RV Products 8535 SERIES Manuel de service

1September 2003INTRODUCTIONThe 2004 edition of the Atwood Furnace Service Manual is a resource created to helpservice technicians identify Atwood prod

10IMPORTANT: If any original wire has to be replaced, it must be replaced with type 105° C or its equivalent.Terminal Block on 85 Models only.REDBLACK

1185 Series Wiring DiagramsRedRelayRedBlueRedBlackYellowHigh Tension+12V DCNeg.RedYellowElectrodeYellowBlackValveRed123456123456+ ThermoThermoMotorCir

12Wiring Diagram for 8900-IIIDC Wiring Diagram+12 VDC redCircuit breakerON/OFF Switch+Thermo blue-12 VDC yellowThermo blueredyellowbluemotorrelayredbl

13WIRING DIAGRAM FOR 2-STAGE FURNACETwo Stage FurnaceModels 1522 & 2334WITH DOOR AND WITHOUT DOORTwo Stage FurnaceModel 2540WITH DOOR AND WITHOUT

14ENGLISH, FRANCAIS (et Canada) •Installation •OperationEffective 6/19/02MPD 38285hydro flameTMModel 1H2CDigital ThermostatFOR STANDARD FURNACES&

15ENGLISH, FRANCAIS (et Canada) •Installation •OperationEffective 2/4/02LITERATURE NUMBERMPD 38914hydro flameTMModel 2H2CTwo Stage FurnaceDigital The

16Sequence of Operation - DC Models (STANDARD ONE-STAGE)The ON/OFF switch allows power to pass to the circuitbreaker and the thermostat.The thermosta

17The digital thermostat controls the operating circuit to the furnace byreacting to room temperature. When the room temperature is below thethermosta

18Sequence of OperationPilot ModelsThe thermostat controls the operating circuit to thefurnace by reacting to room temperature to open andclose a set

19Sequence of Operation - AC ModelsOperating Circuitry 24 VACThe transformer receives 120 VAC which it converts to24 VAC for the operating circuitry.

2Recommended Tools and EquipmentU-Tube Manometer - P/N 34706 - This is the most accurate device for measuring gas pressure. If you use adial-type mano

20 WARNINGCRITICAL INSTALLATION CRITERIA• Do not install the furnace on material that restricts return air, such as carpet, or any softmaterial, such

21ANNUAL PREVENTATIVE MAINTENANCE INSPECTIONThe following preventive maintenance and safety checks should be performed by a qualified RV technicianonc

22Mechanical ThermostatWHAT IS A THERMOSTAT?• It is an ON/OFF switch controlled by a bi-metal coil which opens and closes an electrical contact bysens

23CATALOG # ON BOARD ORDER-SERVICE PART NUMBER05-159007-103...FENWAL, old style, uncovered, 12VDC3671605-309017-153...FENWAL, uncovered, no

24RelaySail SwitchLimit Switch85-II, 89-IPart # 351321/4˝ terminals85-III, 85-IV, 1522, 2334Part # 37022 (was 36176)1/4˝ terminals79-II, 89-II, 89-III

25Dual Solenoid Gas ValveBurner Head, Electrode and Valve AssemblyPower from Ignition ControlShut off power before servicing (red wire)+12VDC-12VDCLoc

2620 lb. Bottle (*30 lb. bottle multiply X 1.40)% Full +20° 0° -5° -10° -15°60% 36,000 18,000 12,750 8,500 4,25050% 32,400 16,200 12,150 8,100 4,05040

27#2 - VoltageSee 4 Always previous page.#3 - Minimum Ducting RequirementsThe various BTU sizes of 85, 89 and 2-stage series furnaces require a minimu

28NOTESNOTESTHIS PAGE INTENTIONALLY LEFT BLANK

29Guides are only intended for use on Atwood®products by service technicians who have successfully completedAtwood®training. This guide should be used

3hydro flame™ FURNACES TABLE OF CONTENTSRecommended Tools & Equipment ...

3030*indicates NOT covered under warranty.Guides are only intended for use on Atwood®products by service technicians who have successfully completedAt

31FURNACE - ELECTRONIC IGNITION Model (continued) Effective: 8/10/98CAUSE SOLUTIONSOOTING (caused by lazy yellow flame)Low gas pressure-------------

3232*indicates NOT covered under warranty.Guides are only intended for use on Atwood®products by service technicians who have successfully completedAt

33FURNACE - Pilot Model (continued) Effective: 8/10/98CAUSE SOLUTIONBLOWER SHUTS OFF AT SAME TIME BURNER SHUTS OFFFaulty relay----------------------

34Terminology DefinitionAC Motor A Motor operating on 120 volts A.C.Adjustable Register A heat outlet capable of being openedand closed.Air Speed Indi

35Terminology DefinitionLoud Ignition A condition where the air to gasmixture is off and the burner lightswith a loud noise.Main Burner Orifice The Or

36Return Goods PolicyEffective August 7, 1995, all Atwood defective returns will no longerbe repaired at the warehouses and returned to customers. Def

3737ATWOOD MOBILE PRODUCTShydro flameTMFURNACE LIMITED WARRANTYAtwood Mobile Products warrants to the original owner and subjectto the below mentioned

3838Flat RateSchedulehydro flameTMFurnacesAND DetectorsTIME ALLOWANCE SCHEDULE in hours85 DC89 AC89 8012 79II, III & IV I & II & III I &am

391223241115141617108234139212018762225195273029283031261Item # Description of Parts 1 Front Door2 Electronic Ignition Board3 Valve4 Front Discharge C

479 / 80 Series Model IdentificationApplications - This unit is typically installed in tent campers, truck campers and small travel trailers due to it

40October 1997Drawing# Description of Parts 8516 8520 8525 8531 85351 Blower Wheel4 Asmbly, Plate & Gasket6 Burner Asmbly7 Casing Extension Box8

41ENGLISH, FRANCAIS (et Canada) •Installation •MaintenanceEffective 9/1/03LITERATURE NUMBERMPD 33940hydro flameTM8500-IV Series FurnaceMODELS 8516, 85

42ENGLISH, FRANCAIS (et Canada) •Installation •MaintenanceEffective 9/1/03LITERATURE NUMBERMPD 33941hydro flameTM8500-IV-LD Series FurnaceMODELS 8516,

4343ENGLISH, FRANCAIS (et Canada) •Installation Effective 9/1/03LITERATURE NUMBERMPD 33938hydro flameTM8900-III Series FurnaceMODELS 8935, 8940Techn

44 44ENGLISH, FRANCAIS (et Canada) •Installation •MaintenanceEffective 9/1/03LITERATURE NUMBERMPD 33939hydro flameTM8500-IV 2 Stage Series FurnaceMODE

45ENGLISH, FRANCAIS (et Canada) •Installation Effective 9/1/03LITERATURE NUMBERMPD 33943hydro flameTM8900-III-LD 2 Stage Series FurnaceMODEL 2540Tech

4685-IV 1685-IV 2085-IV 2585-IV 3185-IV 351522 2-stage2334 2-stageR-25Blowers Wheels & Covers37605 Blower cover - back (outside) ✗✗ ✗ ✗ ✗ ✗✗37606

4785-IV 1685-IV 2085-IV 2585-IV 3185-IV 351522 2-stage2334 2-stageR-25Heating Elements37960 Htg Element Kit* 16, 20 (before S/N 1260456) ✗✗37961 Htg

4885-IV 1685-IV 2085-IV 2585-IV 3185-IV 351522 2-stage2334 2-stageR-25Miscellaneous37844 Air Intake Tube No Longer Available32882 Door Screen ✗✗ ✗ ✗

497912-II7900-II 16 & 208012-II85-III 16-2085-III 2585-III 31-3589-III DC89-III AC2540 2-StageBlower 33580 Blower Cover ✗✗✗34014 Blower Cover ✗✗

579-II Directional Air Box Insert (PN 36959)An air discharge diverter is now available for all 79 series furnaces. This insert has fins that are set a

507912-II7900-II 16 & 208012-II85-III 16-2085-III 2585-III 31-3589-III DC89-III AC2540 2-StageCombustion35892 Combustion Air Hose ✗✗ ✗33128 Comb

517912-II7900-II 16 & 208012-II85-III 16-2085-III 2585-III 31-3589-III DC89-III AC2540 2-Stage33566 Outlet Manifold (before S/N 0654748) ✗✗✗35936

52hydro flame FurnaceREPLACEMENT PART REFERENCESeptember 200337383 White Rodgers Valve (DC) (After Serial #0657715) ✗34006 White Rodgers Valve (AC)

5385-II 16-2085-II 2585-II 31-3589-I DC89-I AC89-II DC89-II ACFA 79DFA79PHF 80DHF 80PBlower33580 Blower Cover ✗✗✗33431 Blower Wheel ✗✗✗✗33618 Blowe

5485-II 16-2085-II 2585-II 31-3589-I DC89-I AC89-II DC89-II ACFA 79DFA79PHF 80DHF 80P33853 Recess Pan 01 White ✗✗✗✗ ✗✗✗33854 Recess Pan 02 Colonial

5585-II 16-2085-II 2585-II 31-3589-I DC89-I AC89-II DC89-II ACFA 79DFA79PHF 80DHF 80PPilot32466 1/4 x 7 Pilot Tube w/ fittings ✗✗33830 Jade Orifice

5685-1 16-2085-I 2585-I 31-35DC82 25-32DC82 35-41AC 82FA 76D FA 78 25-32FA 72DFA 72P Blower31135 Blower Wheel NLA ✗✗31139 Blower Wheel ✗✗✗ ✗32775 B

5785-1 16-2085-I 2585-I 31-35DC82 25-32DC82 35-41AC 82FA 76D FA 78 25-32FA 72DFA 72P Motor31039 Motor JA25065N (AC) ✗31036 Motor PF2040Q ✗31037 Mot

58Adapter plate for bottom discharge - from extension plenum. No seals but with alignment tabs. Use with extension plenum 33150 or 37878.37868Floor pl

685 Series Model IdentificationMODEL DESCRIPTION85 I6-II DC LP 6 SB w/o ThermModelBTU/Hr Rate (Input)16-IV = 16,00020-IV = 20,00025-IV = 25,00031-IV =

789 Series Model IdentificationMODEL DESCRIPTION89 35 DC LP 6ModelBTU/Hr Rate (Input)35 = 35,00040 - 40,000VoltageDC = direct current 12 VoltsAC = 120

8Wiring Diagram for 7900-II / 8000-IIBlackRedBlackWhiteRelayRedBlackRedBlackHigh TensionWhiteWhiteRed +12V DCNeg.Red5179 YellowWhiteGROUNDMOTORELECTRO

9COMPRESSOR / COMPRESSEURHIGH FAN / VENTILATEUR HAUTLOW FAN / VENTILATEUR BAS115VAC NEUTRAL / 115 VCA NEUTREGROUND / TERREMED FAN*/ VENTILATEUR MOY*