flame roll-out switches.

7 - Remove burner box cover and remove four burner box

screws at the vestibule panel and remove burner box,

Set burner box assembly aside.

NOTE -G71MPP-135 units are secured to the vesti-

bule panel by two additional screws. These screws

must be removed for servicing; however it is not nec-

essary to replace the screws.

NOTE- If necessary, clean burners at this time. Follow

procedures outlined in Burner Cleaning section.

8 - Loosen three clamps and remove flexible exhaust tee.

9 - Remove 3/8 inch rubber cap from condensate drain

plug and drain. Replace cap after draining.

10 - Disconnect condensate drain line from the conden-

sate trap, Remove condensate trap (it may be neces-

sary to cut drain pipe), Remove screws that secure

condensate collars to either side of the furnace and re-

move collars. Remove drain tubes from cold end

header collector box.

11 - Disconnect condensate drain tubing from flue collar,

Remove screws that secure both flue collars into

place. Remove flue collars, It may be necessary to cut

the exiting exhaust pipe for removal of the fittings,

12 - Mark and disconnect all combustion air pressure tub-

ing from cold end header collector box.

13 - Mark and remove wires from pressure switches. Re-

move pressure switches, Keep tubing attached to

pressure switches,

14 - Disconnect the 4-pin plug from the combustion air in-

ducer, Disconnect the two wires to the backup secon-

dary limit, if applicable. Remove four screws which se-

cure combustion air inducer to collector box, Remove

combustion air inducer assembly, Remove ground

wire from vest panel.

15 - Remove electrical junction box from the side of the fur-

nace.

16 - Mark and disconnect any remaining wiring to heating

compartment components. Disengage strain relief

bushing and pull wiring and bushing through the hole

in the blower deck.

17 - Remove the primary limit from the vestibule panel.

18 - Remove two screws from the front cabinet flange at

the blower deck. Spread cabinet sides slightly to allow

clearance for removal of heat exchanger.

Page 57

19- Removescrewsalongvestibulesidesand bottom

whichsecurevestibulepanelandheatexchangeras-

semblyto cabinet.Removetwoscrewsfromblower

railwhichsecurebottomheatexchangerflange,Re-

moveheatexchangerfromfurnacecabinet,

20- Backwashheatexchangerwithsoapywatersolution

orsteam,If steamis usedit mustbebelow275°F

(135°C).

21 - Thoroughly rinse and drain the heat exchanger. Soap

solutions can be corrosive, Take care to rinse entire

assembly.

22 - Reinstall heat exchanger into cabinet making sure that

the clamshells of the heat exchanger assembly are

resting on the support located at the rear of the cabi-

net. Remove the indoor blower to view this area

through the blower opening,

23 - Re-secure the supporting screws along the vestibule

sides and bottom to the cabinet,

24-Reinstall cabinet screws on front flange at blower

deck.

25 - Reinstall the primary limit on the vestibule panel.

26 - Route heating component wiring through hole in blow-

er deck and reinsert strain relief bushing,

27 - Reinstall electrical junction box.

28 - Reinstall the combustion air inducer. Reconnect the

4-pin plug to the wire harness. Reconnect the two

wires to the backup secondary limit, if applicable,

29 - Reinstall pressure switches and reconnect pressure

switch wiring.

30 - Carefully connect combustion air pressure switch hos-

ing from pressure switches to proper stubs on cold end

header collector box,

31 - Reinstall condensate collars on each side of the fur-

nace. Reconnect drain tubing to collector box,

32 - Reinstall condensate trap on same side as exhaust

pipe. Reconnect condensate drain line to the conden-

sate trap.

33 - Use securing screws to reinstall flue collars to either

side of the furnace. Reconnect exhaust piping and ex-

haust drain tubing,

34 - Replace flexible exhaust tee on combustion air induc-

er and flue collars, Secure using three existing hose

clamps,

35 - Reinstall burner box assembly in vestibule area,

36 - Reconnect flame roll-out switch wires.

37 - Reconnect sensor wire and reconnect 2-pin plug from

ignitor,

38 - Secure burner box assembly to vestibule panel using

four existing screws. Make sure burners line up in

center of burner ports.

39- Reinstall gas valve manifold assembly, Reconnect

gas supply line to gas valve,

40 - Reinstall burner box cover,

41 - Reconnect 2-pin plug to gas valve,

42 - Replace the blower compartment access panel.

43 - Refer to instruction on verifying gas and electrical con-

nections when re-establishing supplies.

44 - Follow lighting instructions to light and operate fur-

nace for 5 minutes to ensure that heat exchanger is

clean and dry and that furnace is operating properly.

45 - Replace heating compartment access panel,

Cleaning the Burner Assembly

1 - Turn off electrical and gas power supplies to furnace,

Remove upper and lower furnace access panels,

2 - Disconnect the 2-pin plug from the gas valve,

3 - Disconnect the gas supply line from the gas valve, Re-

move gas valve/manifold assembly.

4 - Mark and disconnect sensor wire from the sensor. Dis-

connect 2-pin plug from the ignitor at the burner box.

5 - Remove burner box cover and remove four screws

which secure burner box assembly to vest panel, Re-

move burner box from the unit.

NOTE -G71MPP-135 units are secured to the vesti-

bule panel by two additional screws. These screws

must be removed for servicing, however it is not nec-

essary to replace the screws.

6 - Use the soft brush attachment on a vacuum cleaner to

gently clean the face of the burners, Visually inspect

the inside of the burners and crossovers for any block-

age caused by foreign matter, Remove any blockage.

7 - Reconnect the sensor wire and reconnect the 2-pin

plug to the ignitor wiring harness.

8 - Reinstall the burner box assembly using the existing

four screws. Make sure that the burners line up in the

center of the burner ports.

9 - Reinstall the gas valve manifold assembly, Reconnect

the gas supply line to the gas valve, Reinstall the burn-

er box cover.

10 - Reconnect 2-pin plug to gas valve,

11 - Replace the blower compartment access panel.

12 - Refer to instruction on verifying gas and electrical con-

nections when re-establishing supplies.

13- Follow lighting instructions to light and operate fur-

nace for 5 minutes to ensure that heat exchanger is

clean and dry and that furnace is operating properly.

14 - Replace heating compartment access panel,

Page 58

Press the diagnostic push button and hold it to cycle through a menu of options. Every five seconds a new menu item will be

displayed. Release the button when the desired mode is displayed.

When the solid "E" is displayed, the control enters the Error Code Recall mode. Error Code Recall mode menu options: No change (dis-

playing error history) remains in Error Code Recall mode; solid "-="exits Error Code Recall mode; and solid "c" clears the error history. Must

press button while flashing "c" is displayed to clear error codes.

When the solid "-" is displayed, the control enters the Field Test mode. Field Test mode menu options: Solid "C" starts pressure switch

calibration; blinking "-" exits Field Test mode.

Flash Code Diagnostic Code /Status of Furnace

•Idle mode (Decimal blinks at 1 Hz 1/2 sec. On and 1/2 sec. Off

A CFM Display (1 sec. On 1/2 sec Off, CFM value)

C Staged Cooling (1 sec. On 1/2 sec. Off or 2 Stage 1 sec. pause CFM pause, Repeat codes)

d Dehumidification Mode (1 sec. On 1 sec Off, CFM, Pause Repeat Codes)

h Variable Capacity Heat (1 sec On 1/2 sec Off % of input rate Pause CFM Pause Repeat Codes)

H Staged Heat (1 sec On 1/2 sec Off or2 Stage 1 sec, CFM Pause Repeat Codes)

110 Low Line Voltage

113 High Line Voltage

115 Low 24V (control will restart if the error recovers)

125 Control failed self check, internal error, failed hardware. Control will restart if error recovers

180 Outdoor Air Sensor Failure - no error if just disconnected, only show if shorted or out of range

200 Rollout circuit open or previously opened

201 Circulator /COM failure _ unable to communicate w /circulating motor (blower)

202 Circulating motor /resistor mis-match or resistor missing

204 Gas Valve Miswired _ Resume normal operation after error corrected

223 Low Pressure Switch Failed Open

224 Low Pressure Switch Failed Closed

225 High Pressure Switch Failed Open

226 High Pressure Switch Failed Closed

227 Low Pressure Switch Opened during TFI or Run mode

228 Unable to perform successful pressure switch calibration mode

240 Low Flame Mode - Run Mode

241 Flame sense out of sequence _flame still present

250 Limit switch circuit open

270 Watchguard - Exceed maximum number of retries. No flame current sensed

271 Watchguard - Exceed maximum number ignition retries where the last retry was due to pressure switch

openin 9

272 Watchguard - Exceed maximum number of recycles where the last recycle was due to pressure switch

opening

273 Watchguard - Exceed maximum number of recycles where the last retry was due to flame failure

274 Watchguard - The limit remained open longer than 3 minutes

275 Watchguard - Flame sensed out of sequence; flame signal gone

290 Ignitor circuit Fault - failed ignitor or triggering circuitry

291 Restricted airflow - available CFM below min. firing rate

292 Circulator motor unable to start (seized bearings, stuck wheel, etc)

294 Inducer motor amp draw too high

310 Discharge air sensor failure - no error if just disconnected, only show if shorted or out of range

311 Restricted airflow heating mode - target input rate reduced to match available circulator CFM

312 Restricted airflow cooling or continuous fan mode - information only

Page 59

IGNITION AND CALL FOR LOW FIRE WITH TWO-STAGE

THERMOSTAT

_ [ Safety ]q

Check

Verify There ]

Is No Main Burner

Flame

YES

.. [De-Energ,ze

Circuit NO--I_- Gas Valve

YES

Indoor blower OFF After

Heat OFF Delay YES

Inducer On NO

GaoVa,vej, {100°,orate O._100°,o_r_:::_:_ B

L s_eed/ "_ _o_,o_

Air Inducer

On (100% r soft Lockout:

rate speed) YES L Error Code

Flashes

Indoor Blower

ON (7O%)

[

YES

__ i

YES

Combustion Air

Inducer ON at 70%

Rate Speed

No-[Pre_GtSo_,r

YES I

I Pre-Purge I

-- 15 Seconds ,

-I,onitorONI"

20 Second_

I Gas ValveEnergized I

L Interpurge(15 Seconds) I

_ No

I Ignition Trial Begin_ Indoor Btower Delay I I

(Ignit/r ON) /I Timer Started I .[

Gas Valve

NO De-energized YES Post-Purge _'1

, oseconds,

YES

I Ignitor OFF

I stW;ii',izF°tri°_%tiei_YI

Set Target Firing Rate

Signals Present

..... Based on Thermostat

Call For Heat Satisfied

Error Code Flashes Indoor Blower OFF After

After 5Seconds I I Heat OFF Delay I

Switch Opens Error Code

Flashes

Call For 2nd Stage Heat

4_ NO_

YES

Soft Lockout:

Error Code

Flashes

Combustion I_[Soft Lockout: ]

Air Inducer Error Code

OFF Flashes

Heat p

-Z_ SOFT LOCKOUT IS RESETAUTOMATICALLYAFTER ONE HOUR WITH ACALL FOR HEAT ACTIVE,_

Page 60

CALL FOR HIGH FIRE WITH TWO-STAGE THERMOSTAT

I 2 StageThermostat

YES NO

Combustion Air Inducer ON I

(100% Rate Speed)

_ NO---_

YES

Adjust Indoor

B}ower to

Appropiate speed

Wait for Catl for Heat Satisfied

Increase Combustior

Air Inducer Speed

if Not at 100%

Rate Speed

System will always light at 70% even if 2nd stage call for heat is in place

,_ If the high pressure switch does not close within 5 attempts, the system

will operate at low fire for the remainder of the call for heat at request

Page 61

CALLFOR HEAT SATISFIED

RUN MODE (TWO-STAGE THERMOSTAT)

FIRST OR SECOND-STAGE CALL FOR HEAT

ALL INPUTS MONITORED (LIMIT, PRESSURE,

CALL FOR HEAT/COOL, FLAME LEVEL).

2nd Stage Heat I._NO

L. Call for Heat_

YES

I Combustion Air Inducer

sw tched to 70% rate speed

I_0i_s_'_0oo_'owe_Ito appropiate speed

---/

YES

Gas valve

De-Energized

Combustion Air Inducer OFF I

after 20-Second Post Purge I

after OFF Delay

Wait for Call Wait for Call

Two-Stage Single-Stage

Thermostat Thermostat

_ RUN MODE (SINGLE-STAGE THERMOSTAT)

ALL INPUTS MONITORED (LIMIT, PRESSURE,

CALL FOR HEAT/COOL, FLAME LEVEL).

Page 62

IGNITION AND CALL FOR HEAT WITH SINGLE-STAGE THERMOSTAT

--- [ Safety 19Check

Verify There

Is No Main Burner

Flame

YES

Indoor Blower OFF After

Heat OFF Delay

(Low Heat Speed)

De-Energize LJcombustion Air_

Gas Valve Inducer ON

YES

Indoor Blower _

ON NO_

(100% Speed)

J _ I Indoor Btower OFF

After Heat OFF Delay

H gh HeaiSpeed

YES

ac I°gr_libtiUoS_iO_ 7A0r°/lonrdat c erp e%Nd

_ N°" I Calibration

t_ NO

]

YES

Pre-Purge

--I 15Sec°ndsI

I 'g°it°r I"20 Seconds

I GasVaiveEnergized I

÷ ÷

IgnitionTdal Begins Indoor Blower On I

I Ignit/rON II Delay Timer Started I /[

_NO_ D eG-aSlerVaIgiVzeed _Stches s_fu Y ES _-[

YES

I IgnitorOFF I

I Wait For IgnitionStabilization Delay I

I Set to I

.... Low Firing Rate I

Move to Mid Firing Rate

and High Firing Rate after /qR _,Call For Heat Satisfied

I 2nd and 3rd Stage Delays I \_J

I (based on DIP Switch selections) I_

Soft Lockout:

Error Code

Flashes

Post-Purge H Combustion Air]_(20 Seconds) Inducer OFF

Interpurge(15 Seconds) ]

YES

YES NO

IA/nedr_H;aE_oWF_FOF,F

Soft Lockout:

Error Code

Flashes Z_

:SOFT LOCKOUT IS RESETAUTOMATICALLYAFTER ONE HOUR WITFACALL FOR HEAT ACTIVE

HC:R: LCoYcE:IobG IqH: ECsAErL:: :yHcL i%: :O_W: :C:l :HGEPcOoV_ETRRToOL:HE CONTROL.

Page 63

CALLFOR COOLING

1st Stage Cooling

Request Received

Energize 1st Stage

Cooling Contactor

Compressor & Fan

A_tned°2°-rseE_c°W_rdO'naYI

Energize Indoor Blower A_

Per Ramp ng Prof e z_\

4 YES

_'_YES-- --YES'_

Energize 2nd Stage I ,[Energize Indoor BlowerCooling Contactor I(High Cooling mode)

(Compressor & Fan) NO

I I

_ES__%n:%_,dn;':&%er1

De-Energize 2nd I

Stage Cooling I

Contactor

(Compressor & Fan)l

Energ,zeand,

MaLnt:nclonodiOlCgrB_oOdVratJ

De-Energize 1st I

Stage Cooling I

Contactor

(Compressor & Fan)I

IDe-Energize'nd°°rBl°wer

Per Ramping Profile

2nd stage cooling operation requires a 2-stage thermostat, a 2-stage cooling system and

on-board link W915 must be be cut. The control will not respond to a 2nd stage cooling

request unless a 1st stage cooling request is active

Indoor blower cooling mode and high cooling mode have a specific ON, OFF and speed

ramping profiles. The specific profile is selected using the DIP switches on the control.

Page 64

CONTINUOUSLOW SPEED INDOOR BLOWER SEQUENCE OF OPERATION

Call for

Continuous Blower

Indoor Blower On |

(Speed Determined b_

Dip Sw tch set ings)|

Maintain Indoor

YES,-I_ Blower at set speed _(_ Go to Call for Cooling

'_" |"'_0 Go to Call for Heat -- Two-Stage Thermostat

for Heat _)-YES._ Maintain indoor OR

| Blower at set speed

,,,,l_l 4 )Go to Call for Heat -- Single-Stage Thermostat

Maintain Indoor

NO,,--Ip. Blower at set speed

YES

De-Energize I'_

indoor Blower Per

Ramping Profile

_\ indoor blower low cooling mode and high cooling mode, have specific ON - OFF and speed

ramping profiles. The specific profile is selected using the dip switches on the control.

Page 65

ThefollowingrepairpartsareavailablethroughLennoxdealers.Whenorderingparts,includethecompletefurnacemodel

numberlistedontheCSAnameplate-- Example:G71MPP-36B-070-7,All servicemustbeperformedby a licensed

professional installer (or equivalent), service agency, or gas supplier.

Cabinet Parts

Upper access panel

Blower access panel

Top cap

Control Panel Parts

Transformer

Integrated control

Door interlock switch

Circuit breaker

Blower Parts

Blower wheel

Motor

Motor mounting frame

Power choke (1 hp only)

Blower housing cut-off plate

Heating Parts

Flame sensor

Heat exchanger assembly

Gas manifold

Combustion air inducer

Gas valve

Main burner cluster

Main burner orifices

Pressure switches

Ignitor

Primary limit control

Secondary limit control

Flame rollout switches

Combustion air inducer auxiliary limit

H-fitting pressure switch assembly

Job Name Job No, Date

Job Location

Installer

Unit Model No.

Serial No.

City

Technician

State

Heating Section

Electrical Connections Tight?

Supply Voltage

Blower Motor Amps []

Fuel Type: Natural Gas? []

Furnace Btu Input

Line Pressure

[] Blower Motor H,P.

Gas Piping Connections

Tight & Leak-Tested?

LP/Propane Gas? []

Regulator Pressure __ w,c, - Nat,:

Flue Connections Tight? []

Condensate Connections Tight? []

Combustion Gas Tested? [] CO2 [] CO

Fan Control Setting

(45 Seconds Fixed On)

Fan Control Off Setting

Filter Clean & Secure? []

Thermostat

Calibrated? []

w,c, - LP/Propane

Proper Draft? []

Temperature Rise

Vent Clear? []

Heat Anticipator Properly Set? []

Level? []

Page 66

LENNOX Furnace/Heater, Gas Manual L0806234

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