Suburban P-40 User manual

INSTALLATION INSTRUCTIONS

FOR MODEL P-40

Design evaluated by CSA in accordance with Section 3280.707(a) (2) of HUD Manufactured Housing Construction

and Safety Standard for Energy E󰀩ciency.

This design is UL listed and meets UL 307B Standard for installation in recreational vehicles and mobile homes only.

This design is also certied by the Canadian Standard Association for installation in recreational vehicles only. In order

for the furnace to operate in conformity with generally accepted safety regulations, the installation instructions must be

followed. Failure to comply with the installation instructions will void the warranty on the furnace and any responsibility

on the part of AIRXCEL, INC. - SUBURBAN DIVISION.

The furnace was inspected before it left the factory. If any parts are found to be damaged, do not install the

furnace. Immediately contact the transportation company and le a claim.

This book contains instructions covering the operation and maintenance of your furnace. INSTALLER:

LEAVE THIS MANUAL WITH THE APPLIANCE. CONSUMER: RETAIN THIS MANUAL FOR FUTURE

REFERENCE. Should you require further information, contact your dealer or nearest Suburban Service

Center.

WARNING

Installation of this appliance must be made in

accordance with the written instructions provided

in this manual. No agent, representative or

employee of Suburban or other person has

the authority to change, modify or waive any

provision of the instructions contained in this

manual.

WARNING

FIRE, EXPLOSION AND

ASPHYXIATION HAZARD

Improper adjustment, alteration, service,

maintenance or installation can cause serious

injury or death.

Read and follow instructions and precautions

in User’s Information Manual provided with

this furnace. Installation and service must be

performed by a qualied service agency or the

gas supplier.

WARNING

Be sure the furnace and all ignition systems are

“OFF” during any type of refueling and while

vehicle is in motion or being towed.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow safety warning exactly

could result in serious injury, death or

property damage.

— Do not store or use gasoline or other

ammable vapors and liquids in the vicinity

of this or any other appliance.

— WHAT TO DO IF YOU SMELL GAS

• Evacuate all persons from the vehicle.

• Shut o󰀨 the gas supply at the gas

container or source.

• Do not touch any electrical switch, or

use any phone or radio in the vehicle.

• Do not start the vehicle’s engine or

electric generator.

• Contact the nearest gas supplier or

qualied service technician for repairs.

• If you cannot reach a gas supplier or

qualied service technician, contact

the nearest re department.

• Do not turn on the gas supply until the

gas leak(s) has been repaired.

— Installation and service must be

performed by a qualied installer, service

agency or the gas supplier.

676 Broadway Street

Dayton, Tennessee 37321

423-775-2131

www.AIRXCEL.com

PN: 205571

04-19-2018

WARNING

CARBON-MONOXIDE POISONING HAZARD

Failure to follow instructions could result

in severe personal injury or death due to

carbon-monoxide poisoning, if combustion

products inltrate into the building.

Check that all openings in the outside wall

around the vent (and air intake) pipe(s) are

sealed to prevent inltration of combustion

products into the building.

Check the furnace vent (and air intake)

terminal(s) are not obstructed in any way

during all seasons.

FOR YOUR SAFETY

DO NOT STORE OR USE GASOLINE OR

OTHER FLAMMABLE VAPORS AND LIQUIDS

IN THE VICINITY OF THIS OR ANY OTHER

APPLIANCE.

WARNING

Improper installation, adjustment, alteration,

service or maintenance can cause property

damage, personal injury or loss of life. Refer

to the installation instructions and/or owners

manual provided with this appliance. Installation

and service must be performed by a qualied

installer, service agency or the gas supplier.

INSTALLATION

INSTRUCTIONS

WARNING

Installation of this appliance must be made in

accordance with the written instructions provided

in this manual. No agent, representative or

employee of Suburban or other person has

the authority to change, modify or waive any

provision of the instructions contained in this

manual.

CAUTION

If possible, do not install the furnace to where the vent can be covered or

obstructed when any door on the trailer is opened. If this is not possible,

then the travel of the door must be restricted in order to provide a 6”

minimum clearance between the furnace vent and any door whenever

the door is opened.

NOTE: The exhaust temperature of this furnace could discolor or warp some

materials. You should verify that the material used on the coach door, panel, or cover

will not discolor or warp from the exhaust temperature whenever any door, panel, or

cover is in the open position.

CAUTION

Due to the di󰀨erences in vinyl siding, this appliance should not be installed

on vinyl siding without rst consulting with the manufacturer of the siding

or cutting the siding away from the area around the appliance vent.

In any installation in which the vent of this appliance can be covered

due to the construction of the RV or some special feature of the RV

such as slide out, pop-up etc. always insure that the appliance cannot

be operated by setting the thermostat to the positive “OFF” position and

shutting o󰀨 all electrical and gas supply to the appliance. Never operate

furnace with vent covered.

This furnace must be installed and vented as described in this

manual so that the negative pressure created by the air circulating

(return air) fan cannot a󰀨ect the combustion air intake or venting

of any other appliance. It is imperative that the products of

combustion be properly vented to the atmosphere and that all

combustion air supplied to burner be drawn from the outside

atmosphere. (See Installing Vent Assembly.)

IMPORTANT

If this furnace is to be connected to a common duct system also

serving a cooling unit, a manual or automatic damper is required

to prevent any cold conditioned air from circulating back into the

furnace. Cold air passing over the furnace combustion chamber

during the operation of the cooling unit can result in the formation

of condensation inside the furnace combustion chamber. This

condensation may promote corrosion and premature failure of

the combustion chamber.

NOTE: These furnaces shall be installed so the electrical components are protected

from water.

NOTE: Do not install the furnace with the vent facing toward the forward end of

the coach. See gures 8 and 9.

Please adhere strictly to the installation instructions to insure proper

installation and safe operation, as well as adequate clearances for accessibility.

This furnace is design certied for use with propane or conversion to natural gas.

Gas supply pressure for purposes of input adjustment:

GAS MINIMUM MAXIMUM

Propane 11.0” W.C.* 13.0” W.C.*

Natural Gas 5.0” W.C.* 7.0” W.C.*

*Water column

In the U.S.A., the installation of the furnace must be in accordance with local codes

and regulations. In the absence of local codes and regulations, installation must

comply with the latest edition of:

1. Standard for Recreational Vehicles NFPA 1192.

2. National Fuel Gas Code ANSI Z223.1/NFPA 54.

3. Furnace must be electrically grounded in accordance with the latest edition of

the National Electrical Code NFPA 70.

This unit is equipped with an electric igniter device that has an energy consumption

of .1 amp @24 volts A.C.

In Canada, the furnace must be installed in accordance with:

1. Standard CAN/CSA Z240.0.2-08 Recreational Vehicles.

2. CSA Standard CAN/CSA Z240.6.2-08/C22.2 No. 148-08 Electrical

Requirements for Recreational Vehicles.

3. Standard CAN/CSA Z240.4.2-08 Installation Requirements for Propane

Appliances and Equipment in Recreational Vehicles.

4. CAN/CGA B149 Installation Codes.

5. Any applicable local codes and regulations.

RETURN AIR

NOTE: Return air must be from within the living area of the coach.

NOTE: RV’s that have a wall of separation to a cargo area (Toy Box) to transport

internal combustion engine vehicles must not have return air opening from this area.

There are three methods described below for installing the furnace. Regardless of

the method you choose, we require that a permanent opening be provided in the

interior cabinetry of the coach directly in front of the furnace. The opening must allow

for free, unobstructed removal of the furnace. This opening may be used as a means

of providing circulating return air to the furnace. It is recommended that the opening

total 64 square inches. Suburban also recommends a return air opening of 49 square

inches be provided in the left side of coach cabinetry and centered by room air blower

opening. (See Figure 3.) These are suggested locations for return air. Other locations

and areas may be used. Regardless of the location for return air, the return air to the

furnace must total 113 square inches. (See Figure 3.)

It is important that adequate return air be provided to assure normal heating and

operation of the furnace. Failure to provide the minimum return air opening as well

as an adequate opening for furnace removal, voids the warranty.

A. INSTALLATION DIRECTLY AGAINST OUTER SKIN OF COACH

(See Figure 1)

MAXIMUM WALL THICKNESS FOR THIS TYPE INSTALLATION IS 2 1/4”

1. Locate the furnace near lengthwise center of the coach. Do not install the

furnace with the vent facing toward the forward end of the coach.

2. Choose a location for installation out of the way of wires, pipes, etc. which

might interfere with the installation. Adhere to the minimum clearances from

the cabinet to combustible constructions listed in Table 1. Refer to Figure 3 for

illustration of furnace clearances.

NOTE: Side and top clearances may be 0” for through the wall installations up to a

maximum wall thickness of 2 1/4”. (See Figure 1.)

3. When an appliance is installed directly on carpeting, tile or other combustible

material, other than wood ooring, the appliance shall be installed on a metal or

wood panel extending the full width and depth of the appliance. If preferred, the

carpeting, tile or combustible materials, other than wood may be cut away the

full length and depth of the appliance plus the appliance minimum clearances

to combustibles. (See Table 1.)

4. Cut an opening through the inner wall 12 7/16 x 13 1/8”. This will allow the rear

of the furnace to be installed against the outer skin of the coach. (See Figure 1.)

5. Cut two 3” diameter holes through the outer skin of coach as shown in Figure 1.

6. Put furnace in place, making sure that rear of furnace cabinet is as close to

outer skin of coach as possible and still assure proper vent tube overlap. (See

Installing Vent Assembly).

7. Secure furnace to the oor using the two (2) holes provided in furnace cabinet.

(See Figure 1.)

8. Install vent assembly. (See instructions for installing vent.)

Model Front Left

Side

Right

Side

Top Bottom Back Exhaust and

Intake Tube

P-40 1” 2” 2” 1” 0” 0” 3/8”

- NOTE - 0” MEANS TO SPACER BUMPS

CLEARANCE FROM DUCTS TO COMBUSTIBLE MATERIAL WITHIN

FIRST 3 FEET FROM FURNACE - 1/4” (See Figure 3)

TABLE 1

B. INSTALLATION DIRECTLY AGAINST INNER WALL OF COACH

(See Figure 2)

MAXIMUM WALL THICKNESS FOR THIS TYPE INSTALLATION IS 2 1/4”

1. Locate the furnace near lengthwise center of the coach. Do not install the

furnace with the vent facing toward the forward end of the coach.

2. Choose a location for installation out of the way of wires, pipes, etc. which

might interfere with the installation. Adhere to the minimum clearances from

the cabinet to combustible construction as listed in Table 1. Refer to Figure 3

for illustration of furnace clearances.

3. When an appliance is installed directly on carpeting, tile or other combustible

material, other than wood ooring, the appliance shall be installed on a metal or

wood panel extending the full width and depth of the appliance. If preferred, the

carpeting, tile or combustible materials, other than wood may be cut away the

full length and depth of the appliance plus the appliance minimum clearances

to combustibles. (See Table 1.)

4. Locate center lines for exhaust and intake tubes as shown in Figure 2. Cut two

3” diameter holes through coach wall for exhaust and intake. (See Figure 2.)

5. Put furnace in place, making sure that rear of furnace cabinet is as close to

inner wall of coach as possible and still assure proper vent tube overlap. (See

Installing Vent Assembly).

6. Secure furnace to the oor using the two (2) holes provided in the furnace

cabinet. (See Figure 1.)

7. Install vent assembly. (See instructions for installing vent.)

C. INSTALLATION USING VENT EXTENSION TUBES

When it is not possible to install the furnace as described in installations A or B,

extension tubes must be used to extend the exhaust and intake tube to the vent tube

assemblies on the outside of the coach. Avoid the use of extension tubes whenever

possible. If they must be used, it is important that the correct length tubes are used.

In order to determine the correct extension tube kit, you must determine the range in

which the extension falls. To do this, determine where the furnace is to be installed

and measure the distance from the end of the exhaust and intake tube to the outer

edge of the coach skin. This determines the extension tube range you need. Table 2

lists by kit number the vent extension range up to 9”.

Example: If the distance you measured is 2 7/8”, using Table 2 as your guide, you will

order Kit #520974 which accommodates a range from 2 1/4” to 3 1/8”. The extension

tube kit comes with complete installation instructions.

WARNING

Under no circumstances are the extension

tubes, as supplied by Suburban, to be cut,

altered, or modied in any way. To do so could

be dangerous and will void the responsibility of

AIRXCEL, INC. - SUBURBAN DIVISION.

EXTENSION TUBE

KIT NUMBER

MIN./MAX. LENGTH

(EXTENSION TUBE RANGE)

520974 2-1/4” to 3-1/8”

520975 3-1/8” to 4-7/8”

520595 4-7/8” to 7”

520596 7” to 9”

TABLE 2

INSTALLING VENT ASSEMBLY

The vent outlet must be installed so it is in the same atmospheric pressure zone as

the combustion air intake. The exhaust and intake tubes must be installed from the

outside, pass through the RV skin and slide onto the furnace exhaust and intake.

WARNING

Do not alter the vent assembly supplied with

this furnace. Any modications will result in

improper installation which could cause unsafe

furnace operation.

CAUTION

Combustion air must not be drawn from the living area. All air for

combustion must be drawn from the outside atmosphere. All exhaust

gases must be vented to the outside atmosphere - never inside the RV.

Therefore, it is essential to insure that the vent cap and tube assemblies

are properly installed.

1. Apply caulking to RV skin behind vent cap as shown in Figure 2. Apply caulking

generously around perimeter of vent cap and across center as shown.

2. Insert intake tube through RV skin and slide it onto the furnace intake (See

Figure 2.) Minimum tube overlap of 1/2” is required.

3. Insert the vent cap assembly with heat shield collar through the 3” diameter

hole in the RV skin as illustrated in Figure 2. Slide vent cap exhaust tube onto

furnace exhaust. Minimum tube overlap of 1 1/4” is required.

4. Attach vent cap assembly to outer skin of RV with the six (6) screws provided.

Do not install vent assembly upside down. The word “Suburban” must be right

side up.

CONNECTING GAS SUPPLY

Connect the gas supply to the furnace at the manifold. A suggested method is

illustrated in Figure 1. Other methods are acceptable if they allow for the gas to be

shut o󰀨 at the furnace for furnace removal while allowing other appliances to remain

operational.

NOTE: The compound used on threaded joints must be resistant to propane and

natural gas.

NOTE: The appliance and its individual shut-o󰀨 valve must be disconnected from the

gas supply piping system during any pressure testing of that system at test pressure

in access of 1/2 PSIG.

The appliance must be isolated from the gas supply piping by closing its individual

manual shut-o󰀨 valve during any pressure testing of the gas supply piping system at

test pressure equal to, or less than, 1/2 PSIG.

1. Be sure that the manual shut-o󰀨 valve is outside of the furnace jacket and

easily accessible. (See Figure 1.)

2. A drip leg should be installed upstream of the manual shut-o󰀨 valve exterior to

unit casing.

3. In order to maintain a check on gas supplied pressure to the furnace, Suburban

advises the installer to provide a 1/8” NPT plug tap for test gauge connection

immediately upstream of the gas supply connection to the furnace and that it

be readily accessible.

4. After the furnace has been connected to the gas supply, all joints must be

checked for leaks.

WARNING

Never check for leaks with an open ame. Turn

on the gas and apply soapy water to all joints to

see if bubbles are formed.

CONNECTING ELECTRICAL SUPPLY

This furnace is wired for 120 volts A.C. only. Connect the 120 volts A.C. wire leads in

the junction box located on the right side of the furnace cabinet.

All wiring and wire connections must conform to local codes and the latest edition of

the National Electrical Code NFPA 70.

CONNECTING DUCTS TO FURNACE

The following duct requirements must be followed in order to assure proper operation

of the furnace:

1. Maintain a minimum of 48 square inches open duct area throughout entire duct

system including through register. (Minimum 4 ducts 4” diameter.) Applicable

to under oor ducting as well.

NOTE: Ducts terminating in a dead air space (like holding tank compartments

or cargo areas (Toy Boxes) with no means for return air recirculation should

not be counted in the required duct area. Also, ducts 2” in diameter or smaller

should not be counted in the required duct area.

2. No outlet register is to be placed within 18” of the return air opening. Any

the return air opening. If a register is installed on a wall 90 degrees to the

return air, it can be less than 18”.

3. Make the duct connections at the furnace cabinet tight. Loose connections will

result in overheating of the component parts on the furnace and a reduction of

the heated air ow through the duct system.

4. Avoid making any sharp turns in the duct system. Sharp turns will increase the

static pressure in the plenum area and could cause the furnace to cycle.

5. Avoid making a lot of turns in the duct system. The straighter the duct system,

the better the performance of the furnace.

6. Maintain a minimum of 1/4” clearance where ducts pass through any

combustible construction; such as, coach cabinetry. (See Figure 3.)

NOTE: UL listed duct materials can be “0” clearance.

7. Do not install air boosters in the duct system. Such devices will cause the

furnace to cycle on limit and cause erratic sail switch operation.

NOTE: After installation of the furnace and duct system is completed, adjustments must

be made to obtain a temperature rise within the range specied on the Rating Plate.

INSTALLING THERMOSTAT

The thermostat used with this unit must have NO voltage output to return leg when

there is not a call for heat or in the “OFF” setting.

Locate the room thermostat approximately 4-1/2 feet above the oor on an inside

bulkhead where it is not a󰀨ected by heat from any source except room air. Connect

thermostat wiring to wires on right side of furnace marked “Thermostat Wires”. White

wire with red stripe is power wire to thermostat. (See wiring diagram.)

If your furnace is equipped with a thermostat that has an adjustable anticipator,

the anticipator should be set at .7 amps. If you desire linger heating cycles, adjust

the anticipator to a higher setting. If you desire shorter heating cycles, adjust the

anticipator to a lower setting. Adjustments to the anticipator setting should be made

in .5 amp increments.

PREVENTIVE MAINTENANCE

WARNING

If the user of this appliance fails to maintain it in

the condition in which it was shipped from the

factory or if the appliance is not used solely for its

intended purpose or if appliance is not maintained

in accordance with the instructions in this manual,

then the risk of a re and/or the production of

carbon monoxide exists which can cause personal

injury, property damage or loss of life.

CAUTION

Label all wires prior to disconnecting for servicing and servicing controls.

Wiring errors can cause improper and dangerous furnace operation. Proper

polarity MUST BE OBSERVED so the furnace motor will run with the proper

direction of rotation to insure correct air delivery. (See wiring diagram).

Always verify proper operation of furnace after servicing.

Your furnace should be inspected by a qualied service agency yearly before turning

the furnace on. Particular attention should be given to the following items.

1. Inspect furnace installation and vent termination to be sure furnace is properly

secured in place (see Installation Instructions), that vent terminates to the

atmosphere, and that vent tubes overlap properly (see Installing Vent Assembly.)

2. Inspect chamber and venting to assure that these components are physically

sound without holes or excessive corrosion and that the installation and/

or re-installation is in accordance with Suburban’s installation instructions.

(Reference installation manual supplied with furnace.)

WARNING

It is imperative that the products of combustion

be properly vented to atmosphere and that all

combustion air supplied to burner be drawn

from outside atmosphere.

3. Check the base on which furnace is mounted. Be sure it is physically sound,

void of any sagging, deterioration, etc.

4. Inspect furnace, the venting, ducting and gas piping to furnace for obvious

signs of deterioration. Correct any defects at once.

5. Inspect combustion chamber for restrictions in exhaust or intake. It is imperative

that the ow of intake combustion air and the ow of exhaust gases being

expelled to the outside atmosphere not be obstructed. Any soot or loose debris

should be blown out using compressed air. (See Figure 7.)

6. Inspect all gaskets. If any gaskets show signs of leakage or deterioration, replace

them. Safe operation of the furnace depends on all gaskets being tight.

7. Inspect return air inlet openings to the furnace. Remove any restrictions to

assure adequate air ow.

You, as the owner/user, should inspect the furnace monthly during the

heating season for presence of soot on vent. Operating the furnace under this

condition could lead to serious property damage, personal injury or loss of life.

If soot is observed on the vent, immediately shut the furnace down and contact

a qualied service agency.

Listed below are several safety related items that you should follow during the

heating season to assure continued safe operation of the furnace.

1. Inspect furnace venting. Venting must be free of obstructions, void of soot, and

properly terminated to the atmosphere. (See Installing Vent Assembly.)

WARNING

Do not install screens over the vent for any

reason. Screens will become restricted and

cause unsafe furnace operation. Accessories

are being marketed for RV products which we

do not recommend. For your safety, only factory

authorized parts are to be used on your furnace.

2. Periodically inspect the vent for obstructions or presence of soot. Soot is

formed whenever combustion is incomplete. This is your visual warning that

the furnace is operating in an unsafe manner. If soot is present, immediately

shut furnace down and contact your dealer or a qualied service person.

3. Periodically observe the main burner ame to assure it is burning with a hard

blue ame with well dened burner ports (See Figure 6). If ame appears

yellow or burner has a lazy ame, shut furnace down. It is possible that burner

needs cleaning or replaced. To inspect the main burner, remove the four (4)

screws (A, B, C and D) securing the burner access door to the combustion

chamber (See Figure 5). If excessive rust and corrosion are present on burner

surface, the burner must be thoroughly cleaned or replaced. The burner may

be cleaned using a steel wire brush and blown clean using high compression

air. Contact a qualied service person for assistance.

NOTE: To observe ame, cabinet front must be removed. Operation of burner can

then be observed through the viewing window on front of chamber (See Figure 5).

4. Keep furnace clean. More frequent cleaning may be required due to excessive

lint from carpeting, bedding material, etc. It is imperative that control

compartments, burners and circulating air passageways of the appliance be

kept clean.

5. The motor is permanently lubricated and requires no oiling.

6. Keep the furnace area clear of any combustible materials, gasoline or other

ammable vapor and liquids.

7. Before operating furnace, check the location of the furnace vent to make sure it

will not be blocked by the opening of any door on the trailer. If it can be blocked,

do not operate the furnace with the door open.

8. Do not restrict the ow of combustion air or the warm air circulation to the

furnace. To do so could cause personal injury and/or death.

9. Never operate the furnace if you smell gas. Do not assume that the smell

of gas in your RV is normal. Any time you detect the odor of gas, it is to

beconsidered life threatening and corrected immediately. Extinguish any open

ames including cigarettes and evacuate all persons from the vehicle. Shut

o󰀨 gas supply at Propane gas bottle. (See safety notice on front cover of this

manual.)

10. Immediately shut furnace down and call a service agency if furnace cycles

erratically or delays on ignition.

WARNING

Should overheating occur, or the gas supply

fail to shut o󰀨, shut o󰀨 the manual gas valve to

the appliance before shutting o󰀨 the electrical

supply.

11. Never attempt to repair damaged parts. Always have them replaced by a

qualied service agency.

12. Never attempt to repair the furnace yourself. Seek the help of a qualied

service person.

13. Never restrict the ducting installed by your trailer manufacturer. To do so could

cause improper furnace operation.

14. Do not install air boosters in the duct system. Such devices will cause the

furnace to cycle on limit and to have erratic sail switch operation.

15. Clothing or other ammable material should not be placed on or near the

appliance.

16. Always follow the Operating Instructions. Do not deviate from the step-by-step

procedures.

17. Do not use this appliance if any part has been submerged under water.

Immediately call a qualied service technician to inspect the appliance and

to replace any part of the control system and any gas control that has been

submerged under water.

18. When considering add-on rooms, porch or patio, attention must be given to the

venting of your furnace. For your safety, do not terminate furnace vent inside

add-on rooms, screen porch or onto patios. Doing so will result in products of

combustion being vented into the room or occupied areas.

19. In any installation in which the vent of this appliance can be covered due to

the construction of the RV or some special feature of the RV such as slide out,

pop-up etc. always insure that the appliance cannot be operated by setting the

thermostat to the positive “OFF” position and shutting o󰀨 all electrical and gas

supply to the appliance. Never operate furnace with vent covered.

OPERATING INSTRUCTIONS

WARNING

Do not operate furnace while vehicle is in motion

or being towed.

NOTE: During initial ring of this furnace a burn-o󰀨 of excess paint and oils remaining

from manufacturing process may cause “smoking” for 5 - 10 minutes.

1. Stop! Read Users Information Manual supplied with furnace.

2. Turn the manual valve or the valve at the outside Propane tank to the “OFF”

position. Do not force.

3. Set thermostat above room temperature to begin blower operation. A slight

delay will occur before the blower comes on. Allow blower to run for 5 minutes

for combustion chamber purge cycle. If blower does not come on or stops

before ignition cycle, go to shut down and contact your dealer or a local

recreational vehicle service agency.

4. After 5 minutes, move thermostat lever below room temperature. Blower will

remain on. Wait approximately 2 minutes for blower to go o󰀨.

5. Open manual shut-o󰀨 valve or the valve at the outside Propane tank. Correct

operating characteristics depend on the valve being positioned fully open.

Never attempt to operate with a valve partially closed.

6. Set thermostat lever to desired setting. If set above room temperature, blower

will come on.

7. Allow 30 seconds for main burner to light after blower comes on. This furnace

is equipped with an ignition device which automatically lights the burner. Do not

try to light the burner by hand.

8. If burner does not light, repeat Steps 1 through 8.

9. If after three (3) attempts with no ignition, go to shut down and contact your

dealer or a local recreational vehicle service agency. Do not continue to cycle

furnace through thermostat in an attempt to get ignition.

TO SHUT DOWN

1. Set the thermostat to lowest setting, then move lever to “OFF” position.

2. Turn o󰀨 all electric power to the appliance if service is to be performed.

3. Turn shut o󰀨 valve clockwise → to “OFF”. Do not force.

CONVERTING FROM PROPANE

TO NATURAL GAS

The furnace was factory equipped for use with Propane gas. For natural gas, use the

No. 30 drill orice provided with the furnace. (Orice is attached to furnace manifold

near valve.)

Gas supply (line pressure) for natural gas should be:

GAS MINIMUM MAXIMUM

Natural Gas 5.0” W.C.* 7.0” W.C.*

*Water column

CONVERTING FURNACE TO NATURAL GAS

1. Shut o󰀨 gas supply.

2. Disconnect gas supply and electrical power.

3. Remove outside vent assembly.

4. Remove chamber assembly from cabinet.

5. Remove manifold assembly.

6. Remove orice from manifold assembly.

7. Install the natural gas orice (No. 30 drill) supplied.

8. Convert valve to natural gas by removing regulator stem, turning over and

reinstalling. (Ring on stem will now show natural).

9. Reinstall manifold assembly.

10. Slide chamber assembly into cabinet and secure.

11. Reconnect vent assembly.

12. Reconnect gas and electrical connections.

13. Perform operations check and inspect for gas leaks.

NOTE: After completing the conversion, check the manifold (gas) pressure at the

pressure tap located on the outlet side of valve. Pressure should be 3.2” W.C

PARTS AND SERVICE

Contact a conveniently located recommended Suburban Service Center. Describe

to them the nature of your problem, make an appointment, if necessary, and provide

for delivery of your RV with the appliance installed.

To obtain information on locating a local service agency, contact:

AIRXCEL, Inc., - Suburban Division

Customer Service Department

676 Broadway Street

Dayton, TN 37321

(423) 775-2131 Ext. 7101

www.Airxcel.com

3 1/2

7 1/2

2 3/4

6 7/32

12 7/16

1/8

SUBURBAN

* 3.50" FROM CENTER LINE OF INTAKE TO

CENTER LINE OF EXHAUST

** 7.50" FROM CENTER LINE OF INTAKE TO FLOOR

HEAT SHIELD COLLAR

EXHAUST

AIR INTAKE

(2) 3.00" DIA. HOLES

INSIDE WALL

OUTSIDE SKIN

FLOOR

FURNACE

POWER SUPPLY

WIRES

THERMOSTAT WIRES

GAS LINE

SHUT-OFF VALVE

GAS LINE

ELBOW

ANCHOR TO FLOOR

MAXIMUM WALL THICKNESS 2.25"

NOTE: 0" CLEARANCE PERMISSIBLE

AT REAR OF FURNACE FOR

A WIDTH OF 2.25" MAXIMUM.

VENT CAP

Figure 1

Figure 2

Figure 3

SUBURBAN RECOMMENDS A RETURN AIR OPENING OF 49 SQ.

1N. MINIMUM (7" X 7") BE PROVIDED IN COACH CABINETRY

AND CENTERED BY ROOM AIR BLOWER OPENING ON LEFT

SIDE OF FURNACE WHEN USING ALL MINIMUM INSTALLATION

CLEARANCES.

SPACER BUMPS

MAINTAIN A 1/4 INCH CLEARANCE WHERE DUCTS

PASS THROUGH A CABINET WALL WITHIN FIRST (3)

FEET FROM FURNACE. UL LISTED DUCT MATERIALS

CAN BE 0" CLEARANCE.

FURNACE

SPACER BUMPS

SUBURBAN RECOMMENDS THAT A 64 SQ. IN. MINIMUM OPENING

FOR RETURN AIR IN FRONT OF THE FURNACE (8" X 8" OPENING)

BE PROVIDED.

INTAKE TUBE

2 1/4"

2 3/4"

MAX.

*7"

EXHAUST TUBE

7 1/2"

3 1/2" MAXIMUM WALL THICKNESS FOR THIS

TYPE INSTALLATION IS

2 1/4"

3 1/2"

HEAT SHIELD COLLAR

WARNING:

COLLAR MUST BE ATTACHED

TO ASSURE SAFE

OPERATION. DO NOT

REMOVE COLLAR.

VENT CAP

CENTERLINE OF FURNACE

INSTALLATION

3" DIA. (2) HOLES

(OUTER SKIN)

3 1/2" X 7" CUTOUT

THRU COMBUSTIBLE

CONSTRUCTION *

CAULK BEHIND VENT CAP AS

SHOWN TO SEAL BETWEEN

EXHAUST AND INTAKE AND TO

PREVENT MOISTURE INSIDE

FURNACE COMPARTMENT. APPLY

CAULKING GENEROUSLY AROUND

PERIMETER OF VENT CAP AND

ACROSS CENTER AS SHOWN.

CENTER PUTTY STRIP IS

ESSENTIAL.

CODE

BLACK

GREEN

BROWN

WHITE

RED

YELLOW

BLUE

COLOR

16/30 TGS 150°C 18 AWG WIRE

NO. 18 250° RADIX WIRE UL-3257

340545

TRANSFORMER

THERMOSTAT

LIMIT

SWITCH

N.C.

MOTOR

MODULE

BOARD

ELECTRODE

BK G W

DISCONNECT

BLOCK

BR GROUNDING

TERMINAL

SAIL

SWITCH

N.O.

BK VALVE

REDUNDANT

ELECTRODE

MODULE

BOARD

LIMIT

SWITCH

N.C.

SAIL

SWITCH

N.O.

MOT

TRANSFORMER

THERMOSTAT

SWITCH

N.O.

115 V.A.C.

24 V.A.C.

W/R

SPARK

SENSOR

FLAME

115 V.A.C.

VALVE

W/R

MODULE BD.

RELAY SWITCH

IND

24V

CAPACITOR

BR BR

G / Y

P-40

CAPACITOR

W/R

WHITE

WITH RED

STRIPE

* THERMOSTAT POWER WIRE

ALL WIRES ARE 18 AWG UNLESS OTHERWISE SPECIFIED.

NOTE: IF ANY OF THE ORIGINAL WIRES AS SUPPLIED

WITH THE APPLIANCE MUST BE REPLACED, IT MUST BE

REPLACED WITH WIRING MATERIAL HAVING A

TEMPERATURE RATING OF AT LEAST 105°C.

Figure 4

Figure 6

CORRECT FLAME INCORRECT FLAME

SHARP BLUE FLAME

YELLOW FLAME

FLAMME CORRECTE FLAMME INCORRECTE

FLAMME AIGUE BLEUE FLAMME JAUNE

NT-30SP • NT-34SP • NT-40 • P-40 • P-40B

+ +

++A B

BURNER ACCESS DOOR

COMBUSTION CHAMBER

CABINET

BURNER OBSERVATION

WINDOW

Figure 5

Figure 7

TO CLEAN THE CHAMBER, THE FURNACE MUST BE

REMOVED FROM THE CABINET AND THE MANIFOLD,

BLOWER ASSEMBLY AND CONTROLS REMOVED LEAVING

TH CHAMBER

ONLY, AS SHOWN. USING COMPRESSED AIR,

BLOW THROUGH THE CHAMBER, AS SHOWN BY ARROWS,

TO REMOVE SOOT OR LOOSE DEBRIS.

Figure 8

INCORRECT

CORRECT

Figure 9

TWO YEAR LIMITED WARRANTY

SUBURBAN RECREATIONAL VEHICLE FURNACE

TWO YEAR LIMITED WARRANTY

This Suburban product is warranted to the original purchaser to be free from defects in material and workmanship under normal use and maintenance for a period of two years

from date of purchase whether or not actual use begins on that date. It is the responsibility of the consumer/owner to establish the warranty period. Suburban does not use

warranty registration cards for its standard warranty. You are required to furnish proof of purchase date through a Bill of Sale or other payment records.

Suburban will replace any parts that are found defective within the rst two years and will pay a warranty service allowance directly to the recommended Suburban Service

Center at rates mutually agreed upon between Suburban and its recommended service centers. Replacement parts will be shipped FOB the shipping point within the

Continental United States, Alaska and Canada to the recommended service center performing such repairs. All freight, shipping and delivery cost shall be the responsibility

of the owner. The exchanged part or unit will be warranted for only the unexpired portion of the original warranty. Before having warranty repairs made, conrm that the

service agency is a recommended service center for Suburban. DO NOT PAY THE SERVICE AGENCY FOR WARRANTY REPAIRS; SUCH PAYMENTS WILL NOT BE

REIMBURSED.

Suburban reserves the right to examine the alleged defect in the furnace or component parts, and it is the owner’s obligation to return the furnace and/or component parts

to Suburban or its representative. When returning a furnace, it must include all component parts and the serial number plate. Returned component parts must be individually

tagged and identied with the furnace’s model number, serial number and date of installation.

For warranty service, the owner/user should contact the nearest recommended Suburban Service Center, advising them of the model and serial numbers (located on the

furnace) and the nature of the defect. Transportation of the RV to and from the Service Center and/or travel expenses of the Service Center to your location is the responsibility

of the owner/user. A current listing of recommended service centers may be obtained from Suburban’s website, www.AIRXCEL.com. If you cannot locate a recommended

service center locally, the service agency chosen to perform warranty repairs must contact our Service Department at 423-775-2131 for authorization before making repairs.

Unauthorized repairs made will not be paid by Suburban.

THREE YEAR LIMITED WARRANTY ON HEAT EXCHANGER

The furnace heat exchanger is further warranted to be free from defects in material and workmanship during the third through fth year after the date of original purchase. A

replacement heat exchanger will be provided under the same conditions as stated in the two year warranty EXCEPT no labor reimbursement will be provided.

LIMITATION OF WARRANTIES

ALL IMPLIED WARRANTIES (INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY) ARE HEREBY LIMITED IN DURATION TO THE PERIOD FOR WHICH EACH

LIMITED WARRANTY IS GIVEN. SOME STATES DO NOT ALLOW LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS SO THE ABOVE LIMITATIONS MAY

NOT APPLY TO YOU. THE EXPRESSED WARRANTIES MADE IN THIS WARRANTY ARE EXCLUSIVE AND MAY NOT BE ALTERED, ENLARGED, OR CHANGED BY

ANY DISTRIBUTOR, DEALER OR OTHER PERSON WHOMSOEVER.

SUBURBAN WILL NOT BE RESPONSIBLE FOR:

1. Normal maintenance as outlined in the installation, operating and service instructions owner’s manual including cleaning of component parts; such as, orices and

burners.

2. Initial checkouts and subsequent checkouts which indicate the furnace is operating properly, or diagnosis without repair.

3. Damage or repairs required as a consequence of faulty or incorrect installation or application not in conformance with Suburban instructions.

4. Failure to start and/or operate due to loose or disconnected wires; water or dirt in controls, fuel lines and gas tanks; restriction or alteration of return air circulation; low

voltage.

5. Routine adjustments that may be required to the thermostat, electrode and burner.

6. Costs incurred in gaining access to the furnace.

7. Parts or accessories not supplied by Suburban.

8. Freight charges incurred from parts replacements.

9. Damage or repairs needed as a consequence of any misapplication, abuse, unreasonable use, unauthorized alteration, improper service, improper operation or failure

to provide reasonable and necessary maintenance.

10. Suburban products whose serial number has been altered, defaced or removed.

11. Suburban products installed or warranty claims originating outside the Continental U.S.A., Alaska, Hawaii and Canada.

12. Damage as a result of oods, winds, lightning, accidents, corrosive atmosphere or other conditions beyond the control of Suburban.

13. ANY SPECIAL, INDIRECT OR CONSEQUENTIAL PROPERTY, ECONOMIC OR COMMERCIAL DAMAGE OF ANY NATURE WHATSOEVER.

Some states do not allow the exclusion of incidental or consequential damages, so the above limitation may not apply to you.

NO REPRESENTATIVE, DEALER, RECOMMENDED SERVICE CENTER OR OTHER PERSON IS AUTHORIZED TO ASSUME FOR SUBURBAN MANUFACTURING

COMPANY ANY ADDITIONAL, DIFFERENT OR OTHER LIABILITY IN CONNECTION WITH THE SALE OF THIS SUBURBAN PRODUCT.

This warranty gives you specic legal rights, and you may also have other rights which vary from state to state.

IF YOU HAVE A PRODUCT PROBLEM

FIRST:

If your RV has its original furnace and is still under the RV manufacturer’s warranty, follow the steps suggested by your dealer or manufacturer of the RV.

SECOND:

Contact a conveniently located recommended Suburban Service Center. Describe to them the nature of your problem, make an appointment, if necessary, and provide for

delivery of your RV to the selected service center.

THIRD: