Atwood 8940 Iii Dclp Troubleshooting

LITERATURE NUMBER MPD 31232

hydro flameTM

8900-III-LD Series Furnace

Atwood Mobile Products 8940 Furnace User Manual. DCLP-III DCLP-III ACLC-III ACLC-III. BTU Input 35,000 40,000 35,000 40,000. Output BTU/HR 27,300. We have an 8940-III-dclp furnace serial #(NNN) NNN-NNNNwith a new atwood dsi board and the furnace will light, run about 5 seconds, shut down retry 2 more times and flash a 3 red light code. Based on read more. Atwood Mobile Products HYDRO FLAME 8940, HYDRO FLAME 8935 User Manual. LITERATURE NUMBER MPD 31232. 8900-III-LD Series Furnace. MODELS 8935, 8940. Technical Installation Manual. ENGLISH, FRANCAIS (et Canada). DCLP-III DCLP-III. Atwood Mobile Products HYDRO FLAME 8940, HYDRO FLAME 8935 User Manual. LITERATURE NUMBER MPD 31232. DCLP-III DCLP-III.

MODELS 8935, 8940

Technical Installation Manual

ENGLISH, FRANCAIS (et Canada)

THIS INSTRUCTION MANUAL IS FOR USE BY AN AUTHORIZED SERVICE TECHNICIAN TO INSTALL AN ATWOOD - hydro flameTM FURNACE.

INSTALLER: LEAVE THIS MANUAL WITH APPLIANCE. CONSUMER: RETAIN THESE MANUAL FOR FURTHER

REFERENCE.

This furnace design has been certified for installation in recreation vehicles as a MSP Category III furnace. Follow this installation instruction to insure safe operation of the furnace. Failure to install furnace according to this installation instruction nullifies the furnace warranty.

SAFETY ALERT SYMBOLS

Iii

Safety Symbols alerting you to potential personal safety hazards. Obey all safety messages following these symbols.

WARNING

CAUTION

avoid possible

avoid possible

injury or death

injury and/or property damage

WARNING: If the information in this manual is not followed exactly, a fire or explosion may result causing property damage, personal injury or loss of life.

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

Evacuate all persons from vehicle.

Shut off gas supply at gas container or source.

Do not touch any electrical switch, or use any phone or radio in vehicle.

Do not start vehicle’s engine or electric generator.

Contact nearest gas supplier or qualified Service Technician for repairs.

If you cannot reach a gas supplier or qualified Service Technician, contact the nearest fire department.

Do not turn on gas supply until gas leak(s) has been repaired.

Installation and service must be performed by a qualified Service Technician, Service Center or gas supplier.

•Installation

Effective 3/08

INDEX

FURNACE SPECIFICATIONS ..............................................................

1

DIMENSIONS ..................................................................

1

WEIGHT ........................................................................

1

MINIMUM CLEARANCE TO FLOORBOARDS, WALLS,

& SIMILAR COMBUSTIBLE BUILDING MATERIALS..................................

2

SAFETY INFORMATION..................................................................

1-2

FURNACE INSTALLATION ..................................................................

2

VENT INSTALLATION - HORIZONTAL & VERTICAL ......................................

2

WALL CUTOUT HORIZONTAL & VERTICAL ..............................................

2-3

DUCTING HORIZONTAL & VERTICAL ......................................................

3

Flexible Ducting ......................................................................

3

Hard Ducting ........................................................................

3

OPTIONAL INSTALLATION - BOTTOM DISCHARGE KIT..................................

3

GAS CONNECTION ........................................................................

3

ELECTRICAL CONNECTIONS ..........................................................

3-4

Conductor Sizing Table ............................................................

3

12 volt DC Models ..................................................................

3

120 volt AC Models ..............................................................

3-4

Thermostat ..........................................................................

4

CONVERTIBLE GAS CONTROL ............................................................

4

Valve Conversion ....................................................................

4

Orifice Replacement ................................................................

4

SYSTEM CHECK TESTS ....................................................................

4

PROPANE GAS PRESSURE ..............................................................

4

STATIC PRESSURE ........................................................................

5

AC & DC WIRING DIAGRAMS ............................................................

5

ILLUSTRATIONS ............................................................................

6

REPLACEMENT PARTS LIST & DRAWING ..............................................

7

SPECIFICATIONS

*(W.C. = Water Column)

MODEL #

8935

8940

8935

8940

DCLP-III

DCLP-III

ACLC-III

ACLC-III

BTU Input

35,000

40,000

35,000

40,000

Output BTU/HR

27,300

31,200

27,300

31,200

Type Gas

LP

LP

LP/NAT

LP/NAT

Duct Static Pressure -

.10˝ W.C.*

.10˝ W.C.*

.10˝ W.C.*

.10˝ W.C.*

Power Supply (VOLTS)

12-DC

12-DC

120-AC

120-AC

Watts - WITH OUT DOOR

151

151

360

360

Amperage

12.6

12.6

3

3

MINIMUM RETURN AIR

80 in2

80 in2

80 in2

80 in2

DIMENSIONS

WEIGHT

ALL MODELS WITH DOOR

WIDTH

HEIGHT

DEPTH

Casing

16-1/2˝

9-1/8˝

23-1/2˝ - 26˝

FURNACE

38 lbs.

Vent

5-3/8˝

SHIPPING

45 lbs.

MINIMUM CLEARANCE TO

FLOORBOARDS, WALLS & SIMILAR COMBUSTIBLE BUILDING MATERIALS*

MUST BE PROVIDED THE FULL LENGTH AND WIDTH OF UNIT

HORIZONTAL

TOP ----

1/2˝

BOTTOM

3/16˝

SIDES ----

REAR --

1/2˝

VERTICAL

TOP ----

1/2˝

BOTTOM

----0˝

SIDES ----

REAR --

1/2˝

Spacing of 1/4˝ to ducting within 3 feet of furnace must be provided unless UL listed wire bound vinyl ducts are used. All ducting material should be rated for continuous use at 200˚F.

NOTE: Clearances are specifically for plywood or similar building materials surrounding furnace (i.e. furnace should NOT be located under furniture or in a closet space where clothing or other material could be located.)

NOTE: Efficiency rating is a thermal rating determined under continuous operating conditions, independent of any installation. Efficiency rate is given at 77% minimum, actual efficiency rating may be higher.

WARNING

CARBON MONOXIDE POISONING

Furnace must be installed and vented to these instructions.

Improper installation, adjustment, alteration, service or maintenance can cause injury or property damage.

Improper installation location may cause furnace to produce negative pressure, affecting combustion air or venting of other appliances.

CRITICAL INSTALLATION WARNINGS

DO NOT install furnace on material that restricts return air, like carpet or any soft material such as vinyl.

DO NOT install furnace where clearance to combustibles cannot be maintained.

DO NOT modify furnace in any way.

DO NOT alter furnace for a positive grounding system.

Atwood 8940 Iii Dclp Troubleshooting

DO NOT HI-POT furnace unless electronic ignition system (circuit board) has been disconnected.

DO NOT use battery charger to supply power to DC model furnace even when testing.

DO NOT use 120 volt AC current with DC models.

DO NOT use furnace cabinet area as a storage compartment.

DO NOT vent furnace with venting system serving another appliance.

DO NOT vent furnace to an outside enclosed porch area.

DO NOT use for temporary heating of buildings or structures under construction.

Protect building materials from degrading from flue gas exhaust.

Protect furnace electrical components from water.USA AND CANADA -

FOLLOW ALL APPLICABLE STATE AND LOCAL CODES -

IN THE ABSENCE OF LOCAL CODES OR REGULATIONS, REFER TO CURRENT STANDARDS OF:

Recreation Vehicles ANSI A119.2/NFPA 501C.

National Fuel Gas Code ANSI Z223.1 and/or CAN/CGA B149 Installation Codes

Federal Mobile Home Construction & Safety Standard, Title 24 CFR, part 3280, or when this Standard is not applicable, the Standard for Manufactured Home Installations (Manufactured Home Sites, Communities and Set-Ups), ANSI A255.1 and/or CAN/CSA-Z240 MH Series, Mobile Homes.

Ground - National Electrical Code ANSI/NFPA No. 70 and/or CSA C22.1

Park Trailers ANSI 119.5

NOTE: The direct high voltage spark ignition generates a radio frequency that could cause interference with other microprocessor based equipment. Locate equipment at least five feet (5’) from furnace location. If this distance cannot be maintained, purchase MPD 37773 (a shielded high voltage lead).

WARNING

CARBON MONOXIDE POISONING

Properly seal vent assembly to prevent carbon monoxide from entering coach.

DO NOT draw combustion air from living area. DO NOT vent exhaust air into the living area or an enclosed porch.

Return air is supplied through openings in furnace casing. All return air passages must be kept clear for furnace to function properly. Refer to

MINIMUM CLEARANCE TO FLOORBOARDS, WALLS & SIMILAR COMBUSTIBLE BUILDING

MATERIAL. The total unobstructed return air opening size(s) must NOT BE LESS than specified in SPECIFICATIONS-MINIMUM RETURN AIR. Failure to meet minimum return air requirements nullifies furnace warranty.

STANDARD FURNACE INSTALLATION

General Installation - LOCATION

Install furnace through an exterior wall.

DO NOT install furnace near tilt-out rooms, slide-outs, doors or other projections that could obstruct furnace exhaust.

Locate furnace near midpoint of coach for single furnace applications.

Installation must provide accessibility if any repairs are necessary to the furnace. Failure to meet this requirement will create additional labor costs that will be the responsibility of the installer.

DO NOT install vent in areas where projections or door openings come within 6˝ of vent tube opening.

DO NOT install furnace in an area where wires, pipes, or other objects will interfere with the installation or operation of furnace.

DO NOT directly install furnace on material that restricts return air, such as directly on carpet, or soft material (like vinyl).

If you must install furnace on carpet or soft material, install furnace on cleats, or on a wood or metal panel extending the full width and depth of furnace plus minimum clearances to combustibles.

DO NOT use petroleum or citrus type cleaners on plastic parts, as damage may occur.

The furnace must always be installed level (front to back, side to side) to prevent water intrusion into the interior.

Atwood Model 8940-iii-dclp Parts

WALL CUTOUT OPTIONS

RECOMMENDED WALL THICKNESS 0˝ to 2-1/2˝

Do not oversize hole - oversizing can result in water leakage.

EXTERIOR WALL CUTOUT (FIG 1)

A

B

C

HORIZONTAL & VERTICAL

3-1/8˝

2-3/8˝

3-1/2˝DIA HOLE

VENT INSTALLATION (FIG 1)

HORIZONTAL & VERTICAL INSTALLATION

1.Locate vent hole cutout as called out in (FIG 1).

2.Drill 3-1/2˝ diameter hole through side wall of coach.

3.Remove vent and vent ring from furnace.

4.Insert furnace from backside of wall. Line up hole in wall and furnace.

5.Apply sealant to back of vent ring and vent cap base.

6.Install vent assembly with HOT at top for horizontal and on right side for vertical installation (FIG 1-1A). Slip vent into combustion air intake tube. Secure to wall with four (4) screws.

7.Vent must have a minimum 1-1/4” over lap on exhaust tube and a minimum 1/2˝ overlap on combustion airtube.

8.Horizontal units - secure to floor with two (2) screws through legs on back of casing. Vertical units use vertical mounting brackets and self-tapping screws to hold furnace to floor (tabs on control box can be used also to secure furnace).

DUCTING - HORIZONTAL & VERTICAL (FIG 3-4A)

HORIZONTAL

PROPER DUCT INSTALLATION IS CRITICAL TO THE OPERATION OF THIS FURNACE

CONTINUOUS USE MATERIALS RATING

DUCTS IN LENGTH OR MORE

200˚F.

DUCTS LESS THAN 9˝ IN LENGTH

250˚F.

METAL BOOTS LESS THAN IN LENGTH

250˚F.

Ducting systems can include any combination of discharge openings, as long as static pressure and minimum discharge area requirements are met.

ALL MODELS - (also see STATIC PRESSURE TEST)

48 IN2

REQUIRED MINIMUM DISCHARGE

REQUIRED MINIMUM RETURN AIR

80 IN2

• See MINIMUM CLEARANCE TO FLOORBOARDS, WALLS & SIMILAR COMBUSTIBLE BUILDING MATERIALS.

Each 4-inch duct opening provides 12 in2 of discharge area. Provide an extra 12 in2 of non closeable duct discharge area for each closeable register used.

Use of 2˝ ducts does not count toward achieving min. discharge req. Ducting in dead air space with no return air, such as holding tank areas, does not count toward achieving min. discharge requirements.

Adjust ducting installation to obtain air rise of 100˚F - 130˚F.

Flexible Ducting System

When designing Flexible Duct Systems:

avoid sharp bends or crushed ducts

stretch all ducts and run them directly to outlets, keeping quantity and angles of bends to a minimum

1.Remove knockout plates from desired outlets.

2.Attach duct adapter to each opening, by inserting flange over casing, locking tab into casing slot and turning adapter 90˚.

3.Attach and secure FOUR-INCHflexible ducts to adapters.

4.Run ducts to desired location within RV, secure to registers.

5.Additional ducting may be needed to maintain static pressure.

Hard Ducting Floor System

When designing Hard Duct Systems:

undersize ducting will cause high temperature limiting

oversize ducting will cause inadequate air flow from registers

when hard ducting is 1-1/2˝ in depth, an additional flex duct may be needed to maintain installation static requirements

DO NOT install floor registers within 2 feet of return air openings.

OPTIONAL INSTALLATION - BOTTOM DISCHARGE (FIG 4-4)

1.Remove bottom discharge cover plate. This ducting option must be connected to a ducting system. FIG 3 (parts breakdown) #40 - GASKET AND PLENUM PLATE KIT is available when attaching furnace.

2. If cutout is required:

FLOOR CUTOUT

BOTTOM DISCHARGE

A

B

C

D

HORIZONTAL-WITHOUT DOOR (FIG 4)

18-20 1/2˝

5-1/2˝

10-1/2˝

3/4˝

3.Fasten plenum plate (4-E) over floor cutout. If a gasket and plenum plate are not used, seal furnace to hard duct system making sure seal is air-tight, continue with STEP 5.

4.Position gasket (4-F) on plenum plate.

5.Set furnace on gasket, gasket must remains in position.

Use additional ducting to maintain correct static pressure.

VERTICAL

The only ducting option, when using vertical installation, are the top two ducts and tw ducts off the back of the casing. This is the only configuration allowed with vertical installation (FIG 3A).

GAS CONNECTION

1.Connect gas line to fitting on top rear of furnace. Be sure all male pipe threads, other than flare fittings, are treated with a sealing compound resistant to the action of propane (LP) gas. DO NOT put sealing compound on flare fittings.

2.A 3/8˝ flared fitting connection is provided for supply connection to furnace. The gas supply line of the furnace must be of adequate size to provide 11˝ W.C. gas pressure. This pressure must be maintained under maximum flow conditions with all gas appliances in operation.

3.Use two wrenches to hold fitting and flare nut when tightening gas line to fitting. (FIG. 2)

ELECTRICAL CONNECTION (FIG 5)

WARNING

INJURY OR PROPERTY DAMAGE

Label all wires before disconnecting for service. Wiring errors can cause improper and dangerous operation.

Atwood 8940 Iii Dclp Troubleshooting Manual

Verify proper operation after servicing.

Disconnect electrical power before servicing.

Conductor Sizing Table - MAX. 10% VOLTAGE DROP - (12 VDC)

CURRENT DRAW (AMPS)

8

9

10

15

20

GAGE

MAX. LENGTH OF SAE CONDUCTOR (IN FEET) FROM SOURCE TO DEVICE

18

21

19

17

11

9

16

33

29

26

17

13

14

52

46

41

28

21

CAUTION

PROPERTY DAMAGE

This connection is for low-voltage battery or direct current only. Do not connect to 120or 240volts AC.

This unit is designed for negative ground 12 volt DC ONLY. Polarity must be observed so furnace motor will run in proper rotation. DO NOT attempt to alter to a positive ground system.

12 VOLT DC MODELS

Route 12 volt DC and thermostat leads to left side of control box. Use a minimum of 18 GA wire to minimize voltage drop. The furnace must be installed so electrical components are protected from water. To make electrical connections: see WIRING DIAGRAM FIG 5

1.Route wiring to left side of furnace.

2.Connect red wire to positive side of power supply.

3.Connect yellow wire to grounded side of power supply.

4.Connect blue wire marked positive thermostat to + side wire of thermostat using 22-18 GA stranded wire.

5.Connect the other blue wire to the other thermostat lead using minimum 22-18 GA stranded wire.

See instruction with thermostat for complete wiring directions.

For best furnace performance when power supply is from a converter equipped with a charging port, wire the converter to furnace parallel with battery. This provides consistent voltage to furnace, increasing component life, filtering power surges and AC spikes

120 VOLT AC MODELS

Route 120 volt AC and thermostat leads to wires located on the left side of control box using a minimum of 18 GA wire. The furnace must be installed so electrical components are protected from water. To make electrical connections see WIRING DIAGRAM FIG 5.