Lennox G40UH-36A-045, G40UH-36A-070, G40UH-36B-090, G40UH-48B-070, G40UH-48B-090 Installation Instructions Manual

_p

LEIVIVDX T

C(92006Lennox Industries Inc.

Dallas, Texas, USA

RETAIN THESEINSTRUCTIONS

FOR FUTURE REFERENCE

INSTALLATION
INSTRUCTIONS

G40UH(X) Series

GAS FURNACE F]_-_ Technical

505,252M _L._L Publications

08/2006
Supersedes 505,181M Lithe U.S.A.

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

G40UH(X) Parts Arrangement .................... 3

G40UH(X) Gas Furnace .......................... 4

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

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

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

Combustion, Dilution & Ventilation Air .............. 5

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Start-Up & Performance Check List ................ 34

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.

08/06

IIIIIIIIIIIIIIIIIIIIIIIIIIIIHI]IIIIII

-&WARNING

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.

505,252M

Page1 IIIllllll]lllllllll]lllllllll]llllllllll

*NOTE - 60C and 60D units that require air volumes
over 1800 cfm (850 L/s) must have one of the following:

1.Return air from single side with transition which will
accommodate 20 x 25 x 1 in. (508 x 635 x 25 mm)
cleanable air filter. (Required to maintain proper air
velocity.)

2. Return air from single side with optional RAB Return
Air Base.

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.

**Flue outlet may be horizontal but furnace must be
vented vertically

_Optional external side return air filter kit cannot be used

with the optional RAB Return Air Base.

',9-9/16 (14)

_OPTIONAL

EXTERNAL

SIDE RETURN

AIR FILTER KIT

(Either Side)

(1016)

3-3/4 (95)-IP 1

r

D

FLUE OUTLET

(Top)

_OPTIONAL

EXTERNAL

SIDE RETURN

AIR FILTER KIT

(Either Side)

TOP VIEW

3-1/4 (83) Right I_ 28-1/2

8-1/8 (206)Left /3-3/,L

14 (356) Right

13-1/4 (337) Left

4-7/8 (124) Right

40

2-1/4 (57) Left -I_

/

-_ (95)

-- 25 (635)

TOP VIEW

(724) "_

_,91._ 19-7/16 ._ID,,_

/ (494) 1

9/16

91-(14)

14-3/4

3/4 (19) -I_

G40UH-24A-045,
G40UH-24A-070, 368 13-3/8 340 13 114

G40UH-36A-045,
G40UH-36A-070

G40UH-36B-090,
G40UH-48B-070, 446 16-3/8 416 16 152

G40UH-48B-090
G40UH-36B-110,

G40UH-48C-110, 533 19-7/8 454 19-1/2 197
G40UH-48C-135,

G40UH-60C-110
G40UH-60D-135 622 23-3/8 546 23 241

G40UH-60D-155

,q_-i C m

*Bottom Return

Air Opening

FRONT VIEW

Model No.

_1__1- 3/4 (19)

A B C

in.

14-1/2

17-1/2

21

24-1/2

(375)

(406)

5/8(16)

23-1/2 y

4-1/4

(108)

mm in. mm in. mm

Page 2

(597)

*Bottom Return

Air Opening

SIDE VIEW

D

mm in

330 4-1/2

406 6

495 7-3/4

584 9-1/2

FlueBoxGasket /

Deflector

G40UH-48C-135,

G40UH-60C-110, &

G40UH-60D-155

Units Only

Gasket

Flue Transition

/

Flame Sensor _ I

Flame Rollout Switches* i

Flame Rollout Bracket

Gas Valve

Heat Excha _._...

Flue Collector Box

Combustion Air

Orifice

Combustion Air

Pressure Switch

Inducer

Limit Shield

Primary Limit

NOx Insert

(NO x Units Only'

Gas Orifices

Igniter Bracket Igniter

Burner Bottom Shield

Control Transformer

"135 and 155 kBtuh units only --

Flame rollout switches are located

on the left and one on the right) of
the burner box.

on brackets on the inner sides (one J "_

Integrated Ignition

Control Board

"4_

\

Secondary Limit

Blower Assembly

_ Capacitor

Door Interlock Switch

FIGURE 1

Page 3

TheG40UH(X)gasfurnaceisshippedreadyforinstalla-
tionin theupfiowandhorizontalposition(leftor right)

fueledbynaturalgas.Aconversionkit(orderedseparate-
ly)isrequiredforuseinpropane/LPgasapplications.The

furnaceisshippedwiththebottompanelinplace.Thebot-
tompanelmustberemovediftheunitistobeinstalledina

horizontalapplication.Thepanelmayalsoberemovedin
upfiowapplications.

Package 1 of 1 contains

1 - Assembled G40UH(X) unit
1 - Bag assembly containing the following:

2 - Screws
3 -Wire nuts

1 - Snap bushing
1 - Snap plug

1 - Wire tie
1 -Vent warning label

1 -Owner's manual and warranty card

The following items may also be ordered separately:

1- Thermostat
1 - Hanging bracket (for horizontal installations)

1 - Propane/LP changeover kit

Check equipment for shipping damage. If you find any
damage, immediately contact the last carrier.

.WARNING

&,CAUTION

G40UH(X) units are CSA International certified to ANSI
Z21.47 and CSA 2.3 standards.

In the USA, installation of gas furnaces must conform with lo-
cal building codes. In the absence of local codes, units must

be installed according to the current National Fuel Gas Code
(ANSI-Z223.1). 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 CSA
B149 Natural Gas and Propane Installation Codes, local

plumbing or waste water codes and other applicable local
codes.

Adequate clearance must be made around the air open-
ings into the vestibule area. In order to ensure proper unit

operation, combustion and ventilation air supply must be
provided according to the current National Fuel Gas Code

or CSA B149 standards.
Vent installations must be consistent with the venting

tables (in this instruction) and applicable provisions of local
building codes.
This furnace is CSA Intemational certified for installation

clearances to combustible material as listed on the unit
nameplate and in the tables in figures 6 and 11.Accessibility

and service clearances must take precedence over fire
protection clearances.

NOTE- For installation on combustible floors, the furnace
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 garage, hangar, or other building that has a haz-
ardous atmosphere, the furnace must be installed accord-

ing to recommended good practice requirements and cur-
rent National Fuel Gas Code or CSA B149 standards.

NOTE - Furnace must be adjusted to obtain a temperature
rise within the range specified on the unit nameplate. Failure
to do so may cause erratic limit operation and premature heat

exchanger failure.

This G40UH(X) furnace must be installed so that its electri-
cal components are protected from water.

When this furnace is used with cooling units, it shall be
installed in parallel with, or on the upstream side of, cooling

units to avoid condensation in the heating compartment.
With a parallel flow arrangement, a damper (or other means

to control the flow of air) must adequately prevent chilled air
from entering the furnace. If the damper is manually oper-

ated, 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.

Page 4

NOTE - This furnace is designed for a minimum continu-
ous return air temperature of 60°F (16°C) or an intermit-
tent operation down to 55°F (13°C) dry bulb for cases
where a night setback thermostat is used. Return air tem-

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

NOTE - G4OUH(X) series units should not be installed as
a unit heater.

• 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.

The G40UH(X) furnace may be installed in alcoves, clos-
ets, attics, basements, garages, and utility rooms in the up-

flow or horizontal position.

This furnace design has not been CSA International certi-

fied for installation in mobile homes, recreational vehicles,

or outdoors.
Lennox does not recommend the use d G40UH(X) 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.

G40UH(X) 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

allowed.

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

• Return air temperature range between 60°F (16°C) and
80°F (27°C) must be maintained.

• Air filters must be installed in the system and must be
maintained during construction.

• Air filters must be replaced upon construction comple-
tion.

• The input rate and temperature rise must be set per the
furnace rating plate.

• One hundred percent (100%) outdoor air must be pro-
vided for combustion air requirements during construc-
tion. Temporary ducting may supply outdoor air to the
furnace. Do not connect duct directly to the furnace.
Size the temporary duct following these instructions in
section for Combustion, Dilution and Ventilation Air in a
confined space with air from outside.

• The furnace heat exchanger, components, duct system,
air filters and evaporator coils must be thoroughly
cleaned following final construction clean-up.

• All furnace operating conditions (including ignition, in-
put rate, temperature rise and venting) must be verified
according to these installation instructions.

NOTE - The Commonwealth of Massachusetts stipu-
lates these additional requirements:

These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.

In addition to the requirements outlined previously, the fol-
lowing general recommendations must be considered
when installing a G40UH(X) furnace:

• Place the furnace as close to the center of the air dis-
tribution system as possible. The furnace should also be

located close to the chimney or vent termination point.

• Do not install the furnace where drafts might blow direct-
ly into it. This could cause improper combustion and un-

safe operation.

• Do not block the furnace combustion air openings with
clothing, boxes, doors, etc. Air is needed for proper

combustion and safe unit operation.

• When the furnace is installed in an attic or other insu-
lated space, keep insulation away from the furnace.

,,WARNING

In the past, there was no problem inbringing in sufficient out-
door air for combustion. Infiltration provided all the air that
was needed. In today's homes, tight construction practices
make it necessary to bring in air from outside for combus-
tion. Take into account that exhaust fans, appliance vents,
chimneys, and fireplaces force additional air that could be

used for combustion out of the house. Unless outside air is
brought into the house for combustion, negative pressure

Page 5

(outsidepressureisgreaterthaninsidepressure)willbuild
tothepointthatadowndraftcanoccurinthefurnacevent
pipeorchimney.Asaresult,combustiongasesentertheliv-
ingspacecreatingapotentiallydangeroussituation.

Intheabsenceoflocalcodesconcerningairforcombus-
tionandventilation,usetheguidelinesandproceduresin
thissectiontoinstallG40UH(X)furnacestoensureefficient
andsafeoperation.Youmustconsidercombustionair

needsandrequirementsforexhaustventsandgaspiping.
Aportionofthisinformationhasbeenreprintedwithper-

missionfromtheNationalFuelGasCode(ANSI-Z223.1).
Thisreprintedmaterialisnotthecompleteandofficialposi-
tionoftheANSIonthereferencedsubject,whichisrepre-
sentedonlybythestandardinitsentirety.

InCanada,refertotheCSAB149installationcodes.

,&CAUTION

&CAUTION

All gas-fired appliances require air for the combustion pro-
cess. If sufficient combustion air is not available, the fur-
nace or other appliances will operate inefficiently and un-
safely. Enough air must be provided to meet the needs of all
fuel-burning appliances and appliances such as exhaust

fans which force air out of the house. When fireplaces, ex-
haust fans, or clothes dryers are used at the same time as
the furnace, much more air is necessary to ensure proper
combustion and to prevent a downdraft. Insufficient air
causes incomplete combustion which can result in carbon

monoxide.

In addition to providing combustion air, fresh outdoor air

dilutes contaminants in the indoor air. These contami-
nants may include bleaches, adhesives, detergents, sol-

vents and other contaminants which can corrode furnace
components.

The requirements for providing air for combustion and ven-
tilation depend largely on whether the furnace is installed in
an unconfined or a confined space.

Unconfined Space

An unconfined space is an area such as a basement or
large equipment room with a volume greater than 50 cubic
feet (1.42 m3) per 1,000 Btu (.29 kW) per hour of the com-
bined input rating of all appliances installed in that space.
This space also includes adjacent rooms which are not
separated by a door. Though an area may appear to be un-
confined, it might be necessary to bring in outdoor air for
combustion if the structure does not provide enough air by

infiltration. If the furnace is located in a building of tight
construction with weather stripping and caulking around

the windows and doors, follow the procedures in the air
from outside section.

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

bic feet (1.42 m3) per 1,000 Btu (.29 kW) per hour of the
combined input rating of all appliances installed in that
space. This definition includes furnace closets or small
equipment rooms.

When the furnace is installed so that supply ducts carry air
circulated by the furnace to areas outside the space con-
taining the furnace, the return air must be handled by ducts
which are sealed to the furnace casing and which terminate
outside the space containing the furnace. This is especially
important when the furnace is mounted on a platform in a
confined space such as a closet or small equipment room.

Even a small leak around the base of the unit at the platform
or at the return air duct connection can cause a potentially
negative pressure condition. Air for combustion and dan-
gerous ventilation can be brought into the confined space
either from inside the building or from outside.

Page 6

EQUIPMENT IN CONFINED

CHIMNEY

VENT

FURNACE 1_

I I I I I II I I I I I I II I I I
I I

SPACE ALL AIR FROM INSIDE

HEATER

OPENINGS

(To Adjacent

WiTER/

Room)

I I I I

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

inch (645 mm'_? per 1,000 Btu (. 29 kW) per hour of the total input rat-
ing of all equipment in the enclosure, but not less than !00 square
inches (64516 mm2).

FIGURE 2

Air from Inside

If the confined space that houses the furnace adjoins a
space categorized as unconfined, air can be brought in by
providing two permanent openings between the two
spaces. Each opening must have a minimum free area of 1
square inch (645 mm2) per 1,000 Btu (.29 kW) per hour of
total input rating of all gas-fired equipment in the confined
space. Each opening must be at least 100 square inches

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

mm) of the top of the enclosure and one opening within 12
inches (305 mm) of the bottom. See figure 2.

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

tion, the confined space must have two permanent open-
ings. One opening shall be within 12 inches (305 mm) of the

top of the enclosure and one opening within 12 inches (305
mm) of the bottom. These openings must communicate di-
rectly or by ducts with the outdoors or spaces (crawl or at-
tic) that freely communicate with the outdoors or indirectly
through vertical ducts. Each opening shall have a minimum
free area of 1 square inch (645 mm2) per 4,000 Btu (1.17
kW) per hour d total input rating of all equipment in the en-
closure. See figures 3 and 4. When communicating with
the outdoors through horizontal ducts, each opening shall
have a minimum free area of 1square inch (645 mm 2) per
2,000 Btu (.56 kW) per total input rating of all equipment in
the enclosure. See figure 5.
When ducts are used, they shall be of the same cross-sec-
tional area as the free area of the openings to which they
connect. The minimum dimension of rectangular air ducts
shall be no less than 3 inches (75 mm). In calculating free
area, the blocking effect of louvers, grilles, or screens must
be considered. Ifthe design and free area d protective cov-
ering is not known for calculating the size opening required,
it may be assumed that wood louvers will have 20 to 25 per-
cent free area and metal louvers and grilles will have 60 to
75 percent free area. Louvers and grilles must be fixed in the
open position or interlocked with the equipment so that they
are opened automatically during equipment operation.

EQUIPMENT IN CONFINED SPACE

ALL AIR FROM OUTSIDE

CHIMNEY OR

GAS VENT

VENTILATION LOUVERS

(Each end of attic)

I ...... I

FURNACE AIR WATER

VENTILATION INLET

LOUVERS AIR

(For unheated crawl ._

NOTE-The inlet and outlet air openings shall each have a free area of at least one square inch (645 mm2)

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

(Inlet Air from Crawlspace and Outlet Air to Ventilated Attic)

OUTLET

HEATER

FIGURE 3

Page 7

CHIMNEY

OR GAS

EQUIPMENT IN CONFINED SPACE

ALL AIR FROM OUTSIDE

(All Air Through Ventilated Attic)

VENTILATION LOUVERS

(Each end of attic)

The G40UH(X) gas furnace can be installed as shipped
in either the upflow position or the horizontal position,
with right-hand or left-hand air discharge,

Select a location that allows for the required clearances
that are listed on the unit nameplate, Also consider gas
supply connections, electrical supply, vent connection,
and installation and service clearances [24 inches (610
mm) at unit front], The unit must be level.

FURNACE

NO TE- The inlet and outlet air openings shall each have a
free area of at least one square inch (645 mm 2)per 4,000

Btu (1.17 kW) per hour of the total input rating of all equip-
ment in the enclosure.

INLET AIR

(Ends 12 in.

above bottom)

HEATER

FIGURE 4

A _ EQUIPMENT IN
TT'_. //_ CONFINED SPACE

I I "_"/ _ ALLAIRFROM

NOTE - 1/3 hp blower motors are equipped with four flex-
ible mounting legs, and 1/2 hp blower motors are equipped

with three flexible legs and one rigid leg. The rigid leg is
equipped with a shipping bolt and a flat white plastic wash-
er (rather than the rubber mounting grommet used with a
flexible mounting leg). The bolt and washer must be re-
moved before the furnace is placed into operation. Af-
ter the bolt and washer have been removed, the rigid leg

will not touch the blower housing.

Upflow Applications
Allow for clearances to combustible materials as indicated

on the unit nameplate, Minimum clearances for closet or al-
cove installations are shown in figure 6,

Upflow Application Installation Clearances

Top

Left Side

Right Side

,,,,i

NOTE - Each air duct opening shall have a free area of at least
o 2

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

the total input rating of all equipment in the enclosure. If the
equipment room is located against an outside wall and the air

openings communicate directly with the outdoors, each open-
ing shall have a free area of at least one square inch (645 mm2)

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

other equipment in the enclosure.

, l

FIGURE 5

AWARNING

Page 8

Bottom

Type of Vent

Connector

Top

*Front

Back

Sides

Vent
Floor

*Front clearance in alcove installation must be 24 in. (610 ram).
Maintain a minimum of 24 in. (610 ram) for front service access.

SFor installations on a combustible floor, do not install the furnace
directly on carpeting, tile or other combustible materials other
than wood flooring.
l-Left side requires 3 inches ifa single wall vent is used on 14-1/2
inch cabinets, or 2 inches if a single wall vent is used on 17-1/2

inch cabinets.

TypeC

1in, (25 ram)

3 in, (76 ram)

0

Ot

6 in. (152 ram)

05

Type B1

1 in, (25 ram)

3 in, (76 ram)

0
0

1 in, (25 ram)

0J;

FIGURE 6

Return Air -- Upflow Applications

Return air can be brought in through the bottom or either
side of the furnace installed in an upflow application. If the

furnace is installed on a platform with bottom return, make

an airtight seal between the bottom of the furnace and the
platform to ensure that the furnace operates properly and
safely. The furnace is equipped with a removable bottom
panel to facilitate installation,

Markings are provided on both sides of the furnace cabinet

for installations that require side return air. Cut the furnace

cabinet at the maximum dimensions shown on page 2.

NOTE - When air volumes over 1800 cfm (850 L/s) are
required with 60C or 60D models in an upflow applica-
tion, the following return air options are available:

1 - Return air from single side with transition which will

accommodate 20 x 25 x 1 in. (508 x 635 x 25 mm) clean-
able air filter. (Required to maintain proper air velocity.)

See figure 7.

2 - Return air from single side with optional RAB Return

Air Base. See figure 8.

3 - Return air from bottom.

4 - Return air from both sides.

5 - Return air from bottom and one side.

Refer to Engineering Handbook for additional information.

Side Return Air

(with transition and filter)

20" X 25" X 1"

(508mm X635mm X 25mm)

Cleanable Filter

_/

Return Air

Plenum

Transition

FIGURE 7

Optional Return Air Base

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

J

AIR FLOW

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

21 (533) RAB-C (98M58)

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

7-1/4 (184)

OPTIONAL RAB

RETURN AIR BASE

14

L

7/8

(22)

©

r

41

(102)1"9_-

123(584) fL_-

Overall 1 MinimuV_

(Maximum) 11 (279)

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

5-5/8

(143)

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

_1-- 27-5/8 (702)

SIDE VIEW

2 Maximurr

I

1 22-7-16

(570)

Overall

Maximum)

_2

_-- 3/4

FRONT VIEW

NOTE- Optional Side Return Air Filter Kits are not for use with RAB Return Air Base.
1 Both the unit return air opening and the base return air opening must be covered by a single plenum or IAQ cabinet.

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

(584 x 279 mm).
The opening can be cut as needed to accommodate plenum or IAQ cabinet while maintaining dimensions shown.
Side return air openings must be cut in the field. There are cutting guides stenciled on the cabinet for the side return
air opening. The size of the opening must not extend beyond the markings on the furnace cabinet..

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

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

(19)

FIGURE 8

Page 9

Removingthe Bottom Panel

Remove the two screws that secure the bottom cap to the
furnace. Pivot the bottom cap down to release the bottom
panel. Once the bottom panel has been removed, reinstall
the bottom cap, See figure 9.

Removing the Bottom Panel

Leveling Bolt Installation

3/8

(1o)_r

Furnace Front _ [

3/8 1-3/4

Inches (mm)

(44)

Screw

\/

Bottom Cap

Bottom

FIGURE 9

Leveling an Upflow Unit

When the side return air inlets are used in an upfiow ap-
plication, it may be necessary to install leveling bolts on the
bottom of the furnace. Use field-supplied corrosion-resist-
ant 5/16 inch machine bolts (4) and nuts (8), See figure 10,

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

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

ter hole in each corner of the furnace's bottom. See fig-
ure 10 for the correct location of the holes, Drill through

the bottom panel and the bottom flange of the cabinet.

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

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

NOTE - The unit may be tilted back-to-front a maximum of

1", This will ensure proper draining of the heat exchanger,

1-3/4

(44)

Furnace

Bottom

Leveling Bolts

3/8

(1o)

I-3/4 (44)

FIGURE 10

Horizontal Applications

The G40UH(X) furnace can be installed in horizontal ap-
plications,

Allow for clearances to combustible materials as indicated
on the unit nameplate, Minimum clearances for closet or al-

cove installations are shown in figure 11,

Horizontal Application

Installation Clearances

Top

Left End

Bottom

Vent Connector

Type Type C Type B1

Top 0 0

*Front 3 in. (76 ram) 3 in. (76 ram)

Back 0 0

Ends 2 in. (51 ram) 2 in. (51 ram)
Vent 6 in. (152 ram) 1 in. (25 ram)

Floor 05 05

*Front clearance in alcove installation must be 24 in. (610 ram).
Maintain a minimum of 24 in. (610 ram) for front service access.
:_For installations on a combustible floor, do not install the furnace
directly on carpeting, tile or other combustible materials other
than wood flooring.

FIGURE 11

Leveling Bolts

3/8

(10)

1-3/4

(44)

Right End

Page 10

Thisfurnacemaybeinstalledineitheranatticoracrawl-
space,Eithersuspendthefurnacefromroofraftersor

floorjoists,asshowninfigure12,orinstallthefurnaceon

aplatform,asshowninfigure13.Theunitmustbesup-
portedatbothendsandbeneaththeblowerdecktopre-
ventsagging,

NOTE -In horizontal applications, the unit must be lev-
el side to side. The unit may be tilted back to front a maxi-

mum of 1". This will ensure proper draining of the heat ex-
changer.

Typical Horizontal Application

Unit Suspended in Attic or Crawlspace

Leave sufficient clearance between rod and unit to
remove access panel.

///

Horizontal Application

Unit Installed on Platform

NOTE - Line contact is permis-

sible. See the unit nameplate for

clearances.

\

\

\

GAS

ENTRY

WORKING

PLATFORM

FIGURE 13

__VENT

PIPE

1/4 in. ROD

ANGLE

IRON

U-CHANNELS

FIGURE 12

NOTE - Heavy gauge perforated sheet metal straps
(plumbers' straps) may be used to suspend the unit from

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

pend the unit in this way, support must be provided for both

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

The straps must not interfere with the plenum or exhaust

piping installation. Securing screws should be 1/2 inch

from the top edge and 1-1/2 inch from the side edge in all
cases. Cooling coils and supply and return air plenums

must be supported separately.
NOTE - When the furnace is installed on a platform in a

crawlspace, it must be elevated enough to avoid water
damage and to allow the evaporator coil to drain.

Return Air -- Horizontal Applications

Return air can be brought in through the end of a furnace
installed in a horizontal application, The furnace is
equipped with a removable bottom panel to facilitate
installation, See figure 9,

&WARNING

a,WARNING

Page 11

Thisunitisnotequippedwithafilterorrack.Afield-pro-
videdhigh-velocityfilterisrequiredfortheunittooperate
properly.Table1listsrecommendedfiltersizes.

Afiltermustbeinplacewhenevertheunitisoperating.

TABLE 1

Furnace

Cabinet Size

14-1/2"
17-1/2"

21"

24-1/2"

Side Return

16X25X 1 (1)
16X25X 1 (1)

16X25X 1 (1)
16 X 25 X 1 (2)

Use industry-approved standards to size and install the
supply and return air duct system. This will result in a quiet

and low-static system that has uniform air distribution.

NOTE - Do not operate the furnace with an external static
pressure that exceeds 0.5 inches w.c. Higher external stat-

ic pressures may cause erratic limit operation.

Supply Air Plenum

Filter Size

Bottom Return

14X25X1 (1)
16X25X1 (1)

20X25X 1 (1)
24X25X 1 (1)

A 4-inch diameter flue transition is factory-installed on the
combustion air inducer outlet of all models. Modifying or

removing the flue transition will cause the unit to oper-

ate unsafely and will void the unit certification. The

vent connector does not require insulation.
The combustion air inducer may be rotated clockwise or

counterclockwise by g0° to allow for vertical vent dis-
charge. Remove the four mounting screws, rotate the as-
sembly (including the gasket), then reinstall the mounting
screws. See figure 14. Use the provided wire tie to bundle
the pressure switch wires with the inducer motor power
leads. Route the power leads away from any moving
parts to prevent damage to the wires.

Combustion Air Inducer

90 °

Flue Transition

(Do not remove

If the furnace is installed without a cooling coil, a removable
access panel must be installed in the supply air duct. The

access panel should be large enough to permit inspection
(either by smoke or reflected light) of the heat exchanger

for leaks after the furnace is installed. The furnace access
panel must always be in place when the furnace is operat-

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

Return Air Plenum
Return air must not be drawn from 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 ap-
pliance is operating in a room with negative pressure, the

flue products can be pulled back down the vent pipe and
into the room, This reverse flow of the flue gas may result

in incomplete combustion and the formation of carbon
monoxide gas. This toxic gas might then be distributed

throughout the house by the furnace duct system,
In upfiow applications, the 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 air-

tight seal between the bottom of the furnace and the plat-
form to ensure that the unit operates properly and safely.

Use fiberglass sealing strips, caulking, or equivalent seal-
ing 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,

Mounting Screws

(Remove)

Top Cap

Flue Outlet Hole

(Reattach

Cutout Here)

Power Leads

FIGURE 14

Optional Flue Outlet

Supply Air

Opening

(Top View)

Optional Flue Outlet

(Side View)

FIGURE 15

Page 12

Usesheetmetalshearstoremovethecutoutfromtheside
ofthecabinet.Usethetwoprovidedsheetmetalscrewsto
installthecutoutonthetopcaptocovertheoriginalflue

outletopening.Seefigure15.
TheG40UH(X)seriesunitsareclassifiedasfan-assisted

CategoryIfurnaceswhenverticallyventedaccordingto
thelatesteditionoftheNationalFuelGasCode(NFPA54/

ANSIZ223.1)intheUSAandthecurrentCSAB149Natu-

ralGasandPropaneInstallationCodesinCanada.Afan-
assistedCategoryIfurnaceisanapplianceequippedwith

anintegralmechanicalmeanstoeitherdraworforcecom-
bustionproductsthroughthecombustionchamberand/or
heatexchanger.

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

persede local codes. This furnace must be vented accord-

ing to all local codes these installation instructions, and the

provided venting tables in these instructions

The venting tables in this manual were extracted from the
National Fuel Gas Code (NFPA 54 / ANSI Z223.1 ) and are
provided as a guide for proper vent installation. Proper ap-
plication, termination, construction and location of vents
must conform to local codes having jurisdiction. In the ab-
sence d local codes, the NFGC serves as the defining doc-

ument.
Refer to the tables and the venting information contained in

these instructions to properly size and install the venting
system.

&IMPORTANT

,&WARNING

Use self-drilling sheet metal screws or a mechanical fas-
tener to firmly secure the vent pipe to the round collar of the

flue transition. If self-drilling screws are used to attach the
vent pipe, it is recommended that three be used. Drive one

self-drilling screw through the front and one through each
side of the vent pipe and collar, See figure 16.

Install the first vent connector elbow at a minimum of six
inches (152 mm) from the furnace vent outlet,
Venting Using a Masonry Chimney

The following additional requirements apply when a lined
masonry chimney is used to vent this furnace,

Masonry chimneys used to vent Category I central fur-
naces must be either tile-lined or lined with a listed metal

lining system or dedicated gas vent, Unlined masonry
chimneys are prohibited, See figures 17 and 18 for com-

mon venting,
A chimney with one or more sides exposed to the outside of
the structure is considered to be an exterior chimney.

An exterior masonry chimney that is not tile-lined must be
lined with B1 vent or a listed insulated flexible metal vent.

An exterior tile-lined chimney that is sealed and capped
may be lined with a listed uninsulated flexible metal vent,

If the existing chimney will not accommodate a listed metal
liner, either the chimney must be rebuilt to accommodate
one of these liners or an alternate approved venting meth-

od must be found.
Insulation for the flexible vent pipe must be an encapsu-

lated fiberglass sleeve recommended by the flexible vent
pipe manufacturer. See figure 17,

DO NOT insulate the space between the liner and the
chimney wall with puffed mica or any other loose gran-

ular insulating material

Common Venting Using Metal-Lined Masonry Chimney

SEALED

T MAX. LENGTH

*- SEE NOTE 1

BELOW,

EXTERIOR

CHIMNEY WITH

METAL

INER

VENT CONNECTION

VENT

PIPE

J

FURNACE

FLUE TRANSITIOP

COLLAR

FIGURE 16

Page 13

PERMANENTLY

SEALED FIREPLACE

OPENING

NOTE 1 - Refer to the provided venting tables for installations in the USA
and the venting tables in CSA-B149 for installations Canada.

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

used. Refer to the capacity requirements shown in the provided venting
tables for installations in USA and the venting tables in current CSA-

B149 for installations in Canada.

FIGURE 17

Common Venting Using Tile-Lined Interior Masonry Chimne

' and Combined Vent Connector

J

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

MINIMUM LENGTH = AS SHORT AS PRACTICAL.
FOR MAXIMUM LENGTH SEE NOTE TO LEFT

J

INTERIOR TILE=LINED
MASONRY CHIMNEY

NOTE - the chimney must be properly
sized per provided venting tables or

lined with listed metal lining system.

i e%%o n.se l a r ea.tcsA-B,,,for

OTHER

APPLIANCE

l_ sE_EENTTORow

Note - Either single-walled or double-walled vent connector may be used. Refer to the capacity requirements as shown in the pro-
vided venting tables for installations in USA and the venting tables in current CSA-B149 for installations in Canada.

FIGURE 18

Never connect a Category I appliance to a chimney that is

&IMPORTANT

servicing a solid-fuel appliance, If a fireplace chimney flue
is used to vent this appliance, the fireplace opening must

be permanently sealed.
A type B or listed chimney lining system that passes

through an unused masonry chimney flue is not considered
to be exposed to the outdoors,

General Venting Requirements

Vent all G40UH(X) furnaces according to these instruc-
tions:

A fan-assisted furnace may be commonly vented into an
existing lined masonry chimney if the following conditions

are met:

• The chimney is currently serving at least one drafthood
equipped appliance.

• The vent connectors and chimney are sized according
to the provided venting tables for the USA, and the ap-

propriate venting tables in the standards of CSA B149
Natural Gas and Propane Installation Codes in Canada

If type B1 double-wall vent is used inside a chimney, no oth-
er appliance can be vented into the chimney. The outer wall
of type B1 vent pipe must not be exposed to flue products.

A type B1 vent or masonry chimney liner shall terminate
above the roof surface with a listed cap or a listed roof as-
sembly according to the terms of their respective listings

and the vent manufacturer's instructions.
When inspection reveals that an existing chimney is not

safe for the intended purpose, it shall be rebuilt to conform
to nationally recognized standards, lined or relined with
suitable materials, or replaced with a gas vent or chimney
suitable for venting G40UH(X) series units. The chimney
passageway must be checked periodically to ensure that it

is clear and free of obstructions.
Do not install a manual damper, barometric draft regulator,

or flue restrictor between the furnace and the chimney.

1 - Vent diameter recommendations and maximum allow-

able piping runs are found in the provided venting tables
for the USA, and the appropriate venting tables in the

standards of CSA B149 Natural Gas and Propane
Installation Codes for Canada.

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

be less than the diameter specified in the provided
venting tables for the USA, and the appropriate venting
tables in the standards of CSA B149 Natural Gas and

Propane Installation Code for Canada.

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

chimney has a larger diameter or flow area than the
vent connector, use the vertical vent diameter to de-

termine the minimum vent capacity and the vent
connector diameter to determine the maximum vent

capacity, The flow area of the vertical vent, however,
shall not exceed 7 times the flow area of the listed ap-

pliance categorized vent area, drafthood outlet area or
flue collar area unless designed according to approved

engineering methods.

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

section of vertical vent or chimney shall not exceed 7
times the smallest listed appliance categorized vent

area, drafthood outlet area orflue collar area unless de-
signed according to approved engineering methods.

PERMANENTLY

SEALED FIREPLACE

OPENING

Page 14

5- Theentirelengthofsinglewallmetalventconnector

shallbe readilyaccessiblefor inspection,cleaning,
andreplacement.

6- Singleapplianceventingconfigurationswithzerolat-

erallengths(tables3and4),areassumedtohaveno
elbowsintheventsystem.Forallotherventconfigura-

tions,theventsystemisassumedtohavetwo90°el-
bows.Foreachadditional90°elboworequivalent(for
exampletwo45°elbowsequalone90° elbow)beyond

two,themaximumcapacitylistedintheventingtable
shouldbereducedby10%(0.90xmaximumlistedca-

pacity).

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

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

connectordiameterasfollows:

TABLE 2

Connector Diameter Maximum Horizontal

inches (mm) Connector Length feet (m)

3 (76) 4-1/2 (1.37)
4 (102) 6 (1.83)
5 (127) 7-1/2 (2.29)
6 (152) 9 (2.74)
7 (178) 10-1/2 (3.20)

_

If the common vertical vent is offset, the maximum
common vent capacity listed in the common venting
tables should be reduced by 20%, the equivalent of two

90° elbows (0,80 x maximum common vent capacity).
The horizontal length of the offset shall not exceed

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

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

least number of elbows and angles required to com-
plete the job. Route the vent connector to the vent us-

ing the shortest possible route.

10 - A vent connector shall be supported without any dips

or sags and shall slope a minimum of 1/4 inch (6.4 mm)
per linear foot (305 mm) of connector, back toward the

appliance.

11 - Vent connectors shall be firmly attached to the furnace

flue collars by self-drilling screws (three recom-

mended) or other approved means, except vent con-
nectors d listed type B vent material which shall be as-
sembled according to the manufacturer's instructions.
Joints between sections of single wall connector piping
shall be fastened by screws or other approved means.

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

pliances must be located in or pass through a crawl-
space or other areas which may be cold, that portion of

the vent connector shall be constructed of listed
double-wall type B vent material or material having

equivalent insulation qualities.

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

ings must be installed with the listed clearance to com-
bustible materials and be fire stopped according to lo-
cal codes, In absence of local codes, refer to NFGC

(Z223.1).

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

through any circulation air duct or plenum.

15 - Vent connectors serving Category I appliances shall

not be connected to any portion of mechanical draft
systems operating under positive pressure such as

Category III or IV venting systems.

16 -If vent connectors are combined prior to entering the

common vent, the maximum common vent capacity
listed in the common venting tables must be reduced by

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

common vent capacity).

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

large as the largest vent connector diameter.

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

two consecutive table size diameters over the size of
the draft hood outlet or flue collar outlet.

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

lator or flue restrictor between the furnace and the
chimney.

20 - When connecting this appliance to an existing dedicated

or common venting system, you must inspect the venting
system's general condition and look for signs of corro-
sion. The existing vent pipe size must conform to these
instructions and the provided venting tables for the USA,

and the appropriate venting tables in the standards of
CSA B149 Natural Gas and Propane Installation Codes
for Canada. If the existing venting system does not meet
these requirements, it must be resized.

Page 15

TABLE 3

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

Serving a Single Category I Appliance

Vent and Connector Diameter - D (inches)

Height Lateral 3 Inch 4 Inch 5 Inch 6 Inch

H L

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

0 0 78 0 152 0 251 0 375

6

8

10

15 5 22 65 30 130 39 219 49 330

20

30 10 27 70 37 150 48 262 59 405

2 13 51 18 97 27 157 32 232

4 21 49 30 94 39 153 50 227

6 25 46 36 91 47 149 59 223
0 0 84 0 165 0 276 0 415

2 12 57 16 109 25 178 28 263
5 23 53 32 103 42 171 53 255
8 28 49 39 98 51 164 64 247

0 0 88 0 175 0 295 0 447
2 12 61 17 118 23 194 26 289

5 23 57 32 113 41 187 52 280

10 30 51 41 104 54 176 67 267

0 0 94 0 191 0 327 0 502
2 11 69 15 136 20 226 22 339

10 29 59 40 121 51 206 64 315
15 35 53 48 112 61 195 76 301

0 0 97 0 202 0 349 0 540
2 10 75 14 149 18 250 20 377

5 21 71 29 143 38 242 47 367

10 28 64 38 133 50 229 62 351
15 34 58 46 124 59 217 73 337

20 48 52 55 116 69 206 84 322

0 0 100 0 213 0 374 0 587
2 9 81 13 166 14 283 18 432

5 21 77 28 160 36 275 45 421

15 33 64 44 141 57 249 70 389

20 56 58 53 132 66 237 80 374
30 NR NR 73 113 88 214 104 346

NOTE - Single appliance venting configurations withzero lateral lengths are assumed to have no elbows in the vent system. For all other
vent configurations, the vent system is assumed to have two 90° elbows. For each additional 90° elbow or equivalent (for example two 45 °

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

MIN MAX MIN MAX MIN MAX MIN MAX

Page 16

TABLE 4

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

Serving a Single Category I Appliance

Vent and Connector Diameter - D (inches)

Height Lateral 3 Inch 4 Inch 5 Inch 6 Inch

H L

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

0 38 77 59 151 85 249 126 373

6

8

10

15 5 51 63 75 128 102 216 144 326

20

30 10 NR NR 91 144 122 255 171 397

2 39 51 60 96 85 156 123 231
4 NR NR 74 92 102 152 146 225

6 NR NR 83 89 114 147 163 220
0 37 83 58 164 83 273 123 412
2 39 56 59 108 83 176 121 261

5 NR NR 77 102 107 168 151 252
8 NR NR 90 95 122 161 175 243

0 37 87 57 174 82 293 120 444
2 39 61 59 117 82 193 119 287

5 52 56 76 111 105 185 148 277

10 NR NR 97 100 132 171 188 261

0 36 93 56 190 80 325 116 499
2 38 69 57 136 80 225 115 337

10 NR NR 95 116 128 201 182 308
15 NR NR NR NR 158 186 220 290

0 35 96 54 200 78 346 114 537
2 37 74 56 148 78 248 113 375

5 50 68 73 140 100 239 141 363

10 NR NR 93 129 125 223 177 344
15 NR NR NR NR 155 208 216 325

20 NR NR NR NR 186 192 254 306

0 34 99 53 211 76 372 110 584
2 37 80 55 164 76 281 109 429

5 49 74 72 157 98 271 136 417

15 NR NR 115 131 151 239 208 377

20 NR NR NR NR 181 223 246 357
30 NR NR NR NR NR NR NR NR

NOTE - Single appliance venting configurations with zero lateral lengths are assumed to have no elbows in the vent system. For all other
vent configurations, the vent system is assumed to have two 90 ° elbows. For each additional 90° elbow or equivalent (for example two 45°

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

MIN MAX MIN MAX MIN MAX MIN MAX

Page 17

TABLE 5

Vent Connector Capacity

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

Serving Two or More Category I Appliances

Vent Connector

Height Rise 3 Inch 4 Inch 5 Inch 6 Inch

H R Appliance Input Rating in Thousands of Btu Per Hour

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

1 22 37 35 66 46 106 58 164

6 2 23 41 37 75 48 121 60 183

3 24 44 38 81 49 132 62 199
1 22 40 35 72 49 114 64 176

8 2 23 44 36 80 51 128 66 195

3 24 47 37 87 53 139 67 210
1 22 43 34 78 49 123 65 189

10 2 23 47 36 86 51 136 67 206

3 24 50 37 92 52 146 69 220
1 21 50 33 89 47 142 64 220

15 2 22 53 35 96 49 153 66 235

3 24 55 36 102 51 163 68 248
1 21 54 33 99 46 157 62 246

20 2 22 57 34 105 48 167 64 259

3 23 60 35 110 50 176 66 271
1 20 62 31 113 45 181 60 288

30 2 21 64 33 118 47 190 62 299

3 22 66 34 123 48 198 64 309

Vent and Connector Diameter - D (inches)

TABLE 6

Common Vent Capacity

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

Serving Two or More Category I Appliances

Vent

Height 4 Inch 5 Inch 6 Inch 7 Inch

H Appliance Input Rating in Thousands of Btu Per Hour

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

6 92 81 140 116 204 161 309 248

8 101 90 155 129 224 178 339 275
10 110 97 169 141 243 194 367 299
15 125 112 195 164 283 228 427 352
20 136 123 215 183 314 255 475 394
30 152 138 244 210 361 297 547 459

Common Vent Diameter - D (inches)

Page 18

TABLE 7

Vent Connector Capacity

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

Serving Two or More Category I Appliances

Vent Connector

Height Rise 3 Inch 4 Inch 5 Inch 6 Inch

H R Appliance Input Rating in Thousands of Btu Per Hour

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

I NR NR NR NR NR NR NR NR

6 2 NR NR NR NR NR NR 168 182

3 NR NR NR NR 121 131 174 198

1 NR NR 79 87 116 138 177 214

15 2 NR NR 83 94 121 150 185 230

3 NR NR 87 100 127 160 193 243

1 47 60 77 110 113 175 169 278

30 2 50 62 81 115 117 185 177 290

3 54 64 85 119 122 193 185 300

Vent and Connector Diameter - D (inches)

TABLE 8

Common Vent Capacity

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

Serving Two or More Category I Appliances

Vent

Height 4 Inch 5 Inch 6 Inch 7 Inch

H Appliance Input Rating in Thousands of Btu Per Hour

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

6 89 78 136 113 200 158 304 244
8 98 87 151 126 218 173 331 269

10 106 94 163 137 237 189 357 292

15 121 108 189 159 275 221 416 343
20 131 118 208 177 305 247 463 383
30 145 132 236 202 350 286 533 446

Common Vent Diameter - D (inches)

Removal of the Furnace from Common Vent

In the event that an existing furnace is removed from a
venting system commonly run with separate gas ap-
pliances, the venting system is likely to be too large to

properly vent the remaining attached appliances,
Conduct the following test while each appliance is operat-

ing and the other appliances (which are not operating) re-
main connected to the common venting system. If the
venting system has been installed improperly, you must
correct the system as indicated in the general venting re-
quirements section,

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

tem.

_

Inspect the venting system for proper size and horizontal

pitch, Determine that there is no blockage, restriction,
leakage, corrosion, or other deficiencies which could

cause an unsafe condition,

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

tween the space in which the appliances remaining
connected to the common venting system are located

and other spaces of the building. Turn on clothes dry-
ers and any appliances not connected to the common
venting system. Turn on any exhaust fans, such as
range hoods and bathroom exhausts, so they will oper-
ate at maximum speed. Do not operate a summer ex-
haust fan. Close fireplace dampers,

4 - Follow the lighting instructions, Turn on the appliance

that is being inspected. Adjust the thermostat so that
the appliance operates continuously,

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

test for leaks of flue gases at the draft hood relief open-
ing. Use the flame of a match or candle, or smoke from

a cigarette, cigar, or pipe,

6 - After determining that each appliance connected to the

common venting system is venting properly, (step 3)
return all doors, widows, exhaust fans, fireplace damp-
ers, and any other gas-burning appliances to their pre-
vious mode of operation,

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

ing tests, the common venting system must be modi-
fied to correct the problem,

Page 19

Resizethecommonventingsystemto theminimum
sizedeterminedbyusingtheappropriatetablesinap-
pendixG.(Theseareinthecurrentstandardsofthe
NationalFuelGasCodeANSIZ223.1intheUSA,and
theappropriateCategory1NaturalGasandPropane

appliancesventingsizingtablesinthecurrentstan-
dardsof theCSAB149NaturalGasandPropane
InstallationCodesinCanada.)

-&CAUTION

a,WARNING

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

tors such as length d run, number of fittings, and fur-
nace rating to avoid excessive pressure drop. Table 9
lists recommended pipe sizes for typical applications,

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

clothes chutes, gas vents or chimneys, dumb waiters,
or elevator shafts.

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

feet (4,57 m) upward toward the meter from the fur-
nace. The piping must be supported at proper intervals
[every 8 to 10 feet (2.44 to 3.01 m)] with suitable hang-
ers or straps, Install a drip leg inside vertical pipe runs

to the unit,

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

a manual main shut-off valve and union (furnished by
the installer) external to the unit, The union must be of
the ground joint type.

&IMPORTANT

Gas Supply

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

lation of gas piping (or top entry in horizontal applica-
tions). Connect the gas supply to the piping assembly.

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

Nominal Internal

Iron Pipe Diameter

Size inches

inches (mm)

(ram)

3/8

(9.53)

1/2

(12.7)

3/4

(19.05)

1

(25.4)

1-1/4

(31.75)

1-1/2

(38.1)

2

(50.8)

2-1/2

(63.5)

3

(76.2)

NOTE - Capacity given in

.493 95 65

(12.522) (2.69) (1.84)

.622 175 120

(17.799) (4.96) (3.40)

.824 360 250

(20.930) (10.19) (7.08)

1.049 680 465

(26.645) (919.25) (13.17)

1.380 1400 950

(35.052) (39.64) (26.90)

1.610 2100 460

(40.894) (59.46) (41.34)

2.067 3950 2750

(52.502) (111.85) (77.87)

2.469 6300 4350

(67.713) (178.39) (123.17)

3.068 11000 7700

(77.927) (311.48) (218.03)

10 20 30 40 50 60 70 80 90 100

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

52

(1.47)

97

(2.75)

2OO

(5.66)

375

(10.62)

77O

(21.80)

1180

(33.41)

2200

(62.30)

3520

(99.67)

6250

(176.98)

cubic feet (m 3) of gas per hour and based

(1.27)

(2.32)

17O

(4.81)

32O

(9.06)

66O

(18.69)

990

(28.03)

1900

(53.80)

3000

(84.95

5300

(150.07)

NOTE - Install a 1/8inch NPT plugged tap in the field piping
upstream of the gas supply connection to the unit. The tap
must be accessible for test gauge connection. See figure 19.

NOTE - If emergency shutoff is necessa04 shut off the main
manual gas valve and disconnect main power to the fur-
nace. The installer should properly label these devices.

TABLE 9

Length of Pipe -feet (m)

45

82

4O

(1.13)

73

(2.07)

151

(4.28)

285

(8.07)

580

(16.42)

9OO

(25.48)

1680

(47.57)

2650

(75.04)

4750

(134.50)

on O.60 specific gravity gas.

36

(1.02)

66

(1.87)

138

(3.91)

26O

(7.36)

53O

(15.Ol)

81o

(22.94)

1520

(43.04)

2400

(67.96)

4300

(121.76)

33

(.73)

61

(1.73)

125

(3.54)

24O

(6.80)

490

(13.87)

75O

(21.24)

1400

(39.64)

2250

(63.71)

3900

(110.43)

31

(.88)

57

(1.61)

118

(3.34)

22O

(6.23)

46O

(13.03)

690

(19.54)

1300

(36.81 )

2050

(58.05)

3700

(104.77)

29

(.82)

53

(1.50)

110

(3.11)

2O5

(5.80)

430

(12.18)

65O

(18.41)

1220

(34.55)

1950

(55.22)

3450

(97.69)

27

(.76)

5O

(1.42)

103

(2.92)

195

(5.52)

400

(11.33)

62O

(17.56)

1150

(32.56)

1850

(52.38)

3250

(92.03)

Page 20

MANUAL

MAIN SHUT-OFF

VALVE

(With 1/8 in. NPT

Plugged Tap Shown)

GROUND

JOINT

UNION

Left Side Piping

(Standard)

AUTOMATIC

GAS VALVE
(with manual

shut-off valve /

AUTOMATIC MANUAL

GAS VALVE

(with manual VALVE

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

Shown)

JOINT

UNION

DRIP LEG

PROVIDED

DRIP LEG

AND INSTALLED

FIGURE 19

Leak Check

After gas piping is completed, carefully check all piping

connections (factory- and field-installed) for gas leaks, Use
a leak detecting solution or other preferred means,

NO TE - If emergency shutoff is necessarj4 shut off the main
manual gas valve and disconnect the main power to the

furnace, The installer should properly label these devices,

ACAUTION

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.).

klMPORTANT

FIELD

Right Side Piping

(Alternate)

ELECTROSTATIC DISCHARGE (ESD)

Precautions and Procedures

ACAUTION

The unit is equipped with a field make-up box. The make-
up box may be moved to the right side of the furnace to fa-

cilitate installation, If the make-up box is moved to the right
side, the excess wire must be pulled into the blower
compartment. Secure the excess wire to the existing harn-
ess to protect it from damage,

INTERIOR MAKE-UP BOX INSTALLATION

SHUT-OFF VALVE

WILLNOTHOLD

NORMALTEST

PRESSURE |

MANUAL MAIN

CAP

ISOLATE

GAS VALVE

FIGURE 20

\

FURNACE

MAKE-UP

BOX

Right Side

FIGURE 21

Page 21

INTERIORMAKE-UP BOX INSTALLATION

MAKE-UP

Left side / BOX

_ °

FIGURE 22

Refer to figure 24 for field wiring and figure 26 for schematic
wiring diagram and troubleshooting.

1 - Select circuit protection and wire size according to the

unit nameplate. The power supply wiring must meet
Class I restrictions,

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

tate wiring,

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

ther fuse or circuit breaker) near the furnace so that
power can be turned off for servicing,

4 - Before connecting the thermostat or the power wiring,

check to make sure the wires will be long enough for
servicing at a later date, Remove the blower access

panel to check the length of the wire,

5- Complete the wiring connections to the equipment.

Use the provided unit wiring diagram and the field wir-
ing diagram shown in figure 24, Use 18-gauge wire or
larger that is suitable for Class II rating for thermostat

connections,

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

in the absence of local codes, according to the current
National Electric Code (ANSI/NFPA No, 70) for the
USA and current Canadian Electric Code part 1 (CSA
standard C22.1) for Canada. A green ground wire is
provided in the field make-up box,

NOTE - The G4OUH(X) furnace contains electronic
components that are polarity sensitive. Make sure
that the furnace is wired correctly and is properly
grounded.

7 - One line voltage "EAC" accessory terminal is provided

on the furnace control board. Any electronic air cleaner
rated up to one amp can be connected to this terminal

with the neutral leg of the circuit being connected to the
any of the "NEUTRAL" terminals, See figure 25 for con-

trol board configuration, This terminal is energized
whenever the blower is operating,

8 - One line voltage "HUM" accessory terminal is provided

on the furnace control board. Any humidifier rated up
to one amp can be connected to this terminal with the

neutral leg of the circuit being connected to any of the
"NEUTRAL" terminals. See figure 25 for control board
configuration. This terminal is energized in the heating

mode whenever the combustion air inducer is operat-
ing.

9 - Install the room thermostat according to the instruc-

tions provided with the thermostat, See figure 23 for
thermostat designations. If the furnace is being
matched with a heat pump, refer to the FM21 installa-

tion instruction,

G40UH(X) and CONDENSING UNIT

THERMOSTAT DESIGNATIONS

(Refer to specific thermostat and outdoor unit.)

Thermostat G40UH(X)

Furnace

F

Condensing

Unit

POWER

®t .EAT @1

COOMNG@1------

[_3 CONDENSING

UNIT

_t ,NDOOROLOWE

[_\ CONDENSING

UNIT COMMON

COMMON

FIGURE 23

Indoor Blower Speeds

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

blower will run continuously on the heating speed
when there is no cooling or heating demand,

2 - When the G40UH(X)is running in the heating mode,

the indoor blower will run on the heating speed.

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

run on the cooling speed,

Page 22

TYPICAL G40UH(X) FIELD WIRING DIAGRAM

SECONDARY

LIMITS USED

H _LGtr_RSPEED SELECTION, _O

_PEED RI anK YELLOW RED

rAPS IBLACK BROWN YELLOW REO

THERMOSTATHEAT ANTICIPATION SETTINGS

NOTE-

IF ANY WIRE IN THIS APPLIANCE IS REPLACED,IT

MUST BE REPLACED WITH WIRE OF LIKE SIZE
RATIND,INSULAT ON THICKNESS AND TERMINATION,

Z_ IMPORTANT-

TO PREVENT MOTORBURNOUT,NEVER CONNECTMORE
THAN ONE MOTOR LEAD TO ANY ONE CONNECTION.

/_ PARK TERMINALS ARE UNPOWEREDTERMINALS. ALL

UNUSEDMOTOR LEADS MUST BE WIRED TO A
PARK TERMINAL.

Z_ FOR CORRECT NUMBEROF SECTARY

LIMITS USED,SEE SECONDARYLIMIT
SECTION OF BLOWERSPEED CHART.

DAOUH*36B-090 AND
G40UH-ABC-135 0NLY.D0 NOT USE

RED (LOW SPEED) MOTORLEA0
FOR HEATING,LEAVE 0H PARK.

FIELD SUPPLIED ACC. WIRE.

•_ USE COPPER CONDUCTORSONLY,

WARNING-
ELECTRIC SHOCK HAZARD,CAN CAUSE INJURY

OR DEATH.UNIT MUST BE GROUNDEDIN ACCORDANCE
WITH NATIONAL AND LOCAL CODES.

N/A

2

Z

2

FlRIGHT)

2

2

]20V ACC

OR

K43 ECON

(IF USEO)

.... CLASS II VOLTADE FIELD WIRING

LINE VOLTAGE FIELD INSTALLED

DENOTES OPTIONAL COMPONENTS

ROOMTHERMOSTAT

LI LIL__

PRIMARYGAS COMBIFJTI_ AIR

SIO @ $18

LIMIT PROVINGSWITCH

AIR INDUCER

(kJ-TE_ATE)

_ew Gwi_v

Y_HITE-ROD_RE HONEY_dELL

_x

,® - b

s, OlqO OOO

JFLAMEROLLOUT _ IGNITER_J $47

SWITCH __ FLAME JI59 _ FLAMEROLLOUT

S51

S]

6AS VALVE GAS VAt,_,_

SENSOR PIG9 _ SWITCH

TI

N

9®®1 FFt

F_'A--1FI BLOWER

7J j

.--' . i_#o_ _,sLIM,

. _ J

IGNITION/ ,H55

OO

BLOWER OFF

DELAY JUMPER

/

FIGURE 24

INTEGRATED CONTROL BOARD

(Automatic Hot Surface Ignition System)

HUM
LINE

XFMR
EAC
COOL

HEAT
PARK

FLAME
NEUTRALS

"''- 3 AMP, 32 VAC FUSE

TER_HNAL DESIGNATIONS

Humidifier (120VAC)
Input (120VAC)

Transformer (120VAC)

Electronic Air Cleaner (120VAC)
Blower - Cooling Speed (120VAC)
Blower- Heating Speed (120VAC)

Dead terminals to park alternate spd taps
Flame senser

Neutral terminals (120VAC)

W ¢ R ¢; Y

FIGURE 25

Page 23

G4OUH(X) Schematic Wiring Diagram

_20V AOC

OR

K43 ECON

(IF USED)

N

LI

SlO

PRIMARY SAS

LIMIT

0

_, ._ GVI

---- WHITE-ROODERSGAS VALVE

Qlq 0 0

FLAME ROLLOUT __

SWITCH FLAME

AIR INDUCER
COMBUSTION @

BURNERS

SENSOR

COMBUSTION AIR

SI8

PROVINS SWITCH

(ALTERNATE)

OMV

SVL Ouv@

HONEYWELL
GAS VALVE

oo$

IGNITERJR_3_ S€7

JI59 _F_ FLAME ROLLOUT

PISS SWITCH

TI

TRANSFORMER

UNIT I _ HEAT i PARK PARK

24A-0€5 RED )YELLOW .... 3 N/A

36A-070 RED )YELLOW BROWN A 2
36B-090 BROWN 'ELLOW RED 4 I(RISHT)

36C-110 BROWN RED YELLOg 4 I(RISHT)
4BB-070 RED YELLOg BROWN 4 2

€8B-090 YELLOW RED BRDWN A 2

_BLACK BROWN RED YELLOW € I(RIGHT)

€8C-135 BROWN RED YELLOW € 2

6OC-IIO YELLOW RED BROWN 4 I(RIGHT)
60D-135 RED 'ELLOW BROWN 4 2

60D-155 YELLOW RED BROWN 4 2

SPEEDIB ACK YELLOW RED 3

TAPS IBLACK BROWN YELLOW RED 4

ss_ @@@

DOUR ® 0 011_

INTERLOCK

SI

ROOM THERMOSTAT

o_--®®

'till

--= _ _,T'-I -I

:--" -- I DL_"O%ToR

OUTDOOR J _ S¢OUH-36B-090 AND

UNIT _ _j _ G40UH-48C-135 ONLY.DO NOT USE

_Fjr _ .... i{ ) { )1 _ RED (LOW SPEED) MOTOR LEAD ( I rL_ _L I LFAN_

BLACK $51 r -- ] i m

-- LINE VOLTADE FIELD INSTALLED ,_ FIELD SUPPLIED ACC. WIRE.

.... -- CLASSIIVOLTASEFIELOWIRINSDENOTESOPTIONAL COMPONENTS _ USE COPPER CONDUCTORS ONLY. i ?>

-- ( .A92

PSD®®0

®001 _'SS

F3"AJJlF_

1@@(9@(_1

I I'tl I I|

" =11 I

,2

BLOWER
CONTROL

F_ IF ANY WIRE IN THIS APPLIANCE IS REPLACED.IT

P135 MUST BE REPLACED WITH WIRE OF LIKE SIZE.
J135 RATINS.INSULATION THICKNESS AND TERMINATION.

SECONDARY UNUSED MOTOR LEADS MUST BE WIRED TO A
GAS LIMIT PARK TERMINAL.

C€

CAPACITOR SECTION OF BLO@ER SPEED CHART.

L_ FOR HEATINS.LEAVE ON PARE. II

rA92 FusE ..... _ -- T--r_T--_ I

NOTE-

TO PREVENT MOTOR BURNOUT.NEVER CONNECT MORE
THAN ONE MOTOR LEAD TO ANY ONE CONNECTION.

/_ IMPORTANT-

,_ PARK TERMINALS ARE UNDOWERED TERMINALS. ALLS21

,/_ FOR CORRECT NUMBER OF SECONDARY ROOM THERMOSTAT

LIMITS USED.SEE SECONDARY LIUITf_____,[__]

BLOWER SPEED CHART /_k

[FACTORY CONNECTED SPEED TAPS MOTOR

I

YELLOW RED .... 3 2

RED iYELLOW BROWN 4 Z

H_BLO_ER SPEED SELECTION_ 0

THERMOSTAT HEAT ANTICIPATION SETTINGS

_HONEYWELL VALVE ]

1.50 AMPIWHITE-NDDSERS VALVE I

IJ.P58 1JACK/PLUS-BURNER CONTROL

J.PB¢ A K/ U _ AAR N R

IJ.PI56 IJACK/PLUG*INDUCFR/IGNITER
IJ.PI59 IJACK/PLUG-IGNITION

JACKPLUS CHART

SPEEDS

AVAIL. LIMITS USED

SECONDARY

SI

EQUIPMENT _ ==

OROoNDI _ I_; I I'_

_ I I _ lO.-o..;-r .Jl I l

PI56 c_

_- _L_ SEEDLD_R_[

SPEEDCHART

"V PI56 X_ J_ \_B ] (

120V BLOWER

NEUTRAL ._1 _TOii ;

N --

WARNING-
ELECTRIC SHOCK HAZARD,CAN CAUSE INJURY

OR DEATH.UNIT MUST BE GROUNDED IN ACCORDANCE

WITH NATIONAL AND LOCAL CODES.

P58 _ = _

FIGURE 26

Page 24

FOR YOUR SAFETY READ BEFORE LIGHTING

-&WARNING

-&WARNING

-&CAUTION

3 - Turn off all electrical power to the unit,
4 - This furnace is equipped with an ignition device which

automatically lights the burners, Do not try to light the

burners by hand,
5 - Remove the upper access panel,
6 - Honeywell VR8205 Gas Valve with QN/QFF Switch

- Move gas valve switch to OFF, See figure 27.
Honeywell VR8205 Gas Valve with Control Knob -

Turn knob on gas valve clockwise _ to OFF, Do not
force, See figure 28.

White Rodgers 36G Gas Valve - Move gas valve

switch to OFF. See figure 29,

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

gas, STOP! Immediately call your gas supplier from a
neighbor's phone. Follow the gas supplier's instruc-
tions. If you do not smell gas go to next step.

Honeywell VR8205 Series Gas Valve

MANIFOLD (With On/Off Switch)

PRESSURE

MANIFOLD

SCREW PRESSURE

(under cap) OUTLET

BEFORE LIGHTING smell all around the appliance area for

gas, Be sure to smell next to the floor because some gas is
heavier than air and will settle on the floor.

The gas valve on the G40UH(X) unit may be equipped with
either a gas control knob or gas control lever. Use only your

hand to push the lever or to turn the gas control knob. Never
use tools. Ifthe knob will not turn or if the lever will not move

by hand, do not try to repair it. Call a qualified service tech-
nician, Force or attempted repair may result in a fire or ex-

plosion.
Placing the furnace into operation:
G40UH(X) units are equipped with an automatic hot sur-

face ignition system. Do not attempt to manually light

burners on these furnaces. Each time the thermostat calls

for heat, the burners will automatically light, The igniter

does not get hot when there is no call for heat on units with
this ignition system.

a,WARNING

Gas Valve Operation (Figures 27, 28 and 29)

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

this section,

2 - Set the thermostat to the lowest setting,

GAS VALVE ON/OFF SWITCH SHOWN IN OFF POSITION

FIGURE 27

Honeywell VR8205 Series Gas Valve

with Gas Control Knob

MANIFOLD MANIFOLD

PRESSURE . _V _ PRESSURE

ADJUSTMENT"_&___4" I h "--_"1, OUTLET

SCREW _

GAS VALVE SHOWN IN OFF POSITION

FIGURE 28

White Rodgers 36G Series Gas Valve

MANIFOLD

PRESSURE

ADJUSTMENT

SCREW

(Undercover

SCOW)

PRESSURE

POST

GAS VALVE SHOWN IN OFF POSITION

FIGURE 29

Page 25

8- Honeywell VR8205 Gas Valve with ON/OFF Switch

- Move gas valve switch to ON. See figure 27.
Honeywell VR8205 Gas Valve with Control Knob -

Turn knob on gas valve counterclockwise _ to ON,
Do not force. See figure 28,

White Rodgers 36G Gas Valve - Move gas valve

switch to ON, See figure 29,

9 - Replace the upper access panel,
10- Turn on all electrical power to to the unit,
11- Set the thermostat to desired setting,

NOTE - When unit is initially started, steps 1 through 11
may need to be repeated to purge air from gas line,

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

"Turning Off Gas to Unit" and call your service techni-
cian or gas supplier,

Turning Off Gas to Unit

1 - Set the thermostat to the lowest setting,

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

performed,

3 - Remove the upper access panel,

4 - Honeywell VR8205 Gas Valve with ON/OFF Switch

- Move gas valve switch to OFF, See figure 27.
Honeywell VR8205 Gas Valve with Control Knob -

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

force, See figure 28.

White Rodgers 36G Gas Valve - Move gas valve

switch to OFF. See figure 29,

5 - Replace the upper access panel,

Heating Sequence Of Operation

1 - When thermostat calls for heat, combustion air inducer

starts.

2 - Combustion air pressure switch proves blower opera-

tion, Switch is factory set and requires no adjustment,

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

ergizes,

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

valve solenoid opens.

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

combustion process continues,

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

tion control will repeat steps 3 and 4 four more times
before locking out the gas valve ("WATCHGUARD"

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

matically repeat steps 1 through 6 after 60 minutes,

Gas Flow (Approximate)

1 - Operate unit at least 15 minutes before checking gas

flow. Determine the time in seconds for one revolu-
tions of gas through the meter. A portable LP gas me-

ter (17Y44) is available for LP applications,

2 - Compare the number of seconds and the gas meter

size in table 10 to determine the gas flow rate. Multiply
the gas flow rate by the heating value to determine the
unit input rate, If manifold pressure is correct and the
unit input rate is incorrect, check gas orifices for proper

size and restriction,

3 - Remove temporary gas meter if installed,

NOTE - To obtain accurate reading, shut off all other gas
appliances connected to meter,

TABLE 10

Gas Flow Rate (Ft._/Hr.)

Seconds for 1

Revolution

10
12

14
16

18

2O
22
24

26
28

3O
32

34
36

38

4O
42
44

46
48

5O
52

54
56

58

6O

1/2 cu ft Dial 1 cu ft Dial

Gas Meter Size

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

AIMPORTANT

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

move thermostat from "Heat" to "OFF" then back to
"Heat", Heating sequence then restarts at step 1.

Page 26

Gas Pressure

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

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

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

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

justed, check the manifold pressure. A natural gas to

LP/propane gas changeover kit is required to convert
the unit, Manifold pressure for all units is given in table
NO TAG. See figures 27, 28 and 29 for the location of

the manifold pressure adjustment screws,

NOTE - In Canada, certification for installations at eleva-
tions over 4500 feet (1372 m) is the jurisdiction of local au-

thorities,

Manifold pressure for all units fueled by natural gas at all
altitudes is 3,5" w,c. Manifold pressure for all units fueled
by L,P./propane gas at all altitudes is 10,0" w,c,

NOTE - A natural to L.R propane gas changeover kit is nec-
essary to convert this unit. L.P. conversion kit 25W20 is
used with all units installed at altitudes up to 7,500 feet. L.P.

conversion kit 25W21 is used with all units installed at alti-
tudes from 7,501 to 10,000 feet above sea level, Refer to
the changeover kit installation instruction for the conver-

sion procedure.
NOTE - Units fueled by natural gas and installed at alti-
tudes of 7501-10,000 feet above sea level require instal-
lation of a high altitude orifice kit (59Mr 7).

The combustion air pressure switches are factory-set and
require no adjustment. The existing unit pressure switch
must be replaced by pressure switch 56L32 for G40UH(X)

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

Primary and Secondary Limits

The primary limit is located on the heating compartment
vestibule panel. The secondary limits (if equipped) are lo-
cated in the blower compartment, attached to the back side
of the blower. These limits are factory set and require no
adjustment,

Flame Rollout Switches (Two)
These manually reset switches are located on (or inside of)

the burner box. If tripped, check for adequate combustion
air before resetting,

Pressure Switch
The pressure switch is located in the heating compartment

adjacent to the combustion air inducer. This switch checks

for proper combustion air inducer operation before allow-

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

Temperature Rise
Place the unit into operation with a heating demand, After
supply and return air temperatures have stabilized, check

the temperature rise. If necessary, adjust the blower speed
to maintain the temperature rise within the range shown on
the unit nameplate, Increase the blower speed to decrease
the temperature rise. Decrease the blower speed to in-
crease the temperature rise, Failure to adjust the tempera-
ture rise may cause erratic limit operation,

Fan Control
There is no cooling mode fan on delay; however, there is a

cooling fan off delay of 45 seconds, This delay is not adjust-
able,

The heating mode fan on delay of 45 seconds is not adjust-
able. The heating mode fan off delay (amount of time that
the blower operates after the heat demand has been satis-
fied) may be adjusted by changing the jumper position
across the five pins on the integrated control. The unit is
shipped with a factory fan off setting of 90 seconds. The fan
off delay affects comfort and is adjustable to satisfy individ-
ual applications. Adjust the fan off delay to achieve a supply
air temperature between 90 ° and 110°F at the exact mo-
ment that the blower is de-energized. Longer off delay set-
tings provide lower return air temperatures; shorter set-
tings provide higher return air temperatures, See figure 30,

FAN-OFF TIME ADJUSTMENT

To adjust fan-off timing, reposition jumper across pins to

achieve desired setting,

FIGURE 30

Thermostat Heat Anticipation

Set the heat anticipator setting (if adjustable) according to
the amp draw listed on the wiring diagram that is attached

to the unit,
Electrical

1 - Check all wiring for loose connections.

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

operating).

3 - Check amp-draw on the blower motor.

Motor Nameplate Actual

NOTE - Do not secure the electrical conduit directly to the
air ducts or structure.

Blower Speeds

NOTE - CFM readings are taken external to unit with a dry
evaporator coil and without accessories.

1 - Turn off electrical power to furnace,
2 - Remove blower access panel.
3 - Disconnect existing speed tap at control board speed

terminal,

Page 27

NO TE - Termination ofany unused motor leads must be insu-
lated.

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

gram for desired heating or cooling speed.

5- Connect selected speed tap at control board speed

terminal.

6 - Resecure blower access panel.

7 - Turn on electrical power to furnace,

Electronic Ignition
The integrated ignition control has an added feature of an

internal Watchguard control, The feature serves as an auto-
matic reset device for ignition control lockout because the
burner has failed to ignite, This type of lockout is usually due
to low gas line pressure, After one hour of continuous ther-
mostat demand for heat, the Watchguard will break and re-
make thermostat demand to the furnace and automatically
reset the control to begin the ignition sequence,

Flue And Chimney

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

ness and to make sure there is no blockage,

2 - Check unit for proper draft,

3 - Is pressure switch closed? Obstructed flue will cause

unit to shut off at pressure switch, Check flue and outlet

for blockages.

4- 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.

&,CAUTION

At the beginning of each heating season, a qualified techni-
cian should check the system as follows:

Blower

Check the blower wheel for debris and clean if necessary.
The blower motors are prelubricated for extended bearing

life, No further lubrication is needed,

,&WARNING

Filters

All G40UH(X) filters are installed external to the unit. Fil-
ters should be inspected monthly, Clean or replace the fil-
ters when necessary to ensure proper furnace operation.

Replacement filters must be rated for high velocity airflow.

Table 1 lists recommended filter sizes,

Flue And Chimney

Check the flue pipe, chimney and all connections for tight-
ness and to make sure there is no blockage.

Electrical
1 - Check all wiring for loose connections,

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

operating),

3 - Check amp-draw on the blower motor.

Motor Nameplate Actual

Cleaning the Heat Exchanger and Burners

NOTE - Use papers or protective covering in front of the fur-
nace while you clean furnace,

Cleaning the heat exchanger requires a steel spring
"snake," a reversible drill and a vacuum cleaner, The steel

spring snake may be constructed by purchasing a 4 ft, long
by 1/4 inch diameter steel wire cable and a 1/4 inch diame-

ter wire brush, These items are available at a hardware
store. Insert wire end of brush into the open end of the

spring cable. Crimp the cable around the brush so that the
brush is secured and will not come off during cleaning. At-

tach the other end of the cable to the reversible drill to com-
plete the tool for cleaning the heat exchanger.

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

nace.

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

pressure switch wires, then disconnect them.

3 - Remove the four screws that secure the combustion air

inducer, Carefully remove the combustion air inducer to
avoid damaging blower gasket. If gasket is damaged, it
must be replaced to prevent leakage, See figure 31,

Page 28

G40UH(X) BURNER & HEAT

EXCHANGER REMOVAL

HEAT

BURNER BOX ASSEMBLY

FIGURE 31

4 - Remove the collector box located behind the combus-

tion air inducer. Be careful with the collector box gas-
ket. If the gasket is damaged you must replace it to pre-

vent leakage.

5 - Label the wires from gas valve and rollout switches,

then disconnect them.

6 - Disconnect gas supply piping. Remove four screws se-

curing the burner manifold assembly to the vestibule
panel and remove the assembly from the unit.

NOx INSERTS

(X models only)

operate the drill on slow speed. Move the cable in and
out of the heat exchanger section three or four times or

until sufficient cleaning is accomplished. Reverse drill
and slowly work the cable out of opening.

9- Repeat procedure for each heat exchanger section.

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

cleaned, insert the brush end of the cable snake into
the bottom openings of each of the heat exchanger

sections. Clean the bottom opening as described in
step 8.

11- Remove cable from heat exchanger. Use a vacuum

cleaner to remove debris knocked loose during clean-
ing from each heat exchanger section.

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

um cleaner to the top d the heat exchanger section.
Any loose debris will be forced to the bottom of the heat
exchanger section. Vacuum debris from bottom open-

ings.

13- Replace collector box and combustion air inducer.

Check gaskets for damage. Damaged gaskets must be
replaced to avoid heat exchanger leaks. Replace all

screws to the collector box and combustion air inducer.

Failure to replace all screws may cause leaks.

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

brush attachment over the face of burners. Visually in-
spect inside the burners and crossovers for any blockage

caused by foreign matter. Remove any blockage.

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

at the entrance to each heat exchanger opening. See
figure 32.

16- Replace burner/manifold assembly onto the vestibule

panel.

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

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

18- Reconnect vent pipe to combustion air inducer outlet.
19- Reconnect gas supply piping.

20- Turn on power and gas supply to unit.
21- Set thermostat and check for proper operation.

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

leaks. Use a leak detecting solution or other preferred
means.

FIGURE 32

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

the NOx insert to the corbel at the entrance to each
heat exchanger section. Carefully remove the NOx in-

sert from each section. See figure 32.

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

of the heat exchanger openings. Do not force the
cable into the heat exchanger. Insert the cable and

ACAUTION

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

repair leak.

24- Repeat steps 23 and 24 until no leaks are detected.
25- Replace front access panel.

Page 29

ThefollowingrepairpartsareavailablethroughLennoxdealers.Whenorderingparts,includethecompletefurnacemodel
numberlistedontheCSAnameplate--Example:G40UH(X)-24A-045-1.

CabinetParts

Upperaccesspanel
Blowerpanel

Topcap

ControlPanelParts

Transformer

Integratedignitioncontrolboard
Doorinterlockswitch

Circuitbreaker

BlowerParts

Blowerwheel
Motor

Motormountingframe

HeatingParts

Flamesensor
Heatexchangerassembly

Gasmanifold
Combustionairinducer

Gasvalve

Mainburnercluster
Mainburnerorifices
Pressureswitch

Igniter
Primarylimitcontrol

Flamerolloutswitch

Secondarylimit(notusedon24A-45-1)

Motorcapacitor
Blowerhousingcutoffplate

DIAGNOSTIC CODES

Make sure to Identify LED'S Correctly.

Refer to figure NO TAGfor control board layout.

LED #1 (Red) LED #2 (Green) DESCRIPTION

SIMULTANEOUS SIMULTANEOUS Power on - Normal operation.

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

SIMULTANEOUS SIMULTANEOUS

FAST FLASH FASTFLASH

Normal operation - signaled when heating demand initiated at thermostat.

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

OFF SLOW FLASH OR: Blocked inlet/exhaust vent;

ALTERNATING ALTERNATING Watchguard -- burners failed to ignite or lost flame 5 times during single heating

SLOW FLASH SLOW FLASH demand.

SLOW FLASH OFF Flame sensed without gas valve energized.

ON SLOW FLASH Rollout switch open. OR: 12-pin connector improperly attached.
ON ON
ON OFF Circuit board failure or control wired incorrectly.

OFF ON

FAST FLASH SLOW FLASH Main power polarity reversed. Switch line and neutral.
SLOW FLASH FAST FLASH Low flame signal. Measures below 1.5 microamps. Replace flame sense rod.
ALTERNATING ALTERNATING Improper main ground.

FAST FLASH FASTFLASH OR: Line voltage below 90 volts.

NOTE - Slow flash rate equals 1 Hz (one flash per second). Fast flash rate equals 3 Hz (three flashes per second).
Minimum flame sense current = O.5 microAmps.

goes into 1 hour Watchguard.
Pressure prove switch open.

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

Page 30

HEATING SEQUENCE OF OPERATION

I

:q

I

[

I
I

I

NORMAL HEATING MODE

I POWER ON ]

CONTROL SELF-CHECK OKAY?

YES !

IS POLARITY CORRECT?

YES !

IS THERE A PROPER GROUND?

YES l

IS VOLTAGE

ABOVE 90 VOLTS?

YES 1

ROLLOUT SWITCH CLOSED?

NO

YESJ

BURNER OFF?

(CONTINUOUS FLAME CHECK)

YES _

NORMAL OPERATION:

LED #1 -- SLOW FLASH
LED #2 -- SLOW FLASH

YES _

THERMOSTAT CALLS FOR HEAT:

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

YES _l

PRIMARY AND SECONDARY LIMIT SWITCH.

PRESSURE SWITCH OPEN?

IS COMBUSTION AIR INDUCER

HAS COMBUSTION AIR PRESSURE

SWITCH CLOSED IN 2.5 MINUTES?

CLOSED?

YES

IS COMBUSTION AIR

YES _

ENERGIZED?

YES _

YES _

GAS VALVE OFR COMBUSTION AIR INDUCER OFF.

iN..___q2_,o

(RESET CONTROL BY TURNING MAIN POWER OFF.)

NO

NO

LEDs SIGNAL FAST ALTERNATING FLASH.

CONTROL WILL NOT RESPOND TO A CALL FOR

.[

HEATING UNTIL VOLTAGE RISES ABOVE 95 VOLTS.

NO

Jl NO II,[

9

GAS VALVE OFF. COMBUSTION AIR INDUCER ON.

SEQUENCE HOLDS UNTIL ROLLOUT SWITCH CLOSES

AND POWER IS RESET OR T'STAT IS INTERRUPTED

GAS VALVE OFR COMBUSTION AIR INDUCER ON.

PRESSURE SWITCH IS IN WATCHGUARD MODE.

GAS VALVE OFF: COMBUSTION AIR INDUCER OFF.

INDOOR BLOWER OFF WITH DELAY,

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

IS 5-MINUTE RESET PERIOD COMPLETE?

ABNORMAL HEATING MODE

INDOOR BLOWER DELAY OFF.

LED #1 ON
LED #2 ON

POLARITY REVERSED,

LED #1 -- FAST FLASH

LED #2 -- SLOW FLASH

IMPROPER GROUND,
LED #1 -- ALTERNATING FAST FLASH
LED #2 -- ALTERNATING FAST FLASH

INDOOR BLOWER ON.

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

FOR MINIMUM OF 1 SECOND,

INDOOR BLOWER ON HEATING SPEED,

LED #1 -- SLOW FLASH

LED #2 -- OFF

COMBUSTION AIR INDUCER OFF.

INDOOR BLOWER ON

LED #1 SLOW FLASH RATE

LED #2 -- ON

GAS VALVE OFF:

COMBUSTION AIR INDUCER OFF.

INDOOR BLOWER OFF WITH DELAY,

LED #1 OFF

LED #2 SLOW FLASH

(Sequence holds until pressure switch

opens or thermostat resets control,)

_ YES

CONTINUED NEXT PAGE

Page 31

HEATING SEQUENCE CONTINUED

NORMAL HEATING MODE ABNORMAL HEATING MODE

15-SECOND COMBUSTION AIR INDUCER PREPURGFI9

INITIATED BY CLOSED PRESSURE SWITCH. I

YES

I IGNITER WARM-UP -- 20 SECONDS. I'_1

4-SECOND TRIAL FOR IGNITION.

GAS VALVE OPENS. IGNITER ENERGIZED FOR

YES

UP TO 4 SECONDS.

NO

IS VOLTAGE ABOVE 90 VOLTS?

YES

LEDS SIGNAL

ALTERNATING

FAST FLASH UNTIL

VOLTAGE IS ABOVE

95 VOLTS, THEN

RESTARTS HEATING

SEQUENCE.

YES

FLAME STABILIZATION PERIOD.

4 SECONDS _

FLAME RECTIFICATION CURRENT

CHECK. CAN FLAME BE PROVEN WITHIN

4 SECONDS AFTER GAS VALVE OPENS?

(0.5 microamps)

YES _

,4

FLAME SIGNAL 1.5 MICROAMPS OR GREATER?

I

I
I

I ROLLOUT SWITCH CLOSED?

_'I COMBUSTION AIR PRESSURE

I THERMOSTAT DEMAND SATISFIED.

I LED #1 & #2 SIMULTANEOUS SLOW FLASHES.

COMB. AIR INDUCER CONTINUES 5-SECOND

POST PURGE AFTER T'STAT DEMAND IS SATISFIED.

INDOOR AIR BLOWER COMPLETES SELECTED

[ OFF DELAY BEFORE SHUTT NG OFF.

FLAME PRESENT?

YES 1

YES _

INDOOR BLOWER ON

AFTER 45-SECOND DELAY

YES _1

PRIMARY AND SECONDARY LIMIT

SWITCHES CLOSED?

YES

YES

SWITCH CLOSED?

YES

YES

YES

HAS CONTROL FAILED TO SENSE FLAME FOR

I HEAT DEMAND?

I__ WATCHGUARD MODE. GAS VALVE OFF. I_

_t HAS CONTROL RESET IGNITION pI NO

F VE CONSECUT VE TR ES DUR NG A S NGLE

GAS VALVE OFF. COMBUSTION AIR INDUCER ON.

LEDs SIGNAL WATCHGUARD FAILURE CODE.

IS 60-MINUTE RESET PERIOD COMPLETE?

INDOOR BLOWER OFF. I NO

_t ES

COMBUSTION AIR INDUCER OFF.

INDOOR BLOWER OFF WITH DELAY

SEQUENCE FOUR TIMES?

YES

I

(Does not affect operation of control) MODE. GAS VALVE, COMB. AIR

LOW FLAME SIGNAL LIMIT SWITCH WATCHGUARD

LED #1 -- SLOW FLASH INDUCER AND INDOOR BLOW-

LED #2 -- FAST FLASH

I GAS VALVE DE-ENERGIZED. INTERRUPTED OR

I COMBUSTION AIR INDUCER DE-ENERGIZED. I T'STAT IS CYCLED

I NO I INDOOR BLOWER ON UNTIL SWITCH CLOSES. I OFF/ON FOR 1

I I IS LIMIT SWITCH CLOSED? I 60-MINUTE WATCH-

__'_NI_.._, THERMOSTAT IS CYCLED OFF/ON FOR 1 SEC. MINIMUM.

LED #1 -- SLOW FLASH. LED #2 -- ON. I SEC. MINIMUM.

I HAS PRIMARY / SECONDARY IYES LIMIT CLOSES.

NO GAS VALVE POWER OFF.

LIMIT RESET TIME _ IS 60-MIN PERIOD

EXCEEDED 3 MINUTES? COMPLETE?

COMBUSTION AIR INDUCER POWER ON.

SEQUENCE HOLDS UNTIL ROLLOUT SWITCH IS RESET

AND MAIN POWER IS INTERRUPTED OR

INDOOR BLOWER ON

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

I i

GAS VALVE DE-ENERGIZED.

I INDOOR BLOWER OFF WITH DELAY

I I HASCABSWITCHCLOSEDIN2.5MINUTES?I

I

COMBUSTION AIR INDUCER ON. YES

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

NO

I 5"M'NUTEPRESSURESW'TCHI

WATCHGUARD MODE.

ER OFF. LEDs SIGNAL LIMIT
SWITCH OPEN UNTIL MAIN

POWER IS

GUARD PERIODYES STARTS AT TIME

• I NO

b

Page 32

COOLING SEQUENCE OF OPERATION

NORMALCOOLING MODE

I POWER ON I

IGNITION CONTROL MAIN POWER ON.

I

I

CONTROL SELF DIAGNOSTIC CHECK.

IS CONTROL OPERATING NORMALLY?

YES _l

IS THERE A PROPER GROUND?

YES _

IS POLARITY CORRECT?

YES _

I ISVOLTAGE I

ABOVE 90 VOLTS?

NO

CONTROL WILL CONTINUE TO CALL FOR COOLING

_ IGNAL POLARITY REVERSED AT LED. CONTROL I

NO

WILL CONTINUE TO CALL FOR COOLING IN THIS

"1

ABNORMALCOOLING MODE

GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.

INDOOR BLOWER OFF WITH NORMAL DELAY.

SIGNAL CIRCUIT BOARD FAILURE AT LED.

INTERRUPT MAIN POWER TO RESET CONTROL,

SIGNAL IMPROPER GROUND AT LED.

IN THIS CONDITION,

CONDITION,

LED SIGNALS LOW VOLTAGE. CONTROL WILL

CONTINUE TO CALL FOR COOLING

IN THIS CONDITION,

/

YES[ I GAS VALVE OFF. COMBUSTION AIR INDUCER ON.

T

ROLLOUT SWITCH MONITORED CONTINUOUSLY. _ SIGNAL ROLL-OUT SWITCH OPEN AT LED.

I

IS ROLLOUT SWITCH CLOSED? I_1 SEQUENCE HOLDS UNTIL ROLLOUT SWITCH CLOSES

YES / IS CYCLED OFF/ON FOR 1 SEC. MINIMUM.

J /AND MAIN POWER IS INTERRUPTED OR THERMOSTAT

, NO LI INDOOR BLOWER ON.

LED: SLOW FLASH RATE REMAINS UNCHANGED I

I

I

I

I

I

[

THROUGHOUT COOLING CYCLE.

THERMOSTAT CALLS FOR COOLING. I

COMPRESSOR CONTACTOR AND SYSTEM FAN I

ENERGIZED WITH 2-SECOND DELAY

(COOLING SPEED), EAC TERM, ENERGIZED,

THERMOSTAT OPENS. I

COMPRESSOR OFF. I

SYSTEM FAN AND EAC TERM. OFF |

WITH 45-SECOND DELAY.

I

I

J

Page 33

CONTINUOUS HEAT SPEED FAN SEQUENCE OF OPERATION

I

LED: SLOW FLASH RATE REMAINS

UNCHANGED THROUGHOUT SEQUENCE.

MANUAL FAN SELECTION MADE AT THERMOSTAT.

CONTROL (G) ENERGIZES SYSTEM FAN AT HEAT

SPEED. EAC TERMINAL IS ENERGIZED.

THERMOSTAT CALLS FOR HEAT (W).

NO

I THERMOSTAT CALLS FOR COOLING.

YES NO

I SYSTEM FAN SWITCHED TO COOL SPEED. I

I THERMOSTATOPENS. I

Job Name Job No.
Job Location City

Installer City
Unit Model No. Technician

Serial No.

Electrical Connections Tight? []
Blower Motor Amps

Fuel Type: Natural Gas? []
Furnace Btu Input

Regulator Pressure __ w.c. - Nat.:
Flue Connections Tight? []
Combustion Gas Tested? CO2 []

Fan Control Setting (45 Seconds Fixed On)
Fan Control Off Setting
Filter Clean & Secure? []

Calibrated? []

EAC TERM, REMAINS ON.

/
[I MANUAL FAN SELECTION MADE AT THERMO'STAT

11_11_ CONTROL (G) ENERGIZES SYSTEM FAN AT HEAT I I

I SPEED. EAC TERM. ENERGIZED.

Heating Section

Supply Voltage Blower Motor H.P.

Gas Piping Connections Tight & Leak-Tested? []

LP/Propane Gas? []

w.c. - LP/Propane

CO []

Vent Clear? []

Thermostat

Heat Anticipator Properly Set? []

I

HUM TERM. ENERGIZES

WITH COMB. AIR INDUCER.

YES

SYSTEM FAN REMAINS ON

HEATING SPEED.

THERMOSTAT OPENS.

HUM TERM. DE-ENERGIZES

WITH COMB. AIR INDUCER

SYSTEM FAN REMAINS ON

HEATING SPEED. 1

Date

State
State

Line Pressure

Proper Draft? []

Temperature Rise

Level? []

Page 34