TablE OF COnTEnTS PAGE Furnace Introduction / Model & Serial Number Information ............... 3 General Service Information / Cautions & Safety Information ............4 Furnace Specification Sheet....................... 5 Furnace Removal ..........................6 Installation Information ........................8 Vent Assembly Installation ........................9 Return Air &...
Suburban furnaces operate on 12-volt DC power which is supplied either by a 12-volt battery or a converter system. A recreational vehicle furnace that is specifically designed for “park model” trailers operates on 120 volts AC. These are designed and tested under the same standards as the 12-volt models.
GEnEral SErViCE inFOrMaTiOn GAS SUPPLY PRESSURE REQUIREMENTS LiNE PRESSuRE: • Minimum 11” WC*, Maximum 14” WC *WC - water column VOLTAGE REQUIREMENTS VOlTAGE DC: • 12 volt D.C. Minimum 10.5 volts D.C., Maximum 13.5 volts D.C. SERVICE TOOLS REQUIRED Manometer gauge/ U-Tube Volt ohm meter capable of testing above 15 amps Module board tester #641511 Gas leak detector OR approved leak check liquid...
FurnaCE rEMOVal To replace parts or service the SUBURBAN family of RV furnaces, it is necessary to follow these steps: DD-17DSI 1. Turn off gas and power, then disconnect gas and power supply at the furnace. Label wires as necessary.
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FurnaCE rEMOVal SF-20/25/30/35/42, SF-20Q/25Q/30Q/35Q/42Q, SFV-20/25/30/35/42, SH-35/42 and SHD-2542 1. Remove the vent cap assembly from the outside access door by removing applicable screws, also the four (4) screws retaining the door to the frame. Remove the door to gain access to the furnace. 2.
There are several important aspects of the installation which will pertain to all Suburban forced draft furnaces, regardless of the model or the method in which they are installed. They are: 1. Selecting a location 2. Venting 3. Return Air 4.
VEnT aSSEMblY inSTallaTiOn VENTING- By definition of a Direct Vent Sealed Combustion Furnace, it must be vented to the outside atmosphere and also draw combustion air from outdoors. Therefore, it is imperative that the vent be unobstructed and there must be a seal between the exhaust and intake (caulking) . Refer to the vent assembly installation in the manual.
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VEnT aSSEMblY inSTallaTiOn FURNACE TIE-DOWN SCREW (FURNACE TO CABINET) OUTSIDE SKIN CAULK ALONG THE EDGE OF THE CUTOUT (ALL THE WAY AROUND) ANCHOR FURNACE CABINET TO COACH FLOOR (2) PLACES AS ILLUSTRATED BACK OF CABINET MUST BUTT AGAINST THIS EDGE OF THE FRAME DOOR FRAME CAULK BEHIND VENT CAP AS SHOWN TO SEAL BETWEEN EXHAUST AND INTAKE AND TO PREVENT...
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VEnT aSSEMblY inSTallaTiOn SF-20F, SF-25F, SF-30F, SF-35F, SF-42F, STANDARD VENT INSTALLATION INTAKE: 1/2" MINIMUM OVERLAP X" TRAILER SKIN 1" EXHAUST: 1 1/4" MINIMUM OVERLAP FRONT GAS HOOKUP MOUNTING SURFACE VENT CAP NEVER INSTALL THE EXHAUST TUBE WITH LESS THAN X" DIMENSION EXTENSION TUBES KIT NO.
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VEnT aSSEMblY inSTallaTiOn (SFV MODElS) CUTOUT FOR FURNACE ACCESS DOOR FRAME CUTOUT AS VIEWED FROM OUTSIDE R.V. SPACERS ON LEFT SIDE OF FURNACE ARE FLUSH 8.281 WITH LEFT SIDE OF .375 CUTOUT GAS CONNECTION (REAR) ELECTRICAL CONNECTION CABINET MOUNTING FURNACE BRACKET GAS CONNECTION (FRONT)
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VEnT aSSEMblY inSTallaTiOn (SFV MODElS) RAIN SHIELD INSTALLATION: APPLY CAULKING BETWEEN RV SKIN AND BACK OF RAIN SHIELD. POSITION RAIN SHIELD AS ILLUSTRATED. APPLY A SECOND LAYER OF CAULKING OVER RAIN SHIELD AND BEHIND VENT CAP AS ILLUSTRATED. FOLLOW INSTRUCTIONS FOR CAULKING VENT. CAULK BEHIND VENT CAP AS SHOWN TO SEAL BETWEEN EXHAUST AND INTAKE AND TO PREVENT MOISTURE INSIDE OUTSIDE SKIN (PANEL)
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VEnT aSSEMblY inSTallaTiOn (nT SEriES) VENT TUBE INSTALLATION "X" TRAILOR SKIN Y" 1 3/8" VENT TUBE (EXHAUST) 8" X 2" O.D. VENT CAP VENT TUBE (INTAKE) SEE CHART 1 1/4" MIN. OVERLAP ON EXHAUST MOUNTING SURFACE 1/2" MIN. OVERLAP OF INTAKE TUBE 21"...
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VEnT aSSEMblY inSTallaTiOn (nT SEriES) VENT TUBE INSTALLATION NT-16S "X" Y" 3/8" TRAILOR SKIN VENT TUBE (EXHAUST) 8" X 2" O.D. VENT CAP VENT TUBE ASSY. (INTAKE) SEE CHART 1 1/4" MIN. OVERLAP MOUNTING SURFACE 1/2" MIN. OVERLAP PART NO. INTAKE TUBE LENGTH ONLY "X"...
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VEnT aSSEMblY inSTallaTiOn (nT SEriES) THE SCREW PROVIDED MUST BE USED ON ALL VENT CAP INSTALLATIONS *3 1/2" FROM CENTER LINE OF INTAKE TO CENTER LINE OF EXHAUST ** 7 1/2" FROM CENTER LINE TWO 2 1/4" DIA HOLES OF INTAKE TO FLOOR INSIDE WALL OUTSIDE SKIN EXHAUST...
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VEnT aSSEMblY inSTallaTiOn (nT40 & p40) HEAT SHIELD COLLAR VENT CAP EXHAUST * 3.50" FROM CENTER LINE OF INTAKE TO CENTER LINE OF EXHAUST ** 7.50" FROM CENTER LINE OF INTAKE TO FLOOR (2) 3.00" DIA. HOLES INSIDE WALL 1 / 8 OUTSIDE SKIN AIR INTAKE FURNACE...
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VEnT aSSEMblY inSTallaTiOn (nT40 & p40) 3 1/2" X 7" CUTOUT THRU COMBUSTIBLE CONSTRUCTION MAXIMUM WALL THICKNESS FOR THIS 3 1/2" TYPE INSTALLATION IS 2 1/4" 3 1/2" 2 1/4" MAX. HEAT SHIELD COLLAR CAULK BEHIND VENT CAP AS WARNING: SHOWN TO SEAL BETWEEN 7 1/2"...
DuCTinG Suburban furnaces require that a minimum duct area be maintained throughout entire duct system including through the register. it is very important to adhere to the minimum duct area in order to keep the furnace from cycling on high limit and to assure proper operation of the sail switch (sometimes referred to as a microswitch.) NOTE: (Refer to the...
rETurn air & DuCTinG inSTallaTiOn rEQuirEMEnTS DuCTS bTM DuCT TOp DuCT l & r SiDE DuCT rETurn air MODElS FrOnT baCK lEFT riGhT rEQ’D SQ inCh SQ inCh SQ inCh SQ inCh DD-17DSI SEE *1 0” 0” 0” 0” 0” NT 12S 3/8”...
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rETurn air & DuCTinG inSTallaTiOn rEQuirEMEnTS DuCTS bTM DuCT TOp DuCT l & r SiDE DuCT rETurn air MODElS FrOnT baCK lEFT riGhT rEQ’D SQ inCh SQ inCh SQ inCh SQ inCh SF 20/20F 1” 0” 0” 0” 0” 0” 2 - 4”...
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rETurn air & DuCTinG inSTallaTiOn rEQuirEMEnTS DuCTS bTM DuCT TOp DuCT l & r SiDE DuCT rETurn air MODElS FrOnT baCK lEFT riGhT rEQ’D SQ inCh SQ inCh SQ inCh SQ inCh SFV 20/20F 1” 1” 0” 0” 1” 1” SEE *4 52”...
ElECTriCal SupplY inFOrMaTiOn CONNECTING ELECTRICAL SUPPLY CAUTION: This furnace is designed for negative ground 12 volt D.C. system only. Do not attempt to alter the furnace for a positive ground system or connect the furnace directly to 120 volts A.C. Damage to furnace component parts will occur. Be sure all wiring to the furnace is of heavy enough gauge to keep the voltage drop through it to a minimum and to provide enough power for start-up surge.
FurnaCE SpECiFiCaTiOnS 12 VDC MODElS inpuT MOTOr STaTiC C.F.M. MODEl DESCripTiOn GaS TYpE VOlTaGE bTu/hr DiaMETEr DraW prESSurE MaX. 6.5=2.5 IN. SF 20/20F Ducted 20,000 PROPANE 12 VDC 3” MOTOR .2” WC 8.5=3 IN 7.0=3 IN. SF 20Q/20FQ Ducted 20,000 PROPANE 12 VDC 3”...
SEQuEnCE OF OpEraTiOn FOr Fan COnTrOl MODulE bOarD parT nuMbEr 520820 TiME linE DESCripTiOn The wall thermostat controls the operation of the furnace by reacting to room temperature. This allows current to flow through the ON/OFF switch to the module board. Start Time The module board constantly checks for a minimum 9.5 volts.
SEQuEnCE OF OpEraTiOn FOr 24 VaC Fan COnTrOl MODulE bOarD parT nuMbEr 520947 TiME linE DESCripTiOn The wall thermostat controls the operation of the furnace by reacting to room temperature. This allows current to flow through the ON/OFF switch to the module board. Start Time The module board constantly checks for a minimum 18 volts for normal operation.
SEQuEnCE OF OpEraTiOn FOr ShD-2542 TiME linE DESCripTiOn The wall thermostat controls the operation of the dual stage furnace by reacting to room temperature. This allows current to flow through the ON/OFF switch to the Blower Speed Control Board then to the Module Board. Start Time The module board constantly checks for a minimum 9.5 volts.
SEQuEnCE OF OpEraTiOn FOr FurnaCES EQuippED WiTh TiME DElaY TiME linE DESCripTiOn The wall thermostat controls the operation of the furnace by reacting to room temperature upon a call from the thermostat, this allows current to flow through the ON/OFF switch then to the relay.
SErViCE hinTS, DiaGnOSiS, and COrrECTiVE MEaSurES FOR THE IGNITION SYSTEMS OF SUBURBAN 24 VOLT ELECTRONIC IGNITION GAS FURNACES WITH TIME DELAY it is important to determine the type problem being CauTiOnS experienced, then the proper checkout procedure can be made. The following is a list of problems, how to identify in 1.
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SErViCE hinTS, DiaGnOSiS, and COrrECTiVE MEaSurES FOR THE IGNITION SYSTEMS OF SUBURBAN 24 VOLT ELECTRONIC IGNITION GAS FURNACES WITH TIME DELAY c. Gas pressure OK - check for obstruction in main burner; 6. Customer complains of unit going into lockout only once...
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WirinG DiaGraMS TIME DELAY RELAY N.O. LIMIT SAIL SW. N.C. SWITCH MOTOR N.O. TIME DELAY RELAY N.O. MODULE VALVE BOARD SWITCH N.C. Y GROUNDING TERMINAL MODULE SAIL LIMIT BOARD SWITCH SW. N.C. N.O. ELECTRODE ELECTRODE THERMOSTAT N.O. VALVE VALVE MOTOR 12 VOLTS D.C CAUTION: DO NOT HI-POT ALL WIRES ARE 18 AWG UNLESS OTHERWISE SPECIFIED...
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WirinG DiaGraMS LIMIT SAIL SW. N.C. SWITCH MOTOR N.O. MODULE VALVE BOARD SWITCH N.C. Y GROUNDING POWER TERMINAL SAIL LIMIT MODULE SWITCH SW. N.C. BOARD N.O. ELECTRODE ELECTRODE THERMOSTAT N.O. VALVE VALVE MOTOR 12 VOLTS D.C CODE COLOR ALL WIRES ARE 18 AWG UNLESS OTHERWISE SPECIFIED CAUTION: DO NOT HI-POT (DIELECTRIC HIGH VOLTAGE TEST) THIS UNIT AFTER ORANGE...
SF, Sh anD ShD-2542 ElECTrODE Gap SpECiFiCaTiOnS anD pOSiTiOninG To assure consistent ignition of the burner, it is important for the electrode to be positioned properly over the top of the burner. When replacing the electrode, or should you be experiencing ignition type problems, the electrode should be positioned as outlined in the drawing.
nT ElECTrODE Gap SpECiFiCaTiOnS anD pOSiTiOninG To assure consistent ignition of the burner, it is important for the electrode to be positioned properly over the top of the burner. When replacing the electrode, or should you be experiencing ignition type problems, the electrode should be positioned as outlined in the drawing.
MainTEnanCE Preventative maintenance is essential if an RV owner is to have reliable, safe operation of his furnace. Two important areas to watch closely in order to assure safe, reliable operation are the venting and the main burner. An obstruction in the vent or main burner will reduce the combustion air which results in incomplete combustion. When- ever incomplete combustion occurs, the by-products are carbon monoxide (CO) and soot.
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® Suburban Division 676 Broadway Street Dayton, Tennessee 37321 423-775-2131 Fax 423-775-7015 www.RVComfort.com All information published in this manual is subject to change without notice.
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