Napoleon NBM030S2A User manual

IOM
W415-1117 / A / 03.11.14
UM
PG
57
$10.00
INSTALLER: PLEASE FAMILIARIZE YOURSELF WITH VENTING/DRAINING SECTIONS OF
THIS MANUAL BEFORE PROCEEDING WITH THE INSTALLATION. LEAVE
THIS MANUAL WITH THE APPLIANCE FOR FUTURE REFERENCE.
CONSUMER: RETAIN THIS MANUAL FOR FUTURE REFERENCE.
INSTALLATION AND
OPERATING INSTRUCTIONS
Wolf Steel Ltd., 24 Napoleon Rd., Barrie, ON, L4M 0G8 Canada /
103 Miller Drive, Crittenden, Kentucky, USA, 41030
Phone [phone] • Fax [phone] • www.napoleonheatingandcooling.com • [email protected]
SAFETY INFORMATION
ELECTRICAL SHOCK, FIRE OR
EXPLOSION HAZARD
Failure to follow safety warnings exactly
could result in serious injury, death or
property damage.
Improper servicing could result in
dangerous operation, serious injury, death
or property damage.
- Installation and service must be performed by a
qualified installer, service agency or the gas supplier.
- Before servicing, disconnect all electrical power to
furnace.
- When servicing controls, label all wires prior to
disconnecting. Reconnect wires correctly.
- Verify proper operation after servicing.
- Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
- WHAT TO DO IF YOU SMELL GAS:
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use
any phone in your building.
• Leave the building immediately.
• Immediately call your gas supplier from a
neighbour’s phone. Follow the gas supplier’s
instructions.
• If you cannot reach your gas supplier, call the fire
department.
!WARNING !
MANUFACTURER RESERVES THE RIGHT TO DISCONTINUE, OR CHANGE
AT ANY TIME, SPECIFICATIONS OR DESIGNS WITHOUT NOTICE AND
WITHOUT INCURRING OBLIGATIONS.
H1.11
CERTIFIED TO ANSI Z21.47b / CSA 2.3b-2008
9200 SERIES
SINGLE STAGE MULTI POSITION HIGH EFFICIENCY
(CONDENSING) FORCED AIR GAS FURNACE

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TABLE OF CONTENTS
1.0 INTRODUCTION 3
2.0 SAFETY SYMBOLS AND WARNINGS 4
2.1 SAFETY RULES 5
2.2 CODES 6
3.0 FURNACE SIZING 9
4.0 LOCATION OF UNIT 10
4.1 GENERAL GUIDELINES 10
4.2 OTHER CONSIDERATIONS 10
4.3 INSTALLATION IN UPFLOW OR HORIZONTAL POSITIONS 11
4.4 AIR CONDITIONING 12
5.0 COMBUSTIBLE CLEARANCES 12
6.0 DUCTWORK 13
6.1 DUCTWORK STEPS 14
7.0 VENTING AND COMBUSTION PIPING 15
7.1 ACCEPTABLE MATERIALS IN CANADA 15
7.2 ACCEPTABLE MATERIALS IN UNITED STATES 15
7.3 VENT DRAIN OPTION 16
8.0 NON-DIRECT VENT FURNACE INSTALLATIONS USING INDOOR COMBUSTION AIR (ONE PIPE
SYSTEM) 17
8.1 DETERMINING COMBUSTION AIR 18
8.1.1 CASE 1: FURNACE LOCATED IN A UNCONFINED SPACE 18
8.1.2 CASE 2: FURNACE LOCATED IN A CONFINED SPACE 18
8.1.3 CASE 3: FURNACE LOCATED IN A CONFINED SPACE, OUTDOOR AIR FROM ATTIC OR CRAWL SPACE 19
8.1.4 CASE 4: FURNACE LOCATED IN A CONFINED SPACE, OUTDOOR AIR DUCTED HORIZONTALLY 20
8.1.5 CONNECTION TO FURNACE NON-DIRECT VENT 20
9.0 VENTING GUIDELINES 21
9.1 VENT TERMINATION 22
9.2 IN CANADA 23
9.3 IN UNITED STATES 23
9.4 FURNACE VENTING INSTALLATIONS 24
9.4.1 NON-DIRECT VENT INSTALLATION USING INDOOR COMBUSTION AIR (ONE PIPE SYSTEM) 24
9.4.2 DIRECT VENT INSTALLATION USING OUTDOOR COMBUSTION AIR (TWO PIPE SYSTEM) 24
9.4.3 COMBUSTION AIR 24
10.0 TERMINATIONS 25
10.1 COMBUSTION AIR 25
10.2 EXHAUST 25
10.3 CONCENTRIC VENTING KIT 25
10.4 CONCENTRIC VENT TERMINATION INSTALLATION INSTRUCTIONS 25
10.5 LOCATION 25
10.6 MULTIPLE VENTING 26
11.0 ROUTING OPTIONS 29
11.1 EXHAUSTER ROTATION INSTRUCTIONS & PRESSURE SWITCH MOUNTING 29
11.2 CONDENSATE DRAINS 30
11.3 PREPARATIONS FOR VENT AND DRAINING OPTION 30
11 .4 DRAIN HOSE INSTALLATION 33
11.4.1 DRAIN TUBING 33
11.4.2 PRIMING CONDENSATE TRAP 34
11.5 ALTERNATE CONDENSATE DRAIN INSTALLATION USING 1/2” PVC OR 3/4” CPVC 34
11.6 CONDENSATE NEUTRALIZERS 35
12.0 GAS SUPPLY AND PIPING 36
12.1 GAS SUPPLY 36
12.2 GAS PIPING 36
12.3 GAS INLET PRESSURE 37
12.4 LEAK TESTING 37
12.5 PURGING GAS LINES 37
13.0 CONVERSIONS 38
13.1 HIGH ALTITUDE CONVERSION 38
13.2 NATURAL TO LP GAS CONVERSION 38
13.3 CONVERSION STEPS 38
13.4 CHECKING THE INLET GAS PRESSURE 38
13.5 SETTING THE MANIFOLD GAS PRESSURE 39
13.6 CHECKING FURNACE INPUT 40
14.0 ELECTRICAL SPECIFICATIONS 41
14.1 ELECTRICAL WIRING AND CONNECTIONS 41
14.2 FURNACE CONNECTION 42

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1.0 INTRODUCTION
NOTE: Changes, other than editorial, are denoted by a vertical line in the margin.
15.0 LOW VOLTAGE WIRING 43
15.1 THERMOSTAT LOCATION 43
16.0 OPTIONAL ACCESSORIES (FIELD SUPPLIED/INSTALLED) 43
16.1 ELECTRIC AIR CLEANER 43
16.2 POWER HUMIDIFIER 43
17.0 INITIAL STARTUP PROCEDURES 44
17.1 TO START THE FURNACE 44
17.2 TO SHUT DOWN THE FURNACE 44
17.3 SEQUENCE OF OPERATION 45
18.0 AIR FLOW 46
18.1 TEMPERATURE RISE CHECK 46
18.2 CALCULATING AIR FLOW 47
18.3 CONTINUOUS FAN OPERATION 47
19.0 MAINTENANCE AND TROUBLESHOOTING 48
19.1 AIR FILTER 48
19.2 LUBRICATION 49
19.3 TROUBLESHOOTING FLOWCHART 50
19.4 DIAGNOSTIC CODES FOR STATUS LED 51
19.5 FAULT CODE HISTORY 51
20.0 WIRE DIAGRAM FOR SINGLE STAGE FURNACE WITH PSC 52
21.0 WARRANTY 53
22.0 SINGLE STAGE REPLACEMENT PARTS LIST 54
23.0 SERVICE HISTORY 56
H1.22
IMPORTANT:
PLEASE READ THIS MANUAL CAREFULLY
AND KEEP IN A SAFE PLACE FOR FUTURE
REFERENCE BY A SERVICE TECHNICIAN.
ATTENTION:
UPFLOW VENTING RIGHT, MUST DRAIN ON
LEFT SIDE.
H4.0.1
This high efficient gas fired single stage condensing furnace is an upflow, horizontal left and right warm air
furnace suitable for residential and light commercial heating applications with inputs from 30,000 to 120,000
Btu/hr.
This high efficient furnace series is CSA certified as a Category IV indirect or direct vent central forced air
furnace. When installed as a direct vent furnace, all combustion air is supplied to the furnace burners through the
air intake system. (See Section 7, “Ventilation and Combustion Piping.”)
All models may be fired by natural or LP gas (propane), and may be field converted from natural gas to LP gas
using Conversion Kit W370-0018.
The furnace is shipped completely assembled except for the condensate drain trap assembly. Please inspect
for damage when the furnace is unpacked.

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2.0 SAFETY SYMBOLS AND WARNINGS
H3.3.1
Understand and pay particular attention to the words DANGER, WARNING, and CAUTION and the following
defined symbols are used throughout this manual to notify the reader of potential hazards of varying risk levels.
DANGER
! !
INDICATES AN IMMINENTLY HAZARDOUS SITUATION WHICH, IF NOT AVOIDED, WILL
RESULT IN DEATH OR SERIOUS INJURY.
INDICATES A POTENTIALLY HAZARDOUS SITUATION WHICH, IF NOT AVOIDED,
COULD RESULT IN DEATH OR SERIOUS INJURY.
WARNING !
!
INDICATES A POTENTIAL HAZARDOUS SITUATION WHICH, IF NOT AVOIDED, MAY
RESULT IN MINOR OR MODERATE INJURY. IT MAY ALSO BE USED TO ALERT
AGAINST UNSAFE PRACTICES.
CAUTION !
!
H6.0
IMPORTANT:
READ THE FOLLOWING INSTRUCTIONS COMPLETELY BEFORE INSTALLING!
H3.3
WARNING !
!
IF THE INFORMATION IN THESE INSTRUCTIONS IS NOT FOLLOWED EXACTLY, A FIRE
OR EXPLOSION MAY RESULT, CAUSING PROPERTY DAMAGE, PERSONAL INJURY OR
LOSS OF LIFE.
FOR YOUR SAFETY
DO NOT STORE OR USE GASOLINE OR OTHER FLAMMABLE VAPORS AND LIQUIDS, OR
OTHER COMBUSTIBLE MATERIALS IN THE VICINITY OF THIS ORANY OTHER APPLIANCE.
WHAT TO DO IF YOU SMELL GAS
• DO NOT TRY TO LIGHT ANYAPPLIANCE.
• DO NOT TOUCH ANY ELECTRICAL SWITCH; DO NOT USE ANY PHONE IN YOUR
BUILDING.
• IMMEDIATELY CALLYOUR GAS SUPPLIER FROM A NEIGHBOR’S PHONE, ORACEL-
LULAR PHONE FROMALOCATION WELLAWAY FROM THE BUILDING. FOLLOW THE
GAS SUPPLIER’S INSTRUCTIONS.
• IF YOU CANNOT REACH YOUR GAS SUPPLIER, CALL THE FIRE DEPARTMENT.
• DO NOT RE-ENTER THE BUILDING UNTIL AUTHORIZED TO DO SO BY THE GAS
SUPPLIER OR THE FIRE DEPARTMENT.
PROPER INSTALLATION, ADJUSTMENT, ALTERATION, SERVICE OR MAINTENANCE CAN
CAUSE INJURY, PROPERTY DAMAGE OR LOSS OF LIFE. REFER TO THIS MANUAL.
INSTALLATION AND SERVICE MUST BE PERFORMED BY A QUALIFIED INSTALLER,
SERVICE AGENCY OR THE GAS SUPPLIER.

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2.1 SAFETY RULES
H3.4
THESE INSTRUCTIONS ARE INTENDED AS AN AID TO QUALIFIED SERVICE
PERSONNEL FOR PROPER INSTALLATION, ADJUSTMENT AND OPERATION OF
THIS FURNACE. READ THESE INSTRUCTIONS THOROUGHLY BEFORE ATTEMPTING
INSTALLATION OR OPERATION. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY
RESULT IN IMPROPER INSTALLATION, ADJUSTMENT, SERVICE OR MAINTENANCE,
POSSIBLY RESULTING IN FIRE, ELECTRICAL SHOCK, CARBON MONOXIDE
POISONING, EXPLOSION, PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
WARNING !
!
H6.1
1. Use this furnace only with type of gas approved for this furnace. Refer to the furnace rating plate.
2. Install this furnace only in dry indoor locations (protected from weather).
3. Provide adequate combustion and ventilation air to the furnace space as specified in Section 7 of this
manual, “Ventilation and Combustion Piping.”
4. Combustion products must be discharged outdoors. Connect this furnace to an approved vent system only,
as specified in Section 7 of this manual, “Venting and Combustion Piping.”
5. Never test for gas leaks with an open flame. Use a commercially available soap solution made specifically
for the detection of leaks to check all connections as specified in Section 12 of this manual, “Gas Supply
and Piping.”
6. Always install furnace to operate within the furnace’s intended temperature-rise range with a duct system,
which has an external static pressure within the allowable range, listed on the furnace rating plate, and as
specified in Sections 3, 6, and 18 of this manual, “Furnace Sizing,” “Ductwork,” and “Airflow.”
7. When a furnace is installed so that the supply ducts carry air circulated by the furnace to areas outside the
space containing the furnace, the return air shall also be handled by duct(s) sealed to the furnace casing and
terminating outside the space containing the furnace. (Furnace for heating the home located in the attached
garage, for example).
8. A gas-fired furnace for installation in a residential garage must be installed so that the burners and ignitor
are no less than 18” (457 mm) above the floor. The furnace must be located, or protected to avoid physical
damage by vehicles. (See safety warning).
9. This furnace may be used for heating of buildings or structures under construction provided that:
• The furnace is permanently installed with all electrical wiring, piping, venting and ducting 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 casing, and terminate outside the
space containing the furnace.
• Return air temperature range between 55°F (13°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 used to clean the circulating air during the construction process must be either replaced or
thoroughly cleaned prior to occupancy.
• The input rate and temperature rise must be set per the furnace rating plate.
• One hundred percent (100%) outdoor air must be provided for combustion air requirements during
construction. This is to minimize the corrosive effects of adhesives, sealers and entrainment of
drywall dust into combustion air, which can cause fouling and plugging of furnace components.
• The furnace heat exchanger, components, duct system, and evaporator coils must be thoroughly
cleaned following final construction clean-up.
• All furnace operating conditions (including ignition, input rate, temperature rise and venting) must be
verified according to these installation instructions.

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2.2 CODES
H6.2
1. This furnace must be installed:
a. In accordance with all local codes, by-laws and regulations by those authorities having jurisdiction.
b. In Canada, this furnace must be installed in accordance with the current CAN/CGA -B149.1 and .2
Natural Gas and Propane, and the National Electric Code (NEC) NFPA 70.
c. In the United States, this furnace must be installed in accordance with the current ANSI Z223.1 (NFPA
54) National Fuel Gas Code.
2. Electrical connections must be made in accordance with:
a. Any applicable local codes, by-laws and regulations.
b. Canada: current edition of CAN/CSA C22.1 and C22.2, Canadian Electrical Code (Part 1 and 2).
c. United States: current edition of ANSI/NFPA 70, National Electrical Code.
Codes and additional information may be obtained from:
Canadian Standards Association American Gas Association
5060 Spectrum Way 400 North Capitol Street, NW, Suite 450
Mississauga, Ontario, L4W 5N6 Washington DC, 20001
Phone: [phone] Phone: [phone]
website: www.csa.ca website: www.aga.org
National Fire Protection Association
1 Batterymarch Park
Quincy, MA, 02169-7471
Phone: [phone]
website: www.nfpa.org
H3.5
DO NOT INSTALL THIS FURNACE IN A MOBILE HOME! THIS FURNACE IS NOT
APPROVED FOR INSTALLATION IN A MOBILE HOME. DOING SO COULD CAUSE FIRE,
PROPERTY DAMAGE, PERSONAL INJURY OR LOSS OF LIFE.
THE FURNACE CONTAINS FOIL COVERED FIBERGLASS INSULATION. INHALATION OF
FIBERGLASS PARTICLES IS ASSOCIATED WITH RESPIRATORY DISEASE INCLUDING
CANCER.
NATURAL GAS AND PROPANE ARE NORMALLY ODORIZED BY THE FUEL SUPPLIER. IN
SOME CASES, THE ODORANT MAY NOT BE PERCEIVABLE. INSTALLATION OF UL AND
ULC RECOGNIZED FUEL GAS DETECTORS INSTALLED IN ACCORDANCE WITH THEIR
MANUFACTURER’S INSTRUCTIONS IS RECOMMENDED AS AN ADDITIONAL MARGIN OF
SAFETY.
THE EXHAUST GASES FROM THIS FURNACE CONTAIN CHEMICALS WHICH ON
SOME OCCASIONS MAY INCLUDE CARBON MONOXIDE. CARBON MONOXIDE IS AN
ODORLESS, TASTELESS, CLEAR COLORLESS GAS WHICH IS HIGHLY TOXIC. EVEN
LOW CONCENTRATIONS ARE SUSPECTED OF CAUSING BIRTH DEFECTS AND OTHER
REPRODUCTIVE HARM.
UL AND ULC RECOGNIZED CO DETECTORS ARE RECOMMENDED FOR ALL BUILDINGS
EQUIPPED WITH FOSSIL FUEL BURNING APPLIANCES. ALL CO DETECTORS SHOULD
BE INSTALLED IN ACCORDANCE WITH THEIR MANUFACTURER’S INSTRUCTIONS AND
APPLICABLE LOCAL BUILDING CODES.
FIRE, EXPLOSION OR CARBON MONOXIDE POISONING HAZARD!
FAILURE TO REPLACE WITH PROPER CONTROL COULD RESULT IN FIRE, EXPLOSION
OR CARBON MONOXIDE POISONING.
REPLACE GAS VALVE ONLY WITH THE SAME MODEL NUMBER OR AS SPECIFIED BY THE
MANUFACTURER.
WARNING !
!

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H3.6
WARNING !
!
WHEN THIS FURNACE IS INSTALLED IN A RESIDENTIAL GARAGE, IT MUST BE
INSTALLED SO THE BURNERS AND IGNITION SOURCE ARE LOCATED NO LESS THAN
18” (457 mm) ABOVE THE FLOOR TO PREVENT THE RISK OF IGNITING FLAMMABLE
VAPORS WHICH MAY BE PRESENT IN THE GARAGE.
THE FURNACE MUST BE LOCATED OR PROTECTED TO AVOID PHYSICAL DAMAGE BY
VEHICLES.
FAILURE TO HEED THESE WARNINGS CAN CAUSE A FIRE OR EXPLOSION, RESULTING
IN PROPERTY DAMAGE, PERSONAL INJURY OR LOSS OF LIFE.
FIGURE 1 - FURNACE DIMENSIONS
SIDE CUTOUT
LOW VOLTAGE IN
HIGH VOLTAGE IN
ALTERNATE VENT OUTLET
LEFT SIDE DRAIN HOLES
UPFLOW DRAIN HOLE
AIR INLET
ALTERNATE AIR IN
STD. GAS SUPPLY
D
E
& RIGHT SIDE
CONDENSATE
DRAIN TRAP w/
1/2" CPVC
DISCHARGE LEFT
2” PVC VENT OUTLET
C
A
F
G
B
ALT. VENT OUTLET
ALT. AIR INLET
FOR SIDE CUTOUTS
ALT. GAS LINE IN
VOLTAGE IN
ALT. UPFLOW DRAIN HOLE
ALT. LOW
VOLTAGE IN
WITNESS MARKS
ALT. HIGH
RIGHT SIDE DRAIN HOLES
SIDE CUTOUT
5.125"
(130mm)
TOP
LEFT SIDE FRONT RIGHT SIDE
TABLE A - FURNACE DIMENSIONS
INPUT OUTPUT Width Depth Height Supply Air Return Air
MODEL Btu/hr Btu/hr A B C (F x G) (D x E)
NBM030S2A 30 000 28 200 14 1/2"
(356mm)
29 1/2"
(737mm)
32 7/8"
(835mm)
13 1/4" X 19 5/8"
(337mm x 499mm)
14" x 23"
(356mm x 584mm)
NBM040S2A 40 000 36 800
NBM040S3A 40 000 36 800 17 1/2"
(445mm)
16 1/4" X 19 5/8"
(413mm x 499mm)
NBM060S2A 60 000 55 200 14 1/2"
(356mm)
13 1/4" X 19 5/8"
(337mm x 499mm)
NBM060S3A 60 000 55 200 17 1/2"
(445mm)
29 1/2"
(737mm)
32 7/8"
(835mm)
16 1/4" X 19 5/8"
(413mm x 499mm)
14" x 23"
(356mm x 584mm)
NBM080S3A 80 000 73 600
NBM080S4A 80 000 73 600 21"
(533mm)
19 3/4" X 19 5/8"
(502mm x 499mm)
NBM100S4A 100 000 92 000
NBM100S5A 100 000 92 000 24 1/2"
(622mm)
23 1/4" X 19 5/8"
(590mm x 499mm)
NBM120S5A 120 000 110 400
H12.6.1

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TABLE B - MINIMUM CLEARANCES TO COMBUSTIBLE
MATERIALS (INCHES)
0"
Top
NOTES:
S - Service clearance 24 inches (610mm) or more.
C - Combustible oor (but not carpet or non-ceramic tile).
All models approved for closet installation.
Plenum
1/2" (13mm)
on all sides
0"
0"
0"
0"
UPFLOW HORIZONTAL
TOP
0
PLENUM TOP
1/2" (13mm)
FRONT
H12.11.1
BACK
SIDES
BOTTOM
FLUE PIPE
ENCLOSURE
CLOSET CLOSET
0
1/2" (13mm)
0* 0*
00
0 0**
0*** 0
00
*24" (610mm) REQUIRED FOR SERVICE
**SUPPLY AIR OUTLET / 1/2" (13mm) RETURN AIR INLET
***CERTIFIED FOR CLOSET INSTALLATION ON COMBUSTIBLE FLOORING.

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3.0 FURNACE SIZING
TABLE 1 - RANGE OF TEMPERATURE RISE
Furnace Models Temperature Rise
NBM030S2A 35 - 65°F (20 - 36°C)
NBM040S2A 35 - 65°F (20 - 36°C)
NBM40S3A 30 - 60°F (17 - 33°C)
NBM060S2A 35 - 65°F (20 - 36°C)
NBM060S3A 35 - 65°F (20 - 36°C)
NBM080S3A 35 - 65°F (20 - 36°C)
NBM080S4A 35 - 65°F (20 - 36°C)
NBM100S4A 30 - 60°F (17 - 33°C)
NBM100S5A 30 - 60°F (17 - 33°C)
NBM120S5A 35 - 65°F (20 - 36°C)
H12.15.1
H7.0.1
NOTE:
The return air system is equally as important as the
supply air system. An under-sized return air system
will prevent sufficient quantities of air from reaching
the supply air system and will consequently reduce the
service life of the furnace and its components.
The maximum hourly heat loss for each heated space shall be calculated in accordance with the procedures
described in the manuals of the Heating, Refrigeration and Air Conditioning Institute of Canada (HRAI), or
by any other method which is suitable for local conditions, provided the results obtained are in substantial
agreement with, and not less than those obtained using the procedure described in their manuals.
In the United States, “Manual J - Load Calculation,” published by the Air Conditioning Contractors of America,
describes a suitable procedure for calculating the maximum hourly heat loss.
If the installation is a retrofit application, do not rely on the capacity of the existing heating equipment as a
method to size the new furnace. Many of the heat transfer multiples listed in earlier versions of load calculation
manuals were much higher than those listed in more recent editions. It is possible that energy saving
measures have been completed since the installation of the existing furnace. This might include additional
insulation in the attic or walls, the application of sprayed foam insulation, the addition of storm windows and
doors, weather-stripping, caulking, etc.
Many of the older furnaces were equipped with large belt drive blower systems, operating at low RPM’s. If
replacing an existing furnace, be sure that the existing ductwork can handle the amount of airflow necessary
for a reasonable temperature rise. Most older gas furnaces operated with a system temperature rise of 70
- 100°F (39 - 56°C). These furnaces are designed to be
operated with a system temperature rise (∆T) of 35 - 65°F
(20 - 36°C) or 30 - 60°F (14 - 31°C) depending on what
model is installed. If the furnace selected has an identical
output capacity as the original furnace, a substantial
increase in system air flow will be necessary. See Table 1
and the airflow characteristics in Section 18 of this manual,
“Airflow”.
Existing ductwork should be assessed for its air handling
capabilities.
The “Equal Friction Chart,” as published by ASHRAE
and HRAI, is the basis for the various air duct calculators
available through heating supply companies. Following
the air velocity guide lines, according to the “Equal Friction
Chart,” or a slide rule air duct calculator, a typical 6”
(152mm) round duct has a capacity of approximately 100
cfm.

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4.0 LOCATION OF UNIT
4.1 GENERAL GUIDELINES
FIGURE 3 - SUGGESTED METHOD FOR SUSPENDING HORIZONTAL FURNACE
RETURN AIR PLENUM
ALLOW ENOUGH ANGLE
IRON OVERHANG TO
PERMIT OPENING THE
BLOWER DOOR.
• 3/8” THREADED ROD
• 2” (51mm) ANGLE IRON
• JAM NUTS
• LOCK WASHER
• FLAT WASHER
SUPPLY AIR PLENUM
4.2 OTHER CONSIDERATIONS
H8.1.1
1. Select a location where the exhaust and combustion air piping can be routed between the furnace and
their terminations with a minimum of lengths and fittings. Be sure to check that the proposed termination
location will meet code requirements with respect to location and minimum clearances. (See venting
section for minimum and maximum limits.)
2. Select a location as near as possible to the existing or proposed duct system.
3. The furnace location must have provisions for condensate drainage. If a suitable drain is unavailable near
the furnace, a condensate pump must be used. The condensate pump drain tubing must not terminate
outdoors; similar to some air conditioning condensate installations. Be sure to select a condensate pump
that has been approved for furnace condensate applications.
4. The furnace location must permit access for servicing and be within the clearance to combustibles
guidelines as marked on the appliance rating plate.
5. The furnace must be installed on a level surface. It is recommended that the rear of the furnace be
elevated 1/4” (6mm) higher than the front to facilitate proper condensate drainage.
6. If the furnace is being installed so that the return air will enter through the bottom, the perimeter of the
furnace must be properly supported.
7. When installed in the horizontal position, the furnace may be supported from the bottom, or suspended.
(Figure 3). Be sure to install a Horizontal Kit. Kit # W370-0027.
8. In upflow right venting configuration, furnace must drain on the left side.
1. If the furnace is to be located in an area where the combustion air is laden with chemical compounds such
as bromine, chlorine or fluorine, as may be found in swimming pool chemicals, laundry detergents, etc.,
use outdoor air for combustion. These compounds when exposed to flame, form acids which attack the
heat exchanger and other components.
Exposure to the following substances in the combustion air supply (but not limited to the following) will also
require OUTDOOR AIR for combustion:
• Aerosols, particularly CFC based or propelled aerosols
• Air fresheners

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4.3 INSTALLATION IN UPFLOW OR HORIZONTAL POSITIONS
H8.2
• “Airplane Glue” and similar adhesives and cements
• Ammonia, as commonly found in permanent wave solutions used in hair dressing salons
• Anti-static fabric softeners used in clothes dryers
• Carbon tetrachloride
• Chlorinated cleaners and waxes
• Chlorine and bromine based swimming pool chemicals
• De-icing salts or chemicals (rock salt, etc.)
• Dry cleaning fluids such as perchloroethylene
• Fumes from curing polyurethane and similar substances
• Halogen based refrigerants including R-12 and R-22
• Hydrochloric acid, muriatic acid and other acid based masonry washing and curing materials
• Printer’s inks, paint removers, varnishes, varsol, toluene, etc.
• Water softener salt and chemicals
2. If this furnace is to be installed in an area over a finished ceiling or living area, install a field fabricated
auxiliary drain pan under the furnace to protect that area from accidental condensate spills. The auxiliary
pan should be large enough to collect accidentally spilled condensate from the air conditioning evaporator
coil assembly if applicable.
3. If the furnace is installed in an area where freezing may occur, a garage, an attic, a crawl space or any
unconditioned space, steps must be taken to protect the condensate trap and drain line from freezing.
H8.3.1
UPFLOW INSTALLATION: Vent positioning, pressure switch location and drain locations shall be performed in
accordance with instructions in the appropriate sections of this manual.
HORIZONTAL INSTALLATION: Vent positioning, pressure switch location and drain locations shall be performed in
accordance with instructions in the appropriate sections of this manual.
NON-SUSPENDED INSTALLATION: Maintain clearances to combustibles as outlined in Table B. The furnace
must be supported in such a way as to not allow twisting or sagging of the cabinet.
SUSPENDED INSTALLATION: Maintain clearances to combustibles as outlined in Table B. The furnace may
be suspended by field fabricating a cradle of angle iron and threaded rod. Secure the furnace with 2” (51mm)
minimum slotted angle or equivalent as shown in Figure 3. The furnace must be supported in such a way as to
not allow twisting or sagging of the cabinet. Position the supports so as to not interfere with accessing the burner
and blower compartments.
IMPORTANT:
• THE FURNACE MUST BE INSTALLED ON A LEVEL SURFACE. IT IS RECOMMENDED
THAT THE REAR OF THE FURNACE BE ELEVATED 1/4” (6mm) HIGHER THAN THE
FRONT TO FACILITATE PROPER CONDENSATE DRAINAGE.
• IF THE FURNACE AND AIR CONDITIONER IS LOCATED ABOVE A FINISHED SPACE,
INSTALL A DRAIN PAN UNDERNEATH THE UNIT.
NOTE
This furnace is approved for installation in attics, alcoves, utility rooms, closets and crawl spaces. If this
furnace is to be installed in a utility room, be sure that it is located in such a way as to allow access for
servicing or the removal of other appliances installed in the room (hot water heater, for example). It is not
permissible to use a rear return on this appliance. Use only side and bottom returns.

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4.4 AIR CONDITIONING
5.0 COMBUSTIBLE CLEARANCES
H8.4.1
This furnace may be used as part of an air conditioning system. The furnace wiring and control system is “air
conditioning ready.” There are the following factors to consider:
The air conditioning evaporator coil must be downstream of the heat exchanger. The cooled air passing
over the warmer heat exchanger tubes can cause condensation inside the tubes, resulting in corrosion and
premature failure.
A parallel duct system can be installed to direct the air from the furnace through the evaporator coil only. Use
dampers or other means to bypass the heat exchanger. If (summer/winter) dampers are used, they should be
interlocked to prevent system operation unless the dampers are in the full open or full closed position.
Optional Bridge Installation Kit (W370-0028), available to run heat and cool speeds on shared tap.
H9.0
Table B provides the certified clearances to combustibles information. Also see the appliance rating plate
affixed to the furnace for specific model number, serial number and clearance to combustibles information.
IMPORTANT:
THIS FURNACE REQUIRES A MINIMUM OF 24" (610mm) OF FRONT CLEARANCE FOR
SERVICE PURPOSES. FOR THIS PURPOSE, SERVICE CLEARANCE TAKES PRECE-
DENCE OVER CLEARANCE TO COMBUSTIBLES.
H3.7
THIS FURNACE IS CERTIFIED FOR INSTALLATION ON COMBUSTIBLE FLOORS. THIS
SHALL BE INTERPRETED AS A WOOD FLOOR ONLY.
THE FURNACE MUST NOT BE INSTALLED DIRECTLY ON CARPETING, OR OTHER
COMBUSTIBLE MATERIAL EXCEPT WOOD.
INSTALLATION ON COMBUSTIBLE MATERIAL CAN RESULT IN FIRE, CAUSING PROPERTY
DAMAGE, PERSONAL INJURY OR DEATH.
THE AREA AROUND THE FURNACE MUST BE KEPT CLEAR AND FREE OF ALL
COMBUSTIBLE MATERIALS INCLUDING GASOLINE AND OTHER FLAMMABLE VAPORS
AND LIQUIDS.
THE HOMEOWNER SHOULD BE CAUTIONED THAT THE FURNACE AREA MUST NOT BE
USED AS A CLOSET OR FOR ANY OTHER STORAGE PURPOSE.
WARNING !!

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6.0 DUCTWORK
H10.0
Proper airflow is required for the correct operation of this furnace. Insufficient airflow may cause erratic
operation, could cause the furnace to cycle on the high temperature limit, and may damage the heat
exchanger. Excessive airflow may result in an excessively noisy duct system and may result in undesirable
consequences such as creating uncomfortable drafts.
If air conditioning is to be used with the furnace, the duct system must be capable of delivering the correct
amount of airflow for each system.
The ductwork should be sized and constructed in accordance with accepted industry standards. Duct sizing
and construction information may be obtained from:
• A.C.C.A. (Air Conditioning Contractors of America)
• A.S.H.R.A.E. (American Society of Heating, Refrigeration and Air Conditioning Engineers)
• H.R.A.I. (Heating, Refrigerating and Air Conditioning Institute (Canada)
• S.M.A.C.N.A. (Sheet Metal and Air Conditioning Contractors’ National Association (United States)
All of the above professional organizations have duct sizing manuals available.
The total static pressure drop of the air distribution system (including filters) should not exceed 1.0” w.c.
H3.8
DO NOT ALLOW GAS PIPING TO BE ROUTED THROUGH JOIST SPACES THAT ARE
USED FOR RETURN AIR PURPOSES. DO NOT USE JOIST SPACES FOR RETURN AIR
PURPOSES IF THE JOIST SPACE ALREADY CONTAINS PLUMBING STACKS, CHIMNEY
COMPONENTS, ETC. UNLESS THE PORTION USED FOR RETURN AIR PURPOSES CAN
BE COMPLETELY ISOLATED FROM PORTIONS WITH OTHER USAGES.
NEVER ALLOW THE PRODUCTS OF COMBUSTION FROM THE FLUE TO ENTER THE
RETURN AIR OR SUPPLY AIR DUCTWORK.
ALL RETURN AIR DUCTWORK MUST BE ADEQUATELY SEALED AND SECURED TO
THE FURNACE WITH SHEET METAL SCREWS. TAPE THE SHEET METAL SEAMS IN THE
VICINITY OF THE FURNACE WITH DUCT TAPE OR SIMILAR MATERIAL.
WHEN THE FURNACE IS MOUNTED ON A PLATFORM WITH RETURN AIR THROUGH THE
BOTTOM, IT MUST BE SEALED AIR TIGHT BETWEEN THE FURNACE AND THE RETURN
AIR PLENUM. THE FLOOR OR PLATFORM MUST PROVIDE SOUND PHYSICAL SUPPORT
OF THE FURNACE WITHOUT SAGGING OR GAPS AROUND THE BASE. IT MUST ALSO
BE SEALED BETWEEN THE SUPPORT AND THE BASE.
FAILURE TO PREVENT PRODUCTS OF COMBUSTION FROM BEING CIRCULATED INTO
THE LIVING SPACE CAN CREATE POTENTIALLY HAZARDOUS CONDITIONS, INCLUDING
CARBON MONOXIDE POISONING THAT COULD RESULT IN PERSONAL INJURY OR
DEATH.
WARNING !
!

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6.1 DUCTWORK STEPS
H10.1
1. Position the furnace to minimize ductwork length and fittings.
2. Cut open a return air inlet. The choices are furnace bottom, either side, or any combination thereof (i.e.,
two sides or a side and the bottom).In all cases, cut the return air opening the full width of the return air
markers on the side panel.
NOTE: If the airflow requirements exceed 1800 cfm, models will require air openings and filters on:
• both sides, OR
• one side and the bottom, OR
• just the bottom
3. Connect the return air duct or filter fitting to the furnace. The connection should be sealed air tight to prevent
entraining combustion gases from an adjacent fuel burning appliance, or entraining combustion air for this
furnace or adjacent fuel burning appliances.
4. Ensure that there is adequate space and accessibility for air filter removal.
5. If an air conditioning evaporator coil is required, position it on the supply air side of the furnace. Ensure
that no air can bypass the evaporator coil.
6. Connect the supply air plenum to the supply air outlet.
FLEXIBLE DUCT CONNECTORS are an effective device to prevent the telegraphing of mechanical noise from
the furnace to other parts of the home via the ductwork. If using flexible connectors, ensure that the adjoining
duct is independently supported.
H3.9
DO NOT USE THE REAR PANEL AS A RETURN AIR INLET. THERE IS INSUFFICIENT
ROOM TO PERMIT ADEQUATE AIRFLOW.
DAMAGES, DEFECTS OR FAILURES CAUSED BY CONDITIONED AIR (RETURN AIR)
SUPPLIED TO THE FURNACE BEING GREATER THAN 20% FROM OUTDOORS (55°F/13°C
MIN. RETURN AIR TEMPERATURE).
SOME HEATING AIR FLOW VALUES MAY BE HIGHER THAN THOSE REQUIRED FOR
COOLING. BE SURE TO SIZE DUCT SYSTEM FOR HIGHEST POSSIBLE VALUES.
WARNING !
!

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7.2 ACCEPTABLE MATERIALS IN UNITED STATES
7.0 VENTING AND COMBUSTION PIPING
7.1 ACCEPTABLE MATERIALS IN CANADA
H3.10
READ, UNDERSTAND AND FOLLOW ALL INSTRUCTIONS IN THIS SECTION. FAILURE TO
PROPERLY VENT OR SUPPLY COMBUSTION AIR TO THIS FURNACE CAN CAUSE CAR-
BON MONOXIDE POISONING, OR AN EXPLOSION OR FIRE, RESULTING IN PROPERTY
DAMAGE, PERSONAL INJURY OR LOSS OF LIFE.
WARNING !
!
H11.1
Effective August 1, 2007, all vent piping materials and fittings for flue gas venting must be ULC S636 listed
and identified as such on the material. The first 3ft. (900mm) of venting must be readily available for visual
inspection. Specified primers and glues of the certified vent system must be from a single system manufacture,
and not intermixed with other system manufacture’s vent system parts. The components of the certified vent
system must not be interchanged with other vent systems, or unlisted pipe, and or fittings. Follow the venting
manufacturers instructions on installation, cutting, de-burring, cementing, curing and supporting of the venting
system.
This furnace must be vented with ULC S636 certified:
• PVC (Polyvinyl Chloride), OR
• PPE (Polypropolene) material
with a rating of 149°F (65ºC) or more.
The combustion air piping does not have flue gases travelling through it and may be installed with common
ABS, PVC or CPVC piping or fittings. This piping, fittings, primer and cement will need to be installed as per
the manufacturers instructions including cementing, cutting, curing and supporting the piping.
H11.2
For United States installations, the combustion air and vent piping and fittings may be comprised of:
• Schedule 40 PVC, ASTM D1785 or CSA B137.3
• PVC-DWV, ASTM D2665 or CSA B181.2
• Schedule 40 CPVC, ASTM F441 or CSA B137.6
• PVC PRIMER AND SOLVENT CEMENT: ASTM D2564
• PPE ULC S636
Follow piping manufacturers instructions on proper installation of piping and fittings including cutting, deburring
,
priming, cementing, curing and supporting.

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7.3 VENT DRAIN OPTION
H11.3
A vent drain is recommended when vent passes through any unconditioned space such as an attic or crawl
space in order to prevent the accumulation of excess condensate in the inducer housing during operational
cycles, refer to images for Vent Drain Option.
To install the vent drain, complete the following steps:
IMPORTANT: Tee, reducer and nipple must be properly
cemented together using the appropriate method
and materials specified in section 7.0 Venting and
Combustion Piping; 7.1 Acceptable Materials in Canada
and 7.2 Acceptable Materials in United States.
1. Place a tee of the proper diameter for the vent system
being installed 2" (51mm) or 3" (76mm) in the horizontal run
or vertical riser closest to the furnace.
2. Place a reducer bushing of proper diameter in the stem
portion of the tee. The recommended size for the reducer is
5/8" (15.9mm).
3. Place a piece of 5/8" (15.9mm) diameter pipe that has a
minimum length of 3" (76mm) long into the reducer to serve
as a nipple.
4. Connect a piece of flexible drain tubing such as EPDM
rubber or PVC to the nipple.
5. Loop the drain tubing to provide a trap.
6. Connect the discharge end of the drain tube to the
condensate disposal system externally to the furnace.
IMPORTANT:
ELBOWS WITH DRAIN PORTS
ARE NOT RECOMMENDED, AS
CONDENSATE CAN BYPASS THE
DRAIN ON THE CURVE.
1/2" (12.7mm) ID MAX.
3" (76mm) MIN.
10" (254mm) MAX.
LOOP DIAMETER
ATTACH THIS END TO
CONDENSATE DRAIN
SYSTEM
3" (76mm) MIN.
10" (254mm) MAX.
LOOP DIAMETER
ATTACH THIS END TO
CONDENSATE DRAIN
SYSTEM
1/2" (12.7mm) ID MAX.
USE SWEEP TEE ON
HORIZONTAL LINE

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8.0 NON-DIRECT VENT FURNACE INSTALLATIONS
USING INDOOR COMBUSTION AIR (ONE PIPE
SYSTEM)
H13.0
The furnace, although designed as a direct vent type appliance, may be installed with the intake vent inside th
e
structure.
Adequate provisions for combustion and ventilation air must be in accordance with CAN/CGA-B149 in Canada,
and ANSI Z223.1 - 1992, section 5.3, “Air for Combustion and Ventilation,” in the United States. Check with
local authorities for any additional building codes bylaws or regulations.
AIR FOR COMBUSTION AND VENTILATION PURPOSES MUST NOT ORIGINATE FROM A
CORROSIVE ATMOSPHERE. ANY FURNACE FAILURE CAUSED BY CORROSIVE ELEMENTS IS
EXCLUDED FROM WARRANTY COVERAGE.
CAUTION !
!
The following types of installation sites (but not limited to the following) will REQUIRE OUTDOOR AIR for
combustion because of chemical exposures:
• Commercial buildings
• Buildings with indoor swimming pools
• Furnaces installed in laundry rooms
• Furnaces in hobby or craft rooms
• Furnaces installed near chemical storage areas
Exposure to the following substances in the combustion air supply (but not limited to the following) will also
require OUTDOOR AIR for combustion:
• Aerosols, particularly CFC based or propelled aerosols
• Air fresheners
• “Airplane Glue” and similar adhesives and cements
• Ammonia, as commonly found in permanent wave solutions used in hair dressing salons
• Anti-static fabric softeners used in clothes dryers
• Carbon tetrachloride
• Chlorinated cleaners and waxes
• Chlorine and bromine based swimming pool chemicals
• De-icing salts or chemicals (rock salt, etc.)
• Dry cleaning fluids such as perchloroethylene
• Fumes from curing polyurethane and similar substances
• Halogen based refrigerants including R-12 and R-22
• Hydrochloric acid, muriatic acid and other acid based masonry washing and curing materials
• Printer’s inks, paint removers, varnishes, varsol, toluene, etc.
• Water softener salt and chemicals
Combustion air must be free of acid forming chemicals such as sulphur, fluorine and chlorine. These elements
are found in aerosol sprays, detergents, bleaches, cleaning solvents, air fresheners, paint and varnish
removers, refrigerants, and many other commercial and household products. When burned in a gas flame,
vapors from these products form acid compounds. Acid compounds increase the dew point temperature of the
flue products and are highly corrosive after they condense.
H3.11
THIS FURNACE AND ANY OTHER FUEL BURNING APPLIANCE MUST BE PROVIDED
WITH ENOUGH FRESH AIR FOR PROPER COMBUSTION AND VENTILATION OF THE
FLUE GASES. MOST HOMES WILL REQUIRE THAT OUTSIDE AIR BE BROUGHT TO
THE FURNACE AREA. FAILURE TO DO SO CAN CAUSE PERSONAL INJURY, OR DEATH
FROM CARBON MONOXIDE POISONING.
WARNING !
!

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8.1 DETERMINING COMBUSTION AIR
8.1.1 CASE 1: FURNACE LOCATED IN A UNCONFINED SPACE
8.1.2 CASE 2: FURNACE LOCATED IN A CONFINED SPACE
H13.1
Unconfined space does not necessarily mean that ventilation will not have to be introduced from the outdoors,
particularly in airtight homes. The minimum requirement for unconfined space is a volume of 50 cubic feet (1.42
m³) for each 1000 Btu/hr for all fuel burning appliances located within the unconfined area.
If the amount of combustion and ventilation air is insufficient to properly operate the furnace and other fuel
burning appliances within the unconfined area, it will be necessary to supply it from the outdoors based on the
criteria used when calculating the air supply for a confined space.
NOTE
If planning to use the inside air in an unconfined space, remember to test for proper furnace operation (as well
as other fuel burning appliances located within the unconfined space) with respect to adequate combustion and
ventilation air with fireplace dampers open, clothes dryer running, bathroom exhaust fans on, kitchen range hood
on, etc.
H13.2
A confined space, (any space smaller than the minimums discussed in Case 1), must have two air openings;
one within 12” (305mm) of the ceiling and the other within 12” (305mm) of the floor. The air openings must
be sized based on whether the combustion and ventilation air is being taken from indoors or outdoors, the
method outdoor air (if used) is introduced, and taking into account any other fuel burning appliances in the
confined space.
If sufficient indoor combustion and ventilation air is available for the furnace and all other fuel burning
appliances, size each opening on the basis of one square inch (645mm²) of free area per 1000 Btu/hr.
(Figure 4)
NOTE
Be sure to consider all clothes dryers, bathroom fans, range hoods, etc., when making this calculation.
The minimum requirement for these openings is 100
square inches (645mm²), even for the furnace models
under 100,000 Btu/hr.
NOTE
If using grills to cover the two openings, factor in the
free area of the grill. Typically, a sidewall grill will
have a free area approximately 50% of its nominal
size. Consequently, if the required opening is 10" x
10" (254mm x 254mm), it will have to be doubled if
using a sidewall grill with 50% free area.
IMPORTANT:
IF AN EXHAUST FAN, FIREPLACE, CLOTHES DRYER OR ANY SIMILAR DEVICE IS PRESENT IN THE
INDOOR AREA FROM WHICH THE COMBUSTION AND VENTILATION AIR WILL BE DRAWN, NEGA-
TIVE PRESSURE COULD BE A PROBLEM IF NATURAL INFILTRATION FROM THE OUTDOORS DOES
NOT MATCH THE RATE AT WHICH AIR IS EXHAUSTED.
FIGURE 4 - COMBUSTION/DILUTION AIR FROM
HEATED INSIDE SOURCES (CASE 2)

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8.1.3 CASE 3: FURNACE LOCATED IN A CONFINED SPACE, OUTDOOR AIR
FROM ATTIC OR CRAWL SPACE
H13.3
FIGURE 5 - OUTSIDE AIR FOR COMBUSTION, ATTIC OR
CRAWL SPACE (CASE 3)
Alternate Combustion Air
from Attic. (12”/ 305 mm
above oor)
In this circumstance, the free area of each of the two combustion and ventilation air openings is based on a
minimum of 1 square inch (645mm²) per 4000 Btu/hr. In this configuration, one opening can originate from the
floor drawing combustion and ventilation air from the ventilated crawl space.
The other opening may communicate freely with the ventilated attic. If using the attic air, ensure that the
opening is ducted from the ceiling high enough to be above the insulation. The attic must be adequately
vented with soffit vents or gable vents (Figure 5).
As an alternative to creating an opening in the floor to draw air from a crawl space, a duct may be dropped from
the attic terminating 12” (305mm) above the floor.
The following table shows minimum free areas and round pipe sizes when drawing combustion air vertically
from the attic or crawl space for the furnace
only. If other fuel burning appliances are
present, their combustion air and ventilation
air requirements must be added to those of
the furnace.
IMPORTANT:
IF THE ATTIC HAS AN EXHAUST FAN (POWER VENT), IT MAY CREATE A NEGATIVE
PRESSURE SUFFICIENTLY LARGE ENOUGH TO PREVENT THE ATTIC FROM BEING
AN EFFECTIVE SOURCE OF COMBUSTION AND VENTILATION AIR. POWERED ATTIC
FANS DO NOT CUSTOMARILY RUN DURING THE HEATING SEASON; HOWEVER,
SOME ARE CONTROLLED BY A HUMIDISTAT AS WELL AS A THERMOSTAT, WHICH MAY
ALLOW SOME OPERATION DURING THE HEATING SEASON. THE CHOICES ARE (A)
USE THE DIRECT VENT OPTION; (B) OBTAIN OUTDOOR AIR FROM ELSEWHERE; OR
(C) INTERLOCK THE ATTIC EXHAUST FAN WITH THE FURNACE SUCH THAT THE TWO
CANNOT OPERATE SIMULTANEOUSLY.
TABLE 2 - VERTICAL AIR
SUPPLY (CASE 3)
Input
K/Btu/hr Free Area Ea. Opening Round Pipe Size
30
15 in2
(97 cm2)
5 in
(127 mm)
40
60
80 20 in2
(129 cm2)6 in
(152 mm)
100 25 in2
(161 cm2)
120 30 in2
(194 cm2)
7 in
(178 mm)
H12.16.1

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8.1.4 CASE 4: FURNACE LOCATED IN A CONFINED SPACE,
OUTDOOR AIR DUCTED HORIZONTALLY
8.1.5 CONNECTION TO FURNACE NON-DIRECT VENT
TABLE 3 - HORIZONTAL AIR
SUPPLY (CASE 4)
Input
K/Btu/hr Free Area Ea. Opening Round Pipe Size
30
30 in2
(194 cm2)
7 in
(178 mm)
40
60
80 40 in2
(258 cm2)8 in
(203 mm)
100 50 in2
(323 cm2)
120 60 in2
(387 cm2)
9 in
(229 mm)
H12.9.1
H13.4
Similar to Case 3, outdoor air for combustion and ventilation may be drawn through horizontal ducting. The
free area for each opening is calculated on the basis of a minimum of 1 square inch (645mm²) per 2000 Btu/hr
input.
The following table shows minimum free areas and round pipe sizes when drawing combustion air horizontally
from the outdoors for the furnace only. If other fuel burning appliances are present, their combustion air and
ventilation air requirements must be added to those of the furnace.
IMPORTANT:
IF GRILLS ARE USED ON THE OUTSIDE WALL, THEY MUST BE SIZED PROPERLY.
MOST SIDEWALL GRILLS HAVE ONLY 50% FREE AREA. IN THE CASE OF A UNIT WITH
100,000 BTU/HR INPUT, WHICH REQUIRES A PAIR OF 8” (203mm) ROUND PIPES TO
OBTAIN SUFFICIENT COMBUSTION AND VENTILATION AIR, THE DUCT COULD BE AN
EQUIVALENT RECTANGULAR DUCT; 8” X 7” (203mm X 178mm) FOR EXAMPLE. BASED
ON 50% FREE AREA FOR THE INLET GRILLS, THE ACTUAL GRILL SIZE WOULD HAVE
TO BE 14” X 8” (356mm X 203mm) OR ITS EQUIVALENT. A TRANSITION MAY BE USED TO
REDUCE TO THE SMALLER DUCT SIZE IF NECESSARY.
IMPORTANT:
THE OUTDOOR GRILLS MUST BE INSTALLED IN A LOCATION WHERE THEY WILL NOT BE
OBSTRUCTED IN ANY MANNER.
Combustion Air
Duct Terminates
12” (305mm)
above oor.
FIGURE 6 - OUTDOOR AIR FOR COMBUSTION,
HORIZONTAL (CASE 4)
H13.5
FIGURE 7 - NON-DIRECT
COMBUSTION AIR INLET
IMPORTANT:
WHEN USING INDOOR AIR OR THE NON-DIRECT
VENT CONFIGURATION, THE COMBUSTION AIR
INLET TO THE FURNACE MUST BE PROTECTED
FROM BLOCKAGE. USE A DOUBLE ELBOW
ARRANGEMENT IF SUPPLYING COMBUSTION AIR
THROUGH THE TOP, OR A DOWNWARD POINTING
SINGLE ELBOW IF SUPPLYING COMBUSTION AIR
THROUGH THE SIDE. (FIGURE 7)