Ingersoll-rand M951p040bu24aa Assembly instructions

Upﬂow/Horizontal, Downﬂow/ Horizontal, Gas-Fired, Direct Vent

Condensing Furnaces

INSTALLER'S GUIDE

M95 Upﬂow models can also be used in the

Horizontal Left conﬁguration.

M95 Downﬂow models can also be used in the

Horizontal Right conﬁguration.

A341624P16

M95 Furnace

18-CD35D1-4

OPTIONAL ACCESSORIES

Model Number Description

BAYBASE205 Downﬂow subbase for downﬂow models only

BAYFLTR200 External side ﬁlter rack

BAYFLTR203 Filter kit horizontal for 17.5" cabinet

BAYFLTR204 Filter kit horizontal for 21" cabinet

BAYFLTR205 Filter kit horizontal for 24.5" cabinet

BAYFLTR317 Cleanable ﬁlter for 17.5" cabinet upﬂow only

BAYFLTR321 Cleanable ﬁlter for 21" cabinet upﬂow only

BAYFLTR324 Cleanable ﬁlter for 24.5" cabinet upﬂow only

BAYLPKT210B Propane conversion kit

BAYLPSS210B LP kit with stainless steel burners

BAYMFGH100A Manufactured / mobile home kit

BAYRACK960A Internals ﬁlter rack kit for upﬂow models

BAYAIR30AVENTA Concentric vent kit for 2,2.5,3" vent system

BAYVENT200B Sidewall vent termination kit for direct vent furnaces

BAYVENT500A Side vent kit for downﬂow models only

BAYSWT01AHALTA High altitude switch kit - UF/DF 040, DF 085

BAYSWT04AHALTA High altitude switch kit - UF 060, 100, UF 120

BAYSWT05AHALTA High altitude switch kit - UF 080, 100, DF 110

BAYSWT12AHALTA High altitude switch kit - DF 065

KIT09224 Filter clip kit

BAYBRCKFLT10 Downﬂow bracket kit

ALL phases of this installation must comply with

NATIONAL, STATE AND LOCAL CODES

IMPORTANT—This Document is customer property and is to

remain with this unit. Please return to service

information pack upon completion of work.

M951P040BU24AA

M951P060BU36AA

M951P080BU42AB

M951P100CU48AA

M951P100DU60AA

M951P120DU60AA

M951P040BD24AA

M951P065BD42AA

M951P085CD48AA

M951P110DD60AA

2 18-CD35D1-4

INSTALLER’S GUIDE

INSTALLATION INSTRUCTIONS

SAFETY SECTION

The following safety practices and precautions must be followed

during the installation, servicing, and operation of this furnace.

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

Refer to the furnace rating plate.

2. Install this furnace only in a location and position

as specied in “Location and Clearances” of these

instructions.

3. Provide adequate combustion and ventilation air to the

furnace space as specied in “Air for Combustion and

Ventilation” of these instructions.

4. Combustion products must be discharged outdoors.

Connect this furnace to an approved vent system only, as

specied in the “Venting” section of these instructions.

5. Never test for gas leaks with an open ame. Use a

commercially available soap solution made specically

for the detection of leaks to check all connections, as

specied in “Gas Piping” of these instructions.

6. Always install the 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, as specied on the unit rating plate.

Airow with temperature rise for CFM versus static is

found in Service Facts document M951-SF-x.

7. When a furnace is installed so that supply ducts carry

air circulated by the furnace to areas outside the space

containing the furnace, the return air shall also be

handled by a duct(s) sealed to the furnace casing and

terminating outside the space containing the furnace.

8. A gas-red furnace for installation in a residential

garage must be installed as specied in “Location and

Clearances” section, of these instructions.

9. The furnace may be used for temporary heating of

buildings or structures under construction only when

the following conditions have been met:

The furnace venting system must be complete and

installed per manufacturer’s instructions.

The furnace is controlled only by a room thermostat

(no eld jumpers).

The furnace return air duct must be complete and

sealed to the furnace and clean air lters are in

place.

The furnace input rate and temperature rise must be

veried to be within nameplate marking.

100% of the furnace combustion air requirement

must come from outside the structure.

The furnace return air temperature range is between

55 and 80 degrees Fahrenheit.

Clean the furnace, duct work, and components upon

substantial completion of the construction process,

and verify furnace operating conditions including

ignition, input rate, temperature rise and venting,

according to the manufacturer’s instructions.

10. This product must be gas piped by a Licensed Plumber

or Gas Fitter in the Commonwealth of Massachusetts.

▲

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow the steps outlined below for

each appliance connected to the venting system

being placed into operation could result in carbon

monoxide poisoning or death.

The following steps shall be followed for each appliance

connected to the venting system being placed into

operation, while all other appliances connected to the

venting system are not in operation:

Seal any unused openings in the venting

system.

1. Inspect the venting system for proper size and

horizontal pitch, as required in the National Fuel Gas

Code, ANSI Z223.1/NFPA 54 or the CAN/CGA B149

Installation Codes and these instructions. Determine

that there is no blockage or restriction, leakage,

corrosion and other deﬁciencies which could cause

an unsafe condition.

2. As far as practical, close all building doors and

windows and all doors between the space in which

the appliance(s) connected to the venting system are

located and other deﬁciencies which could cause an

unsafe condition.

3. Close ﬁreplace dampers.

4. Turn on clothes dryers and any appliance not

connected to the venting system.Turn on any exhaust

fans, such as range hoods and bathroom exhausts, so

they are operating at maximum speed. Do not operate

a summer exhaust fan.

5. Follow the lighting instructions. Place the appliance

be-ing inspected into operation. Adjust the thermostat

so appliance is operating continuously.

6. If improper venting is observed during any of the

above tests, the venting system must be corrected

in accordance with the National Fuel Gas Code,

ANSI Z221.1/NFPA 54 and/or CAN/CGA B149

Installation Codes.

7. After it has been determined that each appliance

connected to the venting system properly vents where

tested as outlined above, return doors, windows,

exhaust fans, ﬁreplace dampers and any other gas-

ﬁred burning appliance to their previous conditions of

use.

18-CD35D1-4 3

INSTALLER’S GUIDE

INSTALLATION INSTRUCTIONS..........2

General Installation Instructions ....................................... 3

Location and Clearances.................................................. 4

Outline Drawings .............................................................. 5

Upﬂow Installation ............................................................ 7

Downﬂow Installation........................................................ 7

Horizontal Installation ....................................................... 7

Air for Combustion and Ventilation.................................... 8

Duct Connections ........................................................... 10

Return Air Filters ............................................................ 11

General Venting .............................................................. 12

Venting Material.............................................................. 13

Venting Tables................................................................. 14

Horizontal Venting........................................................... 16

Horizontal Venting Through Wall..................................... 16

Venting Through Roof..................................................... 18

Venting Through A Masonry Chimney ............................ 21

Downward Venting.......................................................... 21

Electrical Connections.................................................... 27

Gas Piping...................................................................... 29

Combustion and Input Check ......................................... 30

START UP AND ADJUSTMENT..........33

Preliminary Inspections .................................................. 33

Lighting Instructions ....................................................... 33

Sequence of Operation................................................... 34

Control and Safety Switch Adjustments ......................... 34

Airﬂow Adjustment.......................................................... 34

ABNORMAL CONDITIONS .................36

IFC Error Flash Code ..................................................... 36

GENERAL INSTALLATION

INSTRUCTIONS

The manufacturer assumes no responsibility for equipment

installed in violation of any code or regulation.

It is recommended that Manual J of the Air Conditioning

Contractors Association (ACCA) or A.R.I. 230 be followed

in estimating heating requirements. When estimating heating

requirements for installation at altitudes above 2000 ft.,

remember the gas input may need to be reduced (See High

Altitude Installation).

Material in this shipment has been inspected at the factory

and released to the transportation agency without known

damage. Inspect exterior of carton for evidence of rough

handling in shipment. Unpack carefully after moving

equipment to approximate location. If damage to contents

is found, report the damage immediately to the delivering

agency.

Codes and local utility requirements governing the installation of

gas red equipment, wiring, plumbing, and ue connections must

be adhered to. In the absence of local codes, the installation must

conform with latest edition of the National Fuel Gas Code ANSI

Z223.1 • National Installation Code, CAN/CGA B149.1. The

latest code may be obtained from the American Gas Association

Laboratories, 400 N. Capitol St. NW, Washington D.C. 20001.

1-800-699-9277 or www.aga.org

These furnaces have been classied as CATEGORY IV furnaces

in accordance with latest edition of ANSI Z21.47 • CAN/ CGA

2.3 standards.

Category IV furnaces operate with positive vent static pressure

and with a ue loss less than 17 percent. These conditions require

special venting systems, which must be gas tight and water

tight. These Category IV Direct Vent furnaces are approved for

installation in Manufactured/ Mobile housing when used with

BAYMFGH100A.

▲WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow the 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.

Safety signal words are used to designate a degree or level of

seriousness associated with a particular hazard. The signal

words for safety markings are WARNING and CAUTION.

WARNING indicates a potentially hazardous

situation which, if not avoided, could result in death

or serious injury.

CAUTION indicates a potentially hazardous

situation which, if not avoided, may result in minor

or moderate injury. It is also used to alert against

unsafe practices and hazards involving only property

damage.

Contents

4 18-CD35D1-4

INSTALLER’S GUIDE

LOCATION AND CLEARANCES

The location of the furnace is normally selected by the architect,

the builder, or the installer. However, before the furnace is moved

into place, be sure to consider the following requirements:

1. Is the location selected as near the vent and as centralized

for heat distribution as practical?

2. Do all clearances between the furnace and enclosure

equal or exceed the minimums shown in the Table 1.

3. Is there sufcient space for servicing the furnace and other

equipment? A minimum of 24 inches front accessibility

to the furnace must be provided. Any access door or

panel must permit removal of the largest component.

4. Are there at least 3 inches of clearance between the

furnace front panel and any closed panel or door

provided?

5. Are the ventilation and combustion air openings large

enough and will they remain unobstructed? If outside

air is used, are the openings set 12" minimum above

the highest snow accumulation level (18" in Canadian

applications)?

6. Allow sufcient height in supply plenum above or below

the furnace to provide for cooling coil installation if the

cooling coil is not installed at the time of this furnace

installation.

7. A furnace shall be installed so electrical components are

protected from water.

8. If the furnace is installed in a residential garage, it must

be installed so that the burners and the ignition source are

located not less than 18 inches (46 cm) above the oor

and the furnace must be located or protected to avoid

physical damage from vehicles.

IMPORTANT: The furnace must be installed

level. The only allowable variation would be

slightly to the left and/or forward in upﬂow

installations or slightly toward the front in

horizontal installations. This is necessary for

proper condensate drainage.

NOTE: On upﬂow 5 ton airﬂow models where the

airﬂow requirement exceeds 1800 CFM - Models

will require return air openings and ﬁlters on: (1)

both sides; or (2) one side and the bottom; or (3)

just the bottom.

▲

CAUTION

To prevent shortening its service life, the furnace

should not be used as a “Construction Heater”

during the ﬁnishing phases of construction

until the requirements listed in item 9, a-g of the

safety section of this publication have been met.

Condensate in the presence of chlorides and

ﬂuorides from paint, varnish, stains, adhesives,

cleaning compounds, and cement create a

corrosive condition which may cause rapid

deterioration of the heat exchanger.

▲

CAUTION

Do NOT install the furnace in a corrosive or

contaminated atmosphere.

▲WARNING

EXPLOSION HAZARD!

PROPANE GAS IS HEAVIER THAN AIR AND MAY

COLLECT IN ANY LOW AREAS OR CONFINED

SPACES. IN ADDITION, ODORANT FADE MAY

MAKE THE GAS UNDETECTABLE EXCEPT WITH

A WARNING DEVICE. IF THE GAS FURNACE IS

INSTALLED IN A BASEMENT, AN EXCAVATED

AREA OR A CONFINED SPACE, IT IS STRONGLY

RECOMMENDED TO CONTACT A GAS SUPPLIER

TO INSTALL A GAS DETECTING WARNING

DEVICE IN CASE OF A GAS LEAK.

NOTE: The manufacturer of your furnace does not

test any detectors and makes no representations

regarding any brand or type of detector

18-CD35D1-4 5

INSTALLER’S GUIDE

M95 OUTLINE DRAWING, UPFLOW / HORIZONTAL

(ALL DIMENSIONS ARE IN INCHES)

1. DIAMETER OF VENT PIPE MAY BE LIMITED TO 2-1/2” OR 3”

ON SOME MODELS AT DIFFERENT ALTITUDES. REFER TO THE

VENT LENGTH TABLE FOR PROPER APPLICATION.

MODEL DIM "A" DIM"B" DIM "C" DIM "D" DIM "E" DIM "F"

M951P040BU24AA*

M951P060BU36AA*

M951P080BU42AB*

17-1/2" 2-1/4" 16-1/4" 16" 7-1/2" 2"

M951P100CU48AA* 21" 2-1/2" 19-3/4" 19-1/2" 9" 3"

M951P100DU60AA*

M951P120DU60AA* 24-1/2" 2-15/16" 23-1/4" 23" 10" 3"

*15th digit is a service code and may be A-Z

6 18-CD35D1-4

INSTALLER’S GUIDE

M95 OUTLINE DRAWING, DOWNFLOW / HORIZONTAL

(ALL DIMENSIONS ARE IN INCHES)

MODEL DIM "A" DIM"B" DIM "C" DIM "D"

M951P040BD24AA*

M951P065BD42AA* 17-1/2" 2-1/4" 16-1/4" 16"

M951P085CD48AA* 21" 2-1/2" 19-3/4" 19-1/2"

M951P110DD60AA* 24-1/2" 2-15/16" 23-1/4" 23"

*15th digit is a service code and may be A-Z

18-CD35D1-4 7

INSTALLER’S GUIDE

UPFLOW INSTALLATION

The cased coil must be secured to the furnace and both the

furnace and the cased coil must be properly supported.

The coil is always placed downstream of the furnace airow.

DOWNFLOW INSTALLATION

▲

WARNING

Do NOT install the furnace directly on carpeting,

tile or other combustible material other than

wood ﬂooring. For vertical downﬂow application,

subbase (BAYBASE205) must be used between

the furnace and combustible ﬂooring. When the

downﬂow furnace is installed vertically with a

cased coil, a subbase is not required.

Required oor opening:

SUBBASE CROSS SECTION

TABLE 1

CABINET

WIDTH

RETURN

DUCT

WIDTH

FLOOR OPENING PLENUM OPENING

"A" "B" "C" "D"

17-1/2" 16-1/4" 16-5/8" 20-1/8" 15-5/8" 19-3/8"

21" 19-3/4" 20-1/8" 20-1/8" 19-1/8" 19-3/8"

24-1/2" 23-1/4" 23-5/8" 20-1/8" 22-5/8" 19-3/8"

FURNACE

FRONT

A (width)

B (depth)

HORIZONTAL INSTALLATION

The coil and furnace must be fully supported when used in the

horizontal position. It is always recommended that an auxiliary

drain pan be installed under a horizontally installed evaporator

coil or 95% gas furnace. Connect the auxiliary drain line to a

separate drain line (no trap is needed in this line).

Installing the three brackets (with screws) that are included in

donwow furnaces will stabilize and secure the furnace and

cased coil in the horizontal position. See Figure 4.

IMPORTANT: The cased coil must be placed

downstream of the furnace. In horizontal

installations, the apex of the coil may point

either toward or away from the furnace. See the

coil Installer's Guide for more details.

The cased coil is secured to the furnace and both the furnace and

the cased coil must be properly supported. If used, the brackets

mount using the rear screws on the coil case and use the screws

provided to secure the bracket to the furnace. The remaining

bracket is placed as close to center as possible (horizontally)

between the coil case front and the furnace bottom channel (for

downow/horizontal furnace). Use four of the screws provided to

secure the bracket. The upow furnace, converted to horizontal,

aligns and attaches the coil as in Figure 1. However, the coil

requires additional support.

DOWNFLOW ONLY

CASED COIL CONNECTION

BRACKET FOR DOWNFLOW

FURNACE IN HORIZONTAL

The furnace may be installed in an attic or crawl space in the

horizontal position by placing the furnace on the left side (as

viewed from the front in the vertical position). The horizontal

furnace installation in an attic should be on a service platform

large enough to allow for proper clearances on all sides and

service access to the front of the furnace (See Figure 3 and Table

1). Line contact is only permissible between lines formed by

intersections of the top and two sides of the furnace casing and

building joists, studs, or framing.

8 18-CD35D1-4

INSTALLER’S GUIDE

UPFLOW/

HORIZONTAL

SHOWN

6" Minimum

The furnace may be placed horizontally in a crawl space on a

pad or other noncombustible material which will raise the unit

for sufcient protection from moisture. The furnace must be

supported at both ends and the middle when installed horizontally.

The furnace must also be elevated a minimum of 6 inches to

allow clearance for the condensate drain to exit the cabinet in the

horizontal position.

The horizontal furnace may also be suspended from the joists

using 3/8" all-thread rods with pieces of angle iron underneath

the furnace to form a hanging rack at both ends and the midpoint.

The rods need to be of sufcient length to allow for proper

clearances from combustible materials. The angle iron needs to

be at least 32" in length to allow for access to service panels.

50 CU. FT. OR MORE

PER 1000 BTU/HR. INPUT

ALL EQUIP. INSTALLED

UNCONFINED

AIR FOR COMBUSTION AND

VENTILATION

If these furnaces are installed in a non-direct vent capacity then

the adequate ow of combustion and ventilating air must not be

obstructed from reaching the furnace. Air openings provided for

combustion air must be kept free of obstructions which restrict

the ow of air. Airow restrictions affect the efciency and safe

operation of the furnace. Keep this in mind should you choose

to remodel or change the area which contains your furnace.

Furnaces must have a free ow of air for proper performance.

Provisions for combustion and ventilation air shall be made in

accordance with latest edition of Section 5.3, Air for Combustion

and Ventilation, of the National Fuel Gas Code, ANSI Z223.1 —

CAN/CGA B149.1 or applicable provisions of the local building

codes. Special conditions created by mechanical exhausting of

air and replaces must be considered to avoid unsatisfactory

furnace operation.

OUTSIDE AIR IS RECOMMENDED

The use of indoor air for most applications is acceptable, unless

there is the presence of corrosive chemicals or contamination.

Certain types of installation will require the use of outside air for

combustion.

The following types of installations will require use of

OUTDOOR AIR for combustion, due to chemical exposures:

• Commercial buildings

• Buildings with indoor pools

• Furnaces installed in “conned” laundry rooms

• Furnaces installed in “conned” hobby or craft rooms

• Furnaces installed near chemical storage areas.

Exposure to the following substances in the combustion air

supply will also require OUTDOOR AIR for combustion:

• Permanent wave solutions

• Chlorinated waxes and cleaners

• Chlorine based swimming pool chemicals

• Water softening chemicals

• Deicing salts or chemicals

• Carbon Tetrachloride

• Halogen type refrigerants

• Cleaning solvents (such as perchloroethylene)

• Printing inks, paint removers, varnish, etc.

• Hydrochloric acid

• Cements and glues

• Antistatic fabric softeners for clothes dryers

• Masonry acid washing materials

Furnace locations may be in a “conned space” or an

“unconned space”.

Unconned space is dened in Figure 6. These spaces may

have adequate air by inltration to provide air for combustion

and ventilation. Buildings with tight construction (for example,

weather stripping, heavily insulated, caulked, vapor barrier, etc.)

may need additional air to be provided as described for conned

space.

Conned spaces are installations with less than 50 cu. ft. of

space per 1000 BTU/hr input from all equipment installed, as in

Figure 7. Air for combustion and ventilation requirements can

be supplied from inside the building as in Figure 8 or from the

outdoors, as in Figure 9.

18-CD35D1-4 9

INSTALLER’S GUIDE

TABLE 2

MINIMUM AREA IN SQUARE FEET

FOR UNCONFINED SPACE INSTALLATIONS

FURNACE MAXIMUM

BTUH INPUT RATING

WITH 8 FT. CEILING

MINIMUM AREA IN SQUARE FEET OF

UNCONFINED SPACE

40,000

60,000

80,000

97,000

110,000

250

375

500

625

688

CONFINED

SPACE

1. All air from inside the building as in Figure 8: The

conned space shall be provided with two permanent

openings communicating directly with an additional

room(s) of sufcient volume so that the combined

volume of all spaces meets the criteria for an unconned

space. The total input of all gas utilization equipment

installed in the combined space shall be considered in

making this determination. Refer to Table 2 for minimum

open areas requirements.

2. All air from outdoors as in Figure 9: The conned

space shall be provided with two permanent openings,

one commencing within 12 inches of the top and one

commencing within 12 inches of the bottom of the

enclosure. The openings shall communicate directly, or

by ducts, with the outdoors or spaces (crawl or attic) that

freely communicate with the outdoors. Refer to Table 2,

for minimum open areas requirements.

TABLE 3

MINIMUM FREE AREA IN SQUARE INCHES

EACH OPENING (FURNACE ONLY)

FURNACE

MAXIMUM

BTUH/INPUT

RATING

AIR

FROM

INSIDE

AIR FROM OUTSIDE

VERTICAL

DUCT

HORIZONTAL

DUCT

40,000

60,000

80,000

97,000

110,000

100

110

10 18-CD35D1-4

INSTALLER’S GUIDE

DUCT CONNECTIONS

Air duct systems should be installed in accordance with standards

for air conditioning systems, National Fire Protection Association

Pamphlet No. 90. They should be sized in accordance with ACCA

Manual D or whichever is applicable.

Central furnaces, when used in connection with cooling units, shall

be installed in parallel or on the upstream side of the cooling coil

to avoid condensation in the heat exchanger. With a parallel ow

arrangement, the dampers or other means used to control ow of air

shall be adequate to prevent chilled air from entering the furnace,

and if manually operated, must be equipped with means to prevent

operation of either unit unless the damper is in full heat or cool

position.

On any job, exible connections of nonammable material may be

used for return air and discharge connections to prevent transmission

of vibration. Though these units have been specically designed for

quiet, vibration free operation, air ducts can act as sounding boards

and could, if poorly installed, amplify the slightest vibration to the

annoyance level.

When the furnace is located in a utility room adjacent to the

living area, the system should be carefully designed with returns

to minimize noise transmission through the return air grille.

Although these furnaces are designed with large blowers operating

at moderate speeds, any blower moving a high volume of air will

produce audible noise which could be objectionable when the unit

is located very close to a living area. It is often advisable to route

the return air ducts under the oor or through the attic. Such design

permits the installation of air return remote from the living area

(i.e. central hall).

When the 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 a duct(s) sealed to the

furnace and terminating outside the space containing the furnace.

RETURN AIR DUCT CONNECTION

NOTE:

On upﬂow 5 ton airﬂow models where the

airﬂow requirement exceeds 1800 CFM - Models

will require return air openings and ﬁlters on: (1)

both sides; or (2) one side and the bottom; or (3)

just the bottom.

All return air duct systems should provide for installation of

return air lters.

1. Determine the appropriate position to set the furnace in

order to connect to the existing supply and return ductwork.

NOTE:

Minimum return air temperature is 55° F.

2. Refer to Figure 11 and the M95 Outline Drawing for duct

connection dimensions for various furnaces.

3. The side panels on upow furnaces include locating notches

which may be used as guides for cutting an opening for

return air. Refer to Figure 11 and the Outline Drawings for

duct connection dimensions for specic furnace models.

4. If a 3/4" ange is to be used for attaching the air inlet duct,

add to cut where indicated by dashed lines in Figure 11.

Cut corners diagonally and bend outward to form ange.

5. If anges are not required and a lter frame is installed, cut

along knockout guides.

6. Upow Furnaces: Use the optional lter rack on either

side or on the bottom if the lter is to be used within the

furnace cabinet.

7. When the upow furnace is installed in the horizontal

application and a return duct is attached to the top side as

shown in Figure 10, install the lter in a remote location.

Do not install the lter in the return duct directly above the

furnace in horizontal applications.

▲

WARNING

Do NOT install the ﬁlter in the return duct directly

above the furnace in horizontal applications.Install

the ﬁlter remotely. Installing the ﬁlter directly

above the furnace in horizontal applications may

cause property damage, serious injury or death.

▲WARNING

SAFETY HAZARD

To prevent injury or death due to contact with

moving parts, turn the power to the furnace off

before servicing ﬁlters

Failure to follow the safety warnings exactly could

result in serious injury, death or property damage.

When the upow furnace is installed in the horizontal

application and a close coupled (less than 36") return duct

is attached to the bottom side of the furnace as shown in

Figure 10, securely attach a 1/2" mesh metal hardware cloth

protective screen to the inside bottom of the lter grill to

prevent personal injury from contacting moving parts when

reaching into the return opening to replace the lter.

Close coupled (less than 36") return (lter directly beneath

bottom side return) is not recommended due to noise

considerations.

Downow Furnaces: Brackets must be eld supplied (Figure

12). Order BAYBRCKFLT10 2-FLR01185 for 14.5" models,

2 -FLR01186 for 17.5", 21.5" and 24.5" models.

8. Connect the duct work to the furnace. See the M95

Outline Drawing for supply and return duct size and

location. Flexible duct connectors are recommended to

connect both supply and return air ducts to the furnace.

If only the front of the furnace is accessible, it is

recommended that both supply and return air plenums are

removable.

9. When replacing a furnace, old duct work should be cleaned

out. Thin cloths should be placed over the registers and the

furnace fan should be run for 10 minutes. Don’t forget to

remove the cloths before you start the furnace.

18-CD35D1-4 11

INSTALLER’S GUIDE

FILTER

REMOVE FILTER FROM UPFLOW

FURNACE WHEN RETURN DUCT IS

ATTACHED TO FURNACE TOP SIDE

(HORIZONTAL APPLICATIONS) AS

SHOWN.

Close coupled (less than 36")

return (ﬁlter directly beneath bottom

side return) not recommended due to

noise considerations. If used, securely

attach 1/2" mesh metal hardware cloth

protective screen to the inside bottom of

ﬁlter grill.

*SEE OUTLINE DRAWING

LOCATING

NOTCHES

PROVIDED

FOR SIDE

RETURN

CUTOUT

CUT OUT

FOR SIDE

FILTER

FRONT of

Furnace

TABLE 4

MINIMUM CLEARANCE FROM COMBUSTIBLE MATERIALS

FOR UPFLOW/HORIZONTAL LEFT AND DOWNFLOW/

HORIZONTAL RIGHT FURNACES

UNIT

LOCATION

FURNACE

SURFACE

VERTICAL

CLOSET

HORIZONTAL

CLOSET

HORIZONTAL

ALCOVE /

ATTIC

SIDES 0" 1" 0"

BACK 0" 3" 6"

TOP 1" 1" 1"

FRONT 3" 3" 18"

VENT 0" 0" 0"

NOTE: CLEARANCE REQUIRED AT TOP OF PLENUM IS 1"

RETURN AIR FILTERS

(Filter and lter rack are not supplied with unit)

TYPICAL UPFLOW RETURN AIR FILTER INSTALLATIONS

These furnaces require high velocity type air ﬁlters. The

optional ﬁlters may be located within the furnace blower

compartment for UPFLOW furnaces in either a BOTTOM

or SIDE (left side or right side) return air inlet. Some

optional ﬁlters may need to be trimmed for side or bottom

ﬁlter use. See Figure 13.

Airﬂow

TYPICAL DOWNFLOW FURNACE

RETURN AIR FILTER INSTALLATIONS

Two high velocity type air lters are required for each downow

furnace. Downow furnaces in the horizontal conguration must

have the lters outside of the cabinet.

Typical installations are shown in Figure 12 and 14. Table 5 and 6

provide information for installation of the lter retaining brackets

shipped with downow furnaces.

Airﬂow

Typical Filters of Upﬂow in Horizontal

Typical Filters of Downﬂow Horizontal

Typical Filters in Downﬂow

Airﬂow

BAYBRCKFLT10

Accessory ﬁlter kit BAYFLTR203,

204, or 205 used for Upﬂow

Horizontal furnaces

12 18-CD35D1-4

INSTALLER’S GUIDE

TABLE 5

CABINET

WIDTH

FILTER

SIZE

FILTER BRACKET

LOCATION *

14-1/2" 2 - 14X20X1 12-7/8"

17-1/2" 2 - 16X20X1 14-3/8"

21" 2 - 16X20X1 13-1/8"

24-1/2" 2 - 16X20X1 11-5/8"

* Location dimension is from end of duct to the screw holes for the

bracket.

TABLE 6

CABINET

WIDTH

RETURN

DUCT

WIDTH

FILTER ACCESS

OPENING -

DIMENSION "A"

FILTER ACCESS

OPENING -

DIMENSION "B"

14-1/2" 13-1/4" 12" 14"

17-1/2" 16-1/4" 15" 14"

21" 19-3/4" 19-1/2" 14"

24-1/2" 23-1/4" 22" 14"

GENERAL VENTING

IMPORTANT:

These furnaces may be installed as Direct Vent

(sealed combustion) or as Non-direct vent

(single pipe). The furnaces are shipped DIRECT

VENT with sealed combustion. Please refer to

Table 11 and 12 for maximum vent length.

For DIRECT VENT APPLICATION: The furnaces

must be vented to the exterior of the house and

combustion air MUST come through the inlet air

pipe FROM OUTSIDE AIR.

For NON-DIRECT VENT APPLICATION: The

furnace shall be vented to the exterior of the

house, but combustion air may enter from

the surrounding area as long as combustion

air requirements are met. (See AIR FOR

COMBUSTION AND VENTILATION)

THIS FURNACE MUST BE VENTED TO THE OUTDOORS.

THESE FURNACES ARE INDUCED DRAFT VENTED AND

MUST NOT BE CONNECTED TO ANY VENT SERVING

ANOTHER APPLIANCE. PLEASE NOTE THAT THESE

FURNACES USE POSITIVE-PRESSURE VENT SYSTEMS.

Proper venting is essential to obtain maximum efciency from

a condensing furnace. Proper installation of the vent system

is necessary to assure drainage of the condensate and prevent

deterioration of the vent system.

American Gas Association has certied the design of condensing

furnaces for a minimum of 0" clearance from combustible

materials with a single wall plastic vent pipe.

The recommended system is assembled from 2", 2-1/2", or

3" plastic pipe and ttings (See Table 10). Where the system

is routed to the outdoors through an existing masonry chimney

containing ue products from another gas appliance, or where

required by local codes, then 3" venting of Type 29-4C stainless

steel must be used in place of PVC material.

These furnaces have been classied as CATEGORY IV furnaces

in accordance with the latest edition of ANSI Z21.47 • CAN/

CGA-2.3 Standards. Category IV furnaces operate with positive

vent pressure and with a vent gas temperature less than 140°F

above the dew point. These conditions require special venting

systems, which must be gas tight and water tight.

NOTE:

When an existing furnace is removed from a

venting system serving other gas appliances,

the venting system is likely to be too large to

properly vent the remaining attached appliances.

The following steps shall be followed with each appliance

remaining connected to the common venting system placed in

operation, while the other appliances remaining connected to the

common venting system are not in operation.

1. Seal any unused openings in the common venting system.

2. Visually inspect the venting system for proper size and

horizontal pitch and determine there is no blockage or

restriction, leakage, corrosion or other deciencies which

could cause an unsafe condition.

3. Insofar as is practical, close all building doors and

windows and all doors between the space in which the

appliances remaining connected to the common venting

system are located and other spaces of the building. Turn

on clothes dryers and any appliances not connected to

the common venting system. Turn on any exhaust fans,

such as range hoods and bathroom exhausts, so they will

operate at maximum speed. Do not operate a summer

exhaust fan, close replace dampers.

4. Follow the lighting instructions. Place the appliance

being inspected in operation. Adjust thermostat so

appliance will operate continuously.

5. Test for spillage at the draft hood relief opening after

5 minutes of main burner operation. Use the ame of a

match or candle.

6. After it has been determined that each appliance

remaining connected to the common venting system

properly vents when tested as outlined above, return

door, windows, exhaust fans, replace dampers and any

other gas-burning appliance to their previous conditions

of use.

If improper venting is observed during any of the above tests,

the remaining common venting system must be corrected.

Correction of the remaining common vent system should be

done by referring to the latest edition of the National Fuel Gas

Code (ANSI Z223.1) • CAN/CGA B149.1 Installation Codes

18-CD35D1-4 13

INSTALLER’S GUIDE

or “Exhibit J” of ANSI Z21.47 • CAN/ CGA-2.3 Standards.

The following are general steps to be used to correct or resize

a remaining vent system when a furnace which may not be

common vented is removed from the system:

a. Determine the BTU per hour input of all remaining

appliances attached to the venting system.

b. Determine the diameter, rise, and lateral of the existing

venting system, as well as quantity and type of bends.

c. Use the appropriate tables in the latest edition of

the National Fuel Gas Code (ANSI Z223.1 • CAN/

CGA B149.1 Installation Codes or “Exhibit J” of

ANSI Z21.47 • CAN/ CGA-2.3 Standards. “Exhibit

J” includes examples and drawings of typical venting

systems.

VENTING MATERIAL

PVC VENT FITTING MATERIAL

These ttings are available from your Gas Furnace Distributors.

Straight Pipe Sections, Couplings, 45° Elbows, 60° Elbows, 90°

Elbows, Vent or Sanitary Tee, or other necessary ttings may be

2", 2½", 3", or 4" diameter. The allowable materials are shown

in Table 7.

VENT FITTING MATERIAL – PLASTIC

Gas and liquid tight single wall vent ttings, designed for

resistance to corrosive ue condensate, MUST be used

throughout.

Listed in Table 7 are 2", 2½", 3", and 4" size ttings that meet

these requirements. The materials listed are various grades of

PVC and ABS plastic.

PIPE JOINTS: All joints must be fastened and sealed to prevent

escape of combustion products into the building.

NOTE: It is recommended that the ﬁrst joints

from the furnace be connected and sealed with

high temperature RTV. This will enable the pipes

to be removed later without cutting.

Be sure to properly support these joints.

BONDING OF PVC

Commercially available solvent cement must be used to join the

pipe and ttings. Follow instructions on the container carefully.

Procedure for Cementing Joints:

1. Cut pipe square, remove ragged edges and burrs. Chamfer

end of pipe, then clean tting socket and pipe joint area

of all dirt, grease, moisture or chips.

2. After checking pipe and socket for proper t, wipe socket

and pipe with cleaner-primer. Apply a liberal coat of

primer to inside surface of socket and outside of pipe.

DO NOT ALLOW PRIMER TO DRY BEFORE APPLYING

CEMENT.

3. Apply a thin coat of cement evenly in the socket. Quickly

apply a heavy coat of cement to the pipe end and insert

pipe into tting with a slight twisting movement until it

bottoms out.

4. Hold the pipe in the tting for 30 seconds to prevent

tapered socket from pushing the pipe out of the tting.

5. Wipe all excess cement from the joint with a rag. Allow

15 minutes before handling. Cure time varies according

to t, temperature and humidity.

NOTE:

Follow venting instructions carefully when

using PVC cement.

IMPORTANT:

All joints must be water tight. Flue condensate

is somewhat acidic, and leaks can cause

equipment damage.

Connection of the pipe and collar of the combustion air inlet

should just be a friction t. It is recommended that the inlet air

joint be sealed with RTV type sealant to allow the joint to be

separated for possible future service. The inlet and vent pipes

must be properly supported throughout the entire length.

▲

WARNING

CARBON MONOXIDE POISONING HAZARD

Do not replace any of the factory supplied venting

components with ﬁeld fabricated parts. Failure to

follow this safety warning exactly could result in

damaged vents, damaged components, carbon

monoxide poisoning, or death.

Connection of the vent pipe to the vent collar should also be

accomplished using RTV type sealant. This type sealant provides

a connection which remains exible and can be separated in the

future if service needs require the removal of the vent pipe for

service or clearance. See Figure 15.

Seal VENT PIPE

with RTV sealant

Seal INLET AIR PIPE

with RTV sealant

Front of Furnace

VENT AND INLET AIR CONNECTIONS

14 18-CD35D1-4

INSTALLER’S GUIDE

TABLE 7

PLASTIC PIPE DESIGNATIONS

PVC

ASTM STANDARD PIPE TYPE ALLOWABLE TEMPERATURE MARKING

F891 CELLULAR CORE *158 ASTM F891

D2665 DWV PIPE **158 ASTM D2665

D1785 SCH 40, 80, 120 **158 ASTM D1785

D2241 SDR SERIES **158 ASTM D2241

CPVC

ASTM STANDARD PIPE TYPE ALLOWABLE TEMPERATURE MARKING

D2846 CPVC 41 **212 ASTM D2846

F441 SCH 40, 80 **212 ASTM F441

F442 SDR SERIES **212 ASTM F442

ABS

ASTM STANDARD PIPE TYPE ALLOWABLE TEMPERATURE MARKING

D2661 SCH 40 DWV ***180 ASTM D2661

F628 SCH 40 DWV CELLULAR CORE ***180 ASTM F628

*Allowable temperatures based on classiﬁcations covered in ASTM D4396 [Deﬂection Temps Under Load (264 PSI)]

**Allowable temperatures based on classiﬁcations covered in ASTM D1784 [Deﬂection Temps Under Load (264 PSI)]

***Allowable temperatures based on classiﬁcations covered in ASTM D3965 [Deﬂection Temps Under Load (264 PSI)]

UPFLOW/ HORIZONTAL VENTING TABLE

MAXIMUM VENT LENGTH:

MODEL

DIRECT VENT (2 PIPE SYSTEM) -

MAXIMUM TOTAL EQUIVALENT FEET FOR

VENT AND INLET AIR PIPES (SEE NOTES)

NON-DIRECT VENT (1 PIPE SYSTEM) -

MAXIMUM TOTAL EQUIVALENT FEET FOR

VENT PIPES ONLY (SEE NOTES)

2" PIPE &

FITTINGS

2-1/2" PIPE

& FITTINGS

3" PIPE &

FITTINGS

4" PIPE &

FITTINGS

2" PIPE &

FITTINGS

2-1/2" PIPE

& FITTINGS

3" PIPE &

FITTINGS

4" PIPE &

FITTINGS

M951P040BU24AA 60 80 100 130 50 80 80 130

M951P060BU36AA 60 80 100 130 50 80 80 130

M951P080BU42AB 40 80 100 130 30 80 80 130

M951P100CU48AA NA NA 90 130 NA NA 70 130

M951P100DU60AA NA NA 90 130 NA NA 70 130

M951P120DU60AA NA NA 50 130 NA NA 30 130

NOTES: *First letter may be "A" or "T", NA = NOT ALLOWED

1. The INLET AIR of one pipe systems require the installation of a 90° elbow (to prevent dust and debris from falling straight into the furnace)

and a 2 foot horizontal or vertical straight pipe section connected before or after the elbow.

2. DO NOT MIX PIPE DIAMETERS IN THE SAME LENGTH OF PIPE OUTSIDE THE FURNACE CABINET (Except adapters at the top of the

furnace). If different inlet and vent pipe sizes are used, the vent pipe must adhere to the maximum length limit shown in the table above (See

Note 7 below for exception). The inlet pipe can be of a larger diameter, but never smaller than the vent pipe.

3. MAXIMUM PIPE LENGTHS MUST NOT BE EXCEEDED! THE LENGTH SHOWN IS NOT A COMBINED TOTAL, IT IS THE MAXIMUM

LENGTH OF EACH (Vent or Inlet air pipes in two pipe systems).

4. One standard radius 90° elbow is equivalent to 12' of 4" pipe; one SHORT radius 90° elbow is equivalent to 10' of 3" pipe and one LONG

radius elbow is equivalent to 6' of 3" pipe. One SHORT/LONG radius 90° elbow is equivalent to 7½' of 2½" pipe, and 5' of 2" pipe. Two 45°

elbows equal one 90°elbow.

5. The termination tee or bend must be included in the total number of elbows. If the BAYAIR30AVENTA termination kit is used, the equivalent

length of pipe is 5 feet. There is zero equivalent length for the BAYVENT200.

6. Pipe adapters are ﬁeld supplied.

7. 4" pipe may be reduced to 3" for termination with BAYAIR30AVENTA or BAYVENT200 without additional length restriction.

8. For Canadian applications Only: IPEX 196006 may be used for horizontal and vertical terminations. IPEX 081216, IPEX 081218, and IPEX

081219 may only be used for horizontal vent terminations. Equivalent lengths are IPEX 196009 = 5 feet, IPEX 081216 = 11 feet, IPEX 081218

= 16 feet, and IPEX 081219 = 21 feet.

TABLE 8

VENTING TABLES

18-CD35D1-4 15

INSTALLER’S GUIDE

DOWNFLOW/ HORIZONTAL VENTING TABLE

MAXIMUM VENT LENGTH:

MODEL

DIRECT VENT (2 PIPE SYSTEM) - MAXIMUM TOTAL

EQUIVALENT FEET FOR VENT AND INLET AIR PIPES

(SEE NOTES)

NON-DIRECT VENT (1 PIPE SYSTEM) - MAXIMUM

TOTAL EQUIVALENT FEET FOR VENT PIPES ONLY

(SEE NOTES)

2" PIPE &

FITTINGS

2-1/2" PIPE

& FITTINGS

3" PIPE &

FITTINGS

4" PIPE &

FITTINGS

2" PIPE &

FITTINGS

2-1/2" PIPE

& FITTINGS

3" PIPE &

FITTINGS

4" PIPE &

FITTINGS

M951P040BD24AA 60 80 100 130 50 80 80 130

M951P065BD42AA 45 80 100 130 40 80 80 130

M951P085CD48AA NA 80 100 130 NA 80 80 130

M951P110DD60AA NA 15 60 130 NA NA 50 130

NOTES: * - First letter may be "A" or "T", NA = NOT ALLOWABLE