SERVICE & TRAINING MANUAL

Transcription

1 V FUNACES SEVICE & TAINING MANUAL 676 Broadway Street Dayton, Tennessee Fax All information published in this manual is subject to change without notice.

2 TAE OF CONTENTS PAGE Furnace Introduction / Model & Serial Number Information... 3 General Service Information / Cautions & Safety Information... 4 Furnace Specification Sheet... 5 Furnace emoval... 6 Installation Information... 8 Vent Assembly Installation... 9 eturn Air & Ducting Information eturn Air & Ducting equirements Electrical Supply Information Furnaces Specifications Sequence of Operation (12 VDC Fan Control Module Board) Sequence of Operation (24 VAC Fan Control Module Board) Sequence of Operation (SHD-2542 Furnace) Sequence of Operation (Time Delay elay Equipped Furnaces) Troubleshooting Flow Chart (Furnaces Equipped with Time Delay elay) Troubleshooting Flow Chart (Furnaces Equipped with Fan Control Module Board) Service Hints, Diagnosis sheet for (24 VAC Time Delay elay Equipped Furnaces) Furnace iring Diagrams SF, SH and SHD-2542 Electrode Gap Specifications & Positioning NT and Park Model Electrode Gap Specifications Maintenance... 39

3 FUNACE INTODUCTION Suburban furnaces installed in recreational vehicles are classified as Direct Vent Sealed Combustion Furnaces. A forced draft furnace utilizes a sealed combustion chamber which is vented to the outside atmosphere. The intake air for combustion is also taken from outdoors and is completely isolated from the room air. A motor is used to drive an impeller wheel to draw intake air into the chamber to support combustion and force the exhaust gases through the furnace chamber to the outside atmosphere. A second impeller wheel (driven by the same motor yet totally isolated from the combustion air) is used to circulate room air across the furnace chamber where it is heated. The blower then forces the hot air into the living area either through a duct system or through a front grille on the furnace cabinet on direct discharge models. 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. Suburban forced draft combustion furnaces used in recreational vehicles are designed for use with Propane gas. Although a few recreational vehicle furnaces are approved for use with natural gas, one should never attempt to convert such a unit to natural gas unless the conversion is approved by the manufacturer of the furnace. NOTE: Our Service technicians are available to assist you in making repairs or parts replacements from 8:00 AM to 5:00 PM Eastern Standard Time, Monday through Friday (except holidays), by calling EXT address: SMCSales@suburbanmfg.com MODEL & SEIAL NUMBE INFOMATION Model and Serial Numbers for Suburban Furnaces are located on a Data Plate attached to the furnace assembly. Below is an example: MODEL NO. / NUMÉO DE MODÉLE SF-35F SEIAL NO./ NUMÉO DE SÉIE STOCK NO INPUT BTU/H. DEBIT CALOIFIQUE OUTPUT BTU/H. CLAIFIQUE MANIFOLD PESSUE PESSION TUBULUE 10.0.C. 27, C. MODEL EAKDON SF-35F Suburban Furnace 35,000 BTU Front Gas SEIAL # EAKDON ear of MFG (2009) eek of (31) Sequential S#(02771) OIFICE SIZE DIMENSION DE L INJECTEU #51 TPE OF GAS ESPECE DE GAZ LP 3

4 GENEAL SEVICE INFOMATION GAS SUPPL PESSUE EQUIEMENTS LINE PESSUE: Minimum 11 C*, Maximum 14 C *C - water column VOLTAGE EQUIEMENTS VOLTAGE DC: 12 volt D.C. Minimum 10.5 volts D.C., Maximum 13.5 volts D.C. SEVICE TOOLS EQUIED Manometer gauge/ U-Tube Volt ohm meter capable of testing above 15 amps Module board tester # Gas leak detector O approved leak check liquid Assorted wrenches Assorted hand tools Safety glasses CAUTIONS & SAFET INFOMATION 1. Never use a battery charger to power or test an electronic ignition furnace as they sometimes provide more than 14.5 DC Volts that could damage the module board. 2. Never operate the furnace with the electrode wire disconnected nor with the electrode assembly removed from the furnace. 3. Never use a screwdriver on any part of the electrode assembly while the furnace is in operation. 4. Be certain that the spark from the electrode never reaches the flame sensor portion of the electrode assembly on remote sense units. 5. Install the furnace so electrical components and connections are protected from water. 6. ire the furnace direct to the battery when possible. 7. Use two wrenches on gas fittings when tightening gas connections. 8. Verify voltage of furnace, do not use 120 volt AC with 12 volt DC. 9. Do not modify the furnace in any way. 10. Do not vent the furnace to an outside enclosed porch area or where the vent is covered or obstructed. 11. Always meet or exceed minimum duct requirements. Also meet the minimum return air requirements. 12. Furnace must be installed and vented correctly. efer to the Installation Manual for the specific model furnace. 13. Do not install aftermarket components. 4

5 SUBUBAN V FUNACES SPEC SHEET BTU/h INPUT Height idth Depth Ignition Shipping eight 12 VDC DIECT DISCHAGE NT-16SEQ 16, /8 9 3/ /4 Electronic 27 NT-20SEQ 19, /8 9 3/ /4 Electronic VDC DUCTED FUNACES NT-16SQ 16, /8 9 3/8 22 3/4-29 1/2 Electronic 27 NT-20SQ 19, /8 9 3/8 23 3/8-30 1/8 Electronic 27 NT-30SP 30, / Electronic 40 NT-34SP 34, / Electronic 40 NT-40 40, / Electronic 42 SF-20Q/20FQ 20, / Electronic 35 SF-25Q/25FQ 25, / Electronic 35 SF-30Q/30FQ 30, / Electronic 35 SF-35Q/35FQ 35, / Electronic 35 SF-42Q/42FQ 40, / Electronic 35 SH-35Q/35FQ 35, / Electronic 40 SH-42Q/42FQ 40, / Electronic 42 Accessories 6258AC 6258AP 6267AC Description DOO, Optional Access, Colonial hite, Standard SF & SFQ Models DOO, Optional Access, Polar hite, Standard SF & SFQ Models DOO, Optional Access, Colonial hite, Standard SH & SHQ Models SFV-20 20, / Electronic 35 SFV-25 25, / Electronic 35 SFV-30 30, / Electronic 35 SFV-35 35, / Electronic 35 SFV-42 40, / Electronic 35 SHD /40, / Electronic VAC PAK MODEL FUNACES P-40 40, / Electronic 46 Accessories Description Duct Cover Duct Collar Duct Collar ain Shield Bottom Duct Gasket, NT-24/30/34SP, NT-40, P Bottom Duct Gasket, SF Models EXCEPT SF-42/42F Bottom Duct Kit /Gasket, NT-24/30/34SP, NT-40, P Bottom Duct Kit /Gasket, SF Models EXCEPT SF-42/42F, SH-35/35F Bottom Duct Kit /Gasket and Door, SF-42/42F Bottom Duct Kit /Gasket, SH-42/42F, SHD

6 FUNACE EMOVAL To replace parts or service the SUBUBAN family of V 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. 2. emove the vent cap assembly by removing applicable screws. 3. emove the cabinet front two (2) screws. 4. emove the applicable screws securing the furnace to the coach floor. 5. emove duct from side of furnace, if equipped. 6. emove the furnace from the cabinet area to gain access to combustion chamber and applicable parts. 7. Some parts can be accessed without removal of the complete furnace. 8. To re-install, reverse this procedure. 9. ewire applicable wires and perform a leak test on all fittings. Perform a drop pressure test. NT-12/16/20S/SQ 1. Turn off gas and power, then disconnect gas and power supply at the furnace. Label wires as necessary. 2. emove the vent cap assembly by removing applicable screws. 3. emove the cabinet front two (2) screws. 4. emove the (1) one tie down screw securing the chamber to the cabinet. 5. emove the furnace from the cabinet by pulling chamber outward completely to gain access to all controls and applicable parts. 6. To re-install, reverse this procedure. 7. ewire applicable wires and perform a leak test on all fittings. Perform a drop pressure test. NT-12/16/20SE/SEQ 1. Turn off gas and power, then disconnect gas and power supply at the furnace. Label wires as necessary. 2. emove the vent cap assembly by removing applicable screws. 3. emove the cabinet front two (2) screws. 4. emove the (2) two tie down screws securing the chamber to the cabinet. 5. emove the furnace from the cabinet by pulling chamber outward completely to gain access to all controls and applicable parts. 6. To re-install, reverse this procedure. 7. ewire applicable wires and perform a leak test on all fittings. Perform a drop pressure test. NT-24/30/34SP and NT Turn off gas and power, then disconnect gas and power supply at the furnace. Label wires as necessary. 2. emove the vent cap assembly by removing applicable screws and one (1) flue retaining screw. Not applicable to NT emove the cabinet front two (2) screws. 4. emove the (2) two tie down screws securing the chamber to the cabinet. 5. emove the furnace from the cabinet by pulling chamber outward completely to gain access to all controls and applicable parts. 6. To re-install, reverse this procedure. 7. ewire applicable wires and perform a leak test on all fittings. Perform a drop pressure test. 6

7 FUNACE EMOVAL SF-20/25/30/35/42, SF-20Q/25Q/30Q/35Q/42Q, SFV-20/25/30/35/42, SH-35/42 and SHD emove the vent cap assembly from the outside access door by removing applicable screws, also the four (4) screws retaining the door to the frame. emove the door to gain access to the furnace. 2. Turn off gas and power, then disconnect gas and power supply at the furnace. Label wires as necessary. 3. emove the (1) one tie down screw securing the chamber to the cabinet. 4. emove the furnace from the cabinet by pulling chamber outward completely to gain access to all controls and applicable parts. 5. To re-install, reverse this procedure. 6. ewire applicable wires and perform a leak test on all fittings. Perform a drop pressure test. SF-20/25/30/35/42F, SF-20FQ/25FQ/30FQ/35FQ/42FQ, SFV-20/25/30/35/42F and SH-35/42F 1. Turn off gas and power, then disconnect gas and power supply at the furnace. Label wires as necessary. 2. emove the vent cap assembly by removing applicable screws. 3. emove the cabinet front two (2) screws. 4. emove the (1) one tie down screw securing the chamber to the cabinet. 5. emove the furnace from the cabinet by pulling chamber outward completely to gain access to all controls and applicable parts. 6. To re-install, reverse this procedure. 7. ewire applicable wires and perform a leak test on all fittings. Perform a drop pressure test. NOTE: ON SFV MODELS, EMOVE EXTA SCES FO CHAMBE EMOVAL. P-30S and P Turn off gas and power, then disconnect gas and power supply at the furnace. Label wires as necessary. 2. emove the vent cap assembly by removing applicable screws and one (1) flue retaining screw. (Not applicable to P40.) 3. emove the cabinet front two (2) screws. 4. emove the (2) two tie down screw securing the chamber to the cabinet. 5. emove the furnace from the cabinet by pulling chamber outward completely to gain access to all controls and applicable parts. 6. To re-install, reverse this procedure. 7. ewire applicable wires and perform a leak test on all fittings. Perform a drop pressure test. 7

8 INSTALLATION INFOMATION 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. eturn Air 4. Ducting 5. Electrical Supply efer to the furnace installation manual for all installation requirements. Location and Installation- Locate the furnace near lengthwise center of the coach. 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 cabinet to combustible construction as listed in the installation manual for your specific furnace model. Secure furnace cabinet to the floor of the coach using the holes provided in the furnace cabinet. Figure 1 8

9 VENT ASSEM 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). efer to the vent assembly installation in the manual. The vent must be straight. There can be no offsets or turns in the vent. All vent tubes which connect to the furnace exhaust and intake must overlap a minimum of 1/2 on intake, and 1 1/4 on exhaust. Check your furnace model number for vent installation procedures. Vents cannot be altered as supplied from the factory. OUTSIDE SKIN (PANEL) TUBE, INTAKE AI ITH GASKET VENT CAP AND EXHAUST TUBE, AI INTAKE ITH GASKET VENT CAP AND EXHAUST TUBE CAULK BEHIND VENT CAP AS SHON TO SEAL BETEEN EXHAUST AND INTAKE AND TO PEVENT MOISTUE INSIDE FUNACE COMPATMENT. APPL CAULKING GENEOUSL AOUND PEIMETE OF VENT CAP AND ACOSS CENTE AS SHON. CENTE PUTT STIP IS ESSENTIAL. DETAIL "A" (2) 2 1/4" DIA. HOLES SEE DETAIL "A" EMOVAE PANEL OF COACH ALL MUST SEAL ATE TIGHT OUTSIDE SKIN (PANEL) FONT ELECTICAL CONNECTION GAS CONNECTION FUNACE CABINET Figure 2 SF & SFQ MODELS INSIDE ALL 2" MAXIMUM ALL THICKNESS OUTSIDE SKIN (PANEL) TUBE, INTAKE AI ITH GASKET VENT CAP AND EXHAUST TUBE, AI INTAKE ITH GASKET VENT CAP AND EXHAUST TUBE 3 13" " 8 CAULK BEHIND VENT CAP AS SHON TO SEAL BETEEN EXHAUST AND INTAKE AND TO PEVENT MOISTUE INSIDE FUNACE COMPATMENT. APPL CAULKING GENEOUSL AOUND PEIMETE OF VENT CAP AND ACOSS CENTE AS SHON. CENTE PUTT STIP IS ESSENTIAL. DETAIL "A" (2) 2 1/4" DIA. HOLES 8 7" " " 4 CL SEE DETAIL "A" 9 3" 4 EMOVAE PANEL OF COACH ALL MUST SEAL ATE TIGHT OUTSIDE SKIN (PANEL) FONT FUNACE CABINET ELECTICAL CONNECTION GAS CONNECTION INSIDE ALL 2" MAXIMUM ALL THICKNESS Figure 2A SH MODELS 9

10 VENT ASSEM INSTALLATION FUNACE TIE-DON SCE (FUNACE TO CABINET) OUTSIDE SKIN CAULK ALONG THE EDGE OF THE CUTOUT (ALL THE A AOUND) ANCHO FUNACE CABINET TO COACH FLOO (2) PLACES AS ILLUSTATED BACK OF CABINET MUST BUTT AGAINST THIS EDGE OF THE FAME DOO FAME CAULK BEHIND VENT CAP AS SHON TO SEAL BETEEN EXHAUST AND INTAKE AND TO PEVENT MOISTUE INSIDE FUNACE COMPATMENT. APPL CAULKING GENEOUSL AOUND PEIMETE OF VENT CAP AND ACOSS CENTE AS SHON. CENTE PUTT STIP IS ESSENTIAL. ELECTICAL CONNECTION GAS CONNECTION CL AI INTAKE TUBE ITH GASKET 6 SCES (SUPPLIED) 2" MAX. SECUE FAME TO OUTE PANEL ITH SCES (16 PLACES) Figure 3 SF & SFQ MODELS 4 SCES DOO MOUNTING FUNACE ACCESS DOO VENT CAP & EXHAUST TUBE FUNACE TIE-DON SCE (FUNACE TO CABINET) OUTSIDE SKIN CAULK ALONG THE EDGE OF THE CUTOUT (ALL THE A AOUND) ANCHO FUNACE CABINET TO COACH FLOO (2) PLACES AS ILLUSTATED BACK OF CABINET MUST BUTT AGAINST THIS EDGE OF THE FAME DOO FAME CAULK BEHIND VENT CAP AS SHON TO SEAL BETEEN EXHAUST AND INTAKE AND TO PEVENT MOISTUE INSIDE FUNACE COMPATMENT. APPL CAULKING GENEOUSL AOUND PEIMETE OF VENT CAP AND ACOSS CENTE AS SHON. CENTE PUTT STIP IS ESSENTIAL. ELECTICAL CONNECTION GAS CONNECTION CL AI INTAKE TUBE ITH GASKET 6 SCES (SUPPLIED) 2" MAX. SECUE FAME TO OUTE PANEL ITH SCES (16 PLACES) Figure 3A SH & SHD-2542 MODELS 4 SCES DOO MOUNTING FUNACE ACCESS DOO VENT CAP & EXHAUST TUBE 10

11 VENT ASSEM INSTALLATION SF-20F, SF-25F, SF-30F, SF-35F, SF-42F, STANDAD VENT INSTALLATION 1" INTAKE: 1/2" MINIMUM OVELAP EXHAUST: 1 1/4" MINIMUM OVELAP X" TAILE SKIN FONT GAS HOOKUP DIA DIA. C L EXHAUST CL INTAKE MOUNTING SUFACE X" DIMENSION EXTENSION TUBES KIT NO. 0" TO 1 1/2" /2" TO 3" USE VENT SUPPLIED ITH FUNACE 3" TO 4 1/2" /2" TO 7 1/2" /2" TO 9" NEVE INSTALL THE EXHAUST TUBE ITH LESS THAN 1 1/4" OVELAP, O THE INTAKE TUBE ITH LESS THAN 1/2" OVELAP. STANDAD VENT ASSEM FUNISHED ITH FUNACE. SPECIAL EXTENSION TUBES, IF NEEDED, MUST BE ODEED SEPAATEL. EXTENSION KITS COME ITH COMPLETE INSTALLATION INSTUCTIONS. VENT CAP Figure 4 SF & SFQ MODELS SH-35F, SH-42F STANDAD VENT INSTALLATION 1" INTAKE: 1/2" MINIMUM OVELAP EXHAUST: 1 1/4" MINIMUM OVELAP X" TAILE SKIN FONT GAS HOOKUP DIA DIA. C L EXHAUST CL INTAKE MOUNTING SUFACE VENT CAP X" DIMENSION 0" TO 1 1/2" 1 1/2" TO 3" 3" TO 4 1/2" 4 1/2" TO 7 1/2" 7 1/2" TO 9" EXTENSION TUBES KIT NO USE VENT SUPPLIED ITH FUNACE NEVE INSTALL THE EXHAUST TUBE ITH LESS THAN 1 1/4" OVELAP, O THE INTAKE TUBE ITH LESS THAN 1/2" OVELAP. STANDAD VENT ASSEM FUNISHED ITH FUNACE. SPECIAL EXTENSION TUBES, IF NEEDED, MUST BE ODEED SEPAATEL. EXTENSION KITS COME ITH COMPLETE INSTALLATION INSTUCTIONS. Figure 4A SH Models 11

12 VENT ASSEM INSTALLATION (SFV MODELS) FUNACE FLOO CABINET MOUNTING ACKET (ONE PE SIDE) GAS CONNECTION (EA) ELECTICAL CONNECTION GAS CONNECTION (FONT) * 8.281" 2.000" MAX. TIE-DON SCE (FUNACE TO CABINET) OUTSIDE SKIN BACK OF CABINET MUST BUTT AGAINST THIS EDGE OF FAME DOO FAME * CUTOUT FO FUNACE ACCESS DOO FAME CUTOUT AS VIEED FOM OUTSIDE SPACES ON LEFT SIDE.V. OF FUNACE AE FLUSH 8.281* ITH LEFT SIDE OF.375 CUTOUT CABINET MOUNTING ACKET SECUE FAME TO OUTE PANEL ITH SCES (16 PLACES) FUNACE ACCESS DOO **.220 MIN FLOO ** SEE NOTCH DETAIL A CL LC FUNACE ACKET * 4 SCES DOO MOUNTING ANCHO FUNACE TO FLOO USING (2) #10 X 3/4 SCES POVIDED " * CAULK BEHIND VENT CAP AS SHON TO SEAL BETEEN EXHAUST AND INTAKE AND TO PEVENT MOISTUE INSIDE FUNACE COMPATMENT. APPL CAULKING GENEOUSL AOUND PEIMETE OF VENT CAP AND ACOSS CENTE AS SHON. CENTE PUTT STIP IS ESSENTIAL. **NOTCH DETAIL** FLOO AND OUTE SKIN MUST BE NOTCHED AS SHON BELO..220 MIN. (HEIGHT).625 MIN. (THICKNESS) CAULK ALONG THE EDGE OF THE CUTOUT (ALL THE A AOUND) AI INTAKE TUBE ITH GASKET VENT CAP & EXHAUST TUBE 6 SCES SUPPLIED MIN. (IDTH) CABINET SUPPOT ACKET ELDED TO CABINET ANCHO ACKET TO FLOO USING (2) #10 X 3/4 SCES POVIDED DETAIL A Figure 5 SFV-20F, 25F, 30F, 35F, 42F VENT INSTALLATION FO VETICAL MOUNT NEVE INSTALL THE EXHAUST TUBE ITH LESS THAN 1 1/4" OVELAP, O THE INTAKE TUBE ITH LESS THAN 1/2" OVELAP. "X" ACKET EA VETICAL MOUNTING-USE IF POSSIE TAILE SKIN 2 3 4" DIA. TP. C L EXHAUST & INTAKE SUBUBAN DO NOT OCK OPENINGS HOT VENT CAP X" DIMENSION 0" TO 1 1/2" 1 1/2" TO 3" 3" TO 4 1/2" 4 1/2" TO 7 1/2" 7 1/2" TO 9" GASKET, BOTTOM DUCT EXTENSION TUBES KIT NO USE VENT SUPPLIED ITH FUNACE MOUNTING SUFACE ACKET, CABINET MOUNTING (ONE PE SIDE) STANDAD VENT ASSEM FUNISHED ITH FUNACE. SPECIAL EXTENSION TUBES, IF NEEDED, MUST BE ODEED SEPAATEL. EXTENSION KITS COME ITH COMPLETE INSTALLATION INSTUCTIONS. Figure 5A 12

13 VENT ASSEM INSTALLATION (SFV MODELS) Figure 6 EXHAUST & INTAKE LC AIN SHIELD INSTALLATION: APPL CAULKING BETEEN V SKIN AND BACK OF AIN SHIELD. POSITION AIN SHIELD AS ILLUSTATED. APPL A SECOND LAE OF CAULKING OVE AIN SHIELD AND BEHIND VENT CAP AS ILLUSTATED. FOLLO INSTUCTIONS FO CAULKING VENT. CAULK BEHIND VENT CAP AS SHON TO SEAL BETEEN EXHAUST AND INTAKE AND TO PEVENT MOISTUE INSIDE FUNACE COMPATMENT. APPL CAULKING GENEOUSL AOUND PEIMETE OF VENT CAP AND ACOSS CENTE AS SHON. CENTE PUTT STIP IS ESSENTIAL. OUTSIDE SKIN (PANEL) TUBE, INTAKE AI ITH GASKET EMOVAE PANEL OF COACH ALL MUST SEAL ATE TIGHT VENT CAP & EXHAUST TUBE SEE DETAIL "A" 8.000" DETAIL "A" 2.062" OUTSIDE SKIN (PANEL) VENT CAP & EXHAUST TUBE (SECUE ITH 6 SCES) " GAS CONNECTION (EA) (SFV-35) ELECTICAL CONNECTION TUBE, AI INTAKE ITH GASKET 2.060" 3.375" FUNACE CABINET GAS CONNECTION (FONT) (SFV-35F) FONT C L CUTOUT CFUNACE L (2) DIA. HOLES INSIDE ALL EMOVAE PANEL IGHT SIDE OF CUTOUT 2.000" MAX. ALL THICKNESS ANCHO FUNACE TO FLOO USING THE (4) #10 X 3/4 SCES POVIDED SECUE CABINET MOUNTING KTS TO CABINET ITH (2) #8 X 1/2 SCES CUT OUT AS VIEED FOM INSIDE.V. FLOO SFV-20, 25, 30, 35, 42 VENT INSTALLATION FO VETICAL MOUNT "X" ACKET EA VETICAL MOUNTING-USE IF POSSIE NEVE INSTALL THE EXHAUST TUBE ITH LESS THAN 1 1/4" OVELAP, O THE INTAKE TUBE ITH LESS THAN 1/2" OVELAP. TAILE SKIN " DIA. TP. SUBUBAN DO NOT OCK OPENINGS HOT VENT CAP X" DIMENSION 0" TO 1 1/2" 1 1/2" TO 3" 3" TO 4 1/2" 4 1/2" TO 7 1/2" 7 1/2" TO 9" GASKET, BOTTOM DUCT EXTENSION TUBES KIT NO. USE VENT SUPPLIED ITH FUNACE MOUNTING SUFACE ACKET, CABINET MOUNTING (ONE PE SIDE) STANDAD VENT ASSEM FUNISHED ITH FUNACE. SPECIAL EXTENSION TUBES, IF NEEDED, MUST BE ODEED SEPAATEL. EXTENSION KITS COME ITH COMPLETE INSTALLATION INSTUCTIONS. Figure 6A 13

14 VENT ASSEM INSTALLATION (NT SEIES) VENT TUBE INSTALLATION 1 3/8" "X" VENT TUBE (EXHAUST) 8" X 2" O.D. VENT TUBE (INTAKE) SEE CHAT " TAILO SKIN VENT CAP 1 1/4" MIN. OVELAP ON EXHAUST 2 1/4" DIA. 7 1/2" PAT NO. MOUNTING SUFACE 21" INTAKE TUBE LENGTH ONL X " O.D. X 2 3/4" SPECIAL X " O.D. X 5" *STANDAD X ' O.D. X 7 1/4" SPECIAL NEVE INSTALL VENT TUBES ITH LESS THAN 1/2" OVELAP ON INTAKE & 1 1/4" ON EXHAUST 2 1/4" DIA. 1/2" MIN. OVELAP OF INTAKE TUBE "X" DIMENSION 21" TO 23 1/4" 23 1/4" TO 25 1/2" 25 1/2" TO 27 3/4" STANDAD TUBE FUNISHED ITH FUNACE. THE SPECIAL TUBES, IF NEEDED, MUST BE ODEED. Figure 8 NT 12/16/20SE INSTALLING VENT CAP HOLE DIA. IN OUTE SKIN MA BE 2 1/4" IF OPENING CUT IN COMBUSTIE ALL IS CUT AS ILLUSTATED IN FIGUES 3 O 4. HOLE DIA. MUST BE 2 3/4" IF THE 4 X 7 1/2" OPENING AS SHON IN FIGUE 4 IS NOT CUT THOUGH COMBUSTIE ALL. IMPOTANT: VENT CAP AND TUBE ASS. MUST BE INSTALLED FOM OUTSIDE OF COACH. TAILE SKIN OUTLINE OF FUNACE CAULK BEHIND VENT CAP AS SHON TO SEAL BETEEN EXHAUST AND INTAKE AND TO PEVENT MOISTUE INSIDE FUNACE COMPATMENT. APPL CAULKING GENEOUSL AOUND PEIMETE OF VENT CAP AND ACOSS CENTE AS SHON. CENTE PUTT STIP IS ESSENTIAL. INTAKE TUBE VENT CAP & EXHAUST TUBE ASSEM Figure 9 NT 12/16/20S and SE 14

15 VENT ASSEM INSTALLATION (NT SEIES) VENT TUBE INSTALLATION NT-16S 3/8" "X" VENT TUBE (EXHAUST) 8" X 2" O.D. VENT TUBE ASS. (INTAKE) SEE CHAT " TAILO SKIN VENT CAP 1 1/4" MIN. OVELAP 2 1/4" DIA. 7 1/2" 2 1/4" DIA. MOUNTING SUFACE 1/2" MIN. OVELAP PAT NO. X X X INTAKE TUBE LENGTH ONL 2' O.D. X 3" STANDAD 2' O.D. X 5" SPECIAL 2' O.D. X 7 1/4" SPECIAL "X" DIMENSION 22 3/4" TO 25" 25" TO 27 1/4" 27 1/4" TO 29 1/2" NEVE INSTALL THE EXHAUST TUBE ITH LESS THAN 1 1/4" OVELAP, O THE INTAKE TUBE ITH LESS THAN 1/2" OVELAP. STANDAD TUBE FUNISHED ITH FUNACE. THE SPECIAL TUBES, IF NEEDED, AE TO BE ODEED. Figure 10 NT 12/16S VENT TUBE INSTALLATION NT-20S "X" 1" VENT TUBE (EXHAUST) 8" X 2" O.D. VENT TUBE ASS. (INTAKE) SEE CHAT " TAILO SKIN VENT CAP 1 1/4" MIN. OVELAP 2 1/4" DIA. 7 1/2" PAT NO. X X X MOUNTING SUFACE INTAKE TUBE LENGTH ONL 2' O.D. X 3" STANDAD 2' O.D. X 5" SPECIAL 2' O.D. X 7 1/4" SPECIAL "X" DIMENSION 23 3/8" TO 25 5/8" 25 5/8" TO 27 7/8" 27 7/8" TO 30 1/8" 2 1/4" DIA. 1/2" MIN. OVELAP NEVE INSTALL THE EXHAUST TUBE ITH LESS THAN 1 1/4" OVELAP, O THE INTAKE TUBE ITH LESS THAN 1/2" OVELAP. Figure 11 NT 20S STANDAD TUBE FUNISHED ITH FUNACE. THE SPECIAL TUBES, IF NEEDED, AE TO BE ODEED. 15

16 VENT ASSEM INSTALLATION (NT SEIES) *3 1/2" FOM CENTE LINE OF INTAKE TO CENTE LINE OF EXHAUST ** 7 1/2" FOM CENTE LINE OF INTAKE TO FLOO TO 2 1/4" DIA HOLES INSIDE ALL 13 VENT CAP THE SCE POVIDED MUST BE USED ON ALL INSTALLATIONS OUTSIDE SKIN EXHAUST 2 3/4 AI INTAKE FUNANCE 12 7/16 6 7/32 3 1/2 * FLOO 7 1/2 * * ASHE GAS FITTING MAXIMUM ALL THICKNESS 3" NOTE: 0" CLEAANCE PEMISSIE AT EA OF FUNACE FO A IDTH OF 3" MAXIMUM ANCHO TO FLOO Figure 12 NT 24/30/34SP P30S GASKET: PEEL OFF POTECTIVE PAPE TO EXPOSE THE ADHESIVE SUFACE. ATTACH GASKET TO ASHE. PLACE ASHE OVE GAS FITTING. THE GASKET SHOULD SEAL AGAINST CABINET HEN GAS FITTING IS THEADED INTO POSITION. MAXIMUM ALL THICKNESS FO THIS UNIT IS 2 1/4" SEE FIGUE 4 IF MOE THAN 2 1/4" ALL THICKNESS. 2 3/4" DIA. TO HOLES. INTAKE TUBE Figure 13 NT 24/30/34SP P30 CAULK BEHIND VENT CAP AS SHON TO SEAL BETEEN EXHAUST AND INTAKE AND TO PEVENT MOISTUE INSIDE FUNACE COMPATMENT. APPL CAULKING GENEOUSL AOUND PEIMETE OF VENT CAP AND ACOSS CENTE AS SHON. CENTE PUTT STIP IS ESSENTIAL. ANCHO VENT ASSEM ITH THE SCE POVIDED. BE SUE SCE ENGAGES FUNACE EXHAUST TUBE AND IS PULLED SECUE. EXTENSION TUBE KIT NUMBE MIN./MAX. LENGTH (Extension Tube ange) /4 to 3 1/ /8 to 4 7/ /8 to to 9 EXTENSION TUBE KIT NUMBE Figure 14 NT 24/30/34SP P30 MIN./MAX. LENGTH (Extension Tube ange) /4 to 3 1/ /8 to 4 7/ /8 to to 9 Figure 15 NT 40 P40 16

17 VENT ASSEM INSTALLATION (NT40 & P40) * 3.50" FOM CENTE LINE OF INTAKE TO CENTE LINE OF EXHAUST ** 7.50" FOM CENTE LINE OF INTAKE TO FLOO HEAT SHIELD COLLA EXHAUST VENT CAP (2) 3.00" DIA. HOLES INSIDE ALL OUTSIDE SKIN 13 1/8 2 3/4 AI INTAKE FUNACE 12 7/16 6 7/32 3 1/2 * FLOO 7 1/2 * * SUBUBAN POE SUPPL IES MAXIMUM ALL THICKNESS 2.25" NOTE: 0" CLEAANCE PEMISSIE AT EA OF FUNACE FO A IDTH OF 2.25" MAXIMUM. GAS FITTING ANCHO TO FLOO Figure 16 NT40 * 3.50" FOM CENTE LINE OF INTAKE TO CENTE LINE OF EXHAUST ** 7.50" FOM CENTE LINE OF INTAKE TO FLOO HEAT SHIELD COLLA EXHAUST VENT CAP (2) 3.00" DIA. HOLES INSIDE ALL OUTSIDE SKIN 13 1/8 2 3/4 AI INTAKE FUNACE 12 7/16 6 7/32 3 1/2 * 7 1/2 * * FLOO SUBUBAN POE SUPPL IES THEMOSTAT IES MAXIMUM ALL THICKNESS 2.25" NOTE: 0" CLEAANCE PEMISSIE AT EA OF FUNACE FO A IDTH OF 2.25" MAXIMUM. GAS LINE SHUT-OFF ANCHO TO FLOO GAS LINE ELBO Figure 17 P40 17

18 VENT ASSEM INSTALLATION (NT40 & P40) * 3 1/2" X 7" CUTOUT THU COMBUSTIE CONSTUCTION * 3 1/2" MAXIMUM ALL THICKNESS FO THIS TPE INSTALLATION IS 2 1/4" 2 1/4" MAX. 3 1/2" CAULK BEHIND VENT CAP AS SHON TO SEAL BETEEN EXHAUST AND INTAKE AND TO PEVENT MOISTUE INSIDE FUNACE COMPATMENT. APPL CAULKING GENEOUSL AOUND PEIMETE OF VENT CAP AND ACOSS CENTE AS SHON. CENTE PUTT STIP IS ESSENTIAL. *7" 7 1/2" HEAT SHIELD COLLA ANING: COLLA MUST BE ATTACHED TO ASSUE SAFE OPEATION. DO NOT EMOVE COLLA. VENT CAP 2 3/4" 3" DIA. (2) HOLES (OUTE SKIN) EXHAUST TUBE INTAKE TUBE CENTELINE OF FUNACE INSTALLATION Figure 18 NT40 P40 VENT ASSEM INSTALLATION (DD SEIES) Note: Vent cap must be installed on DD Furnace when bench testing. Figure 19 18

19 ETUN AI The cabinet that the furnace may be installed in will have louvers or openings for the return air back to the furnace. hen the furnace is installed, it is imperative that the return air louvers on the furnace cabinet opening are not obstructed. Usually, these furnaces are installed under a counter, sofa or bed in order to be out of the way. A grille or opening must be built into the cabinetry or into the base area of the sofa or bed. eturn air from the living area of the trailer is drawn in through the grille and into the return air openings in the furnace cabinet. Figure 20 illustrates the return air circulation of the furnace. Note: efer to the installation manual for the minimum return air area for your specific furnace model. Insufficient return air will cause the furnace to overheat and cycle on limit. Another symptom of a return air problem is: 1. Furnace seems to run continuously in an effort to satisfy the thermostat. OPENING FO ETUN AI SPACE BUMPS SPACE BUMPS 0" TO SPACE OPENING FO ETUN AI FUNACE 0" TO SPACE MAINTAIN A 1/4" INCH CLEAANCE HEE DUCTS PASS THOUGH A CABINET ALL. UL LISTED DUCT MATEIALS CAN BE 0" CLEAANCE. THE TOTAL, FEE, UNOBSTUCTED ETUN AI OPENING TO THE FUNACE MUST NOT BE LESS THAN THE MINIMUM SPECIFIED. Figure 20 SF 20F/25F/35F/42F 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: (efer to the installation manual for the minimum ducted square inches area for each model.) 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. hen installing a duct system, avoid making a lot of turns. The straighter the duct system, the less the resistance to air flow and the better the performance of the furnace. Avoid making sharp turns in the duct system. Sharp turns will increase the static pressure in the plenum area of the furnace and could cause the furnace to cycle on limit. The duct connections to the furnace cabinet should be tight to eliminate any heat loss which could result in overheating of the component parts on the furnace as well as a reduction in the heated air flow through the duct work. Figure 21 19

20 ETUN AI & DUCTING INSTALLATION EQUIEMENTS MODELS CL FONT CL TOP CL BTM CL BACK CL LEFT CL IGHT DUCTS EQ D BTM DUCT SQ INCH TOP DUCT SQ INCH L & SIDE DUCT SQ INCH ETUN AI SQ INCH DD-17DSI SEE * N/A N/A N/A N/A N/A NT 12S 3/ N/A N/A NT 16S/N16SQ 3/ N/A N/A NT 20S/N20SQ N/A N/A NT 12SE SEE *1 5/ /8 5/8 N/A N/A N/A N/A N/A NT 16SE/SEQ SEE *1 5/ /8 5/8 N/A N/A N/A N/A N/A NT 20SE/SEQ SEE *1 5/ /8 5/8 N/A N/A N/A N/A N/A NT 24SP N/A NT 30SP N/A NT 34SP N/A NT N/A P N/A P N/A *1 - Special clearances for discharge grills. efer to Installation and Instruction Manual. *2 - eturn air should be 142 if 4 ducts are used. May be reduced to 88 if 5 ducts are used. NOTE: 0 clearance is to spacer (flanges) 20

21 ETUN AI & DUCTING INSTALLATION EQUIEMENTS MODELS CL FONT CL TOP CL BTM CL BACK CL LEFT CL IGHT DUCTS EQ D BTM DUCT SQ INCH TOP DUCT SQ INCH L & SIDE DUCT SQ INCH ETUN AI SQ INCH SF 20/20F SF 20Q/20FQ SF 25/25F SF 25Q/25FQ SF 30/30F SF 30Q/30FQ SF35/35F SF35Q/35FQ SF 42/42F SEE * SEE *2 SF 42Q/42FQ SEE * SEE *2 SH SH SEE * SEE *2 SHD SEE * SEE *2 *1 - Special clearances for discharge grills. efer to Installation and Instruction Manual. *2 - eturn air should be 142 if 4 ducts are used. May be reduced to 88 if 5 ducts are used. *3 - Bottom duct required. SF42/42Q uses KIT# , SH42 and SHD-2542 uses KIT# NOTE: 0 clearance is to spacer (flanges) *SF-42Q Bottom Duct requires use of Bottom Duct Kit, Part No **SF-20/25/30Q has two 4 round ducts available off of cabinet front. ***SF-35/42Q has three 4 round ducts available off of cabinet front.this front is not to be used on SF-20/25/30Q 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. 21

22 ETUN AI & DUCTING INSTALLATION EQUIEMENTS MODELS CL FONT CL TOP CL BTM CL BACK CL LEFT CL IGHT DUCTS EQ D BTM DUCT SQ INCH TOP DUCT SQ INCH L & SIDE DUCT SQ INCH ETUN AI SQ INCH SFV 20/20F SEE *4 52 SEE *4 SEE *4 55 SFV 25/25F SEE *4 52 SEE *4 SEE *4 55 SFV 30/30F SEE *4 52 SEE *4 SEE *4 55 SFV 35/35F SEE *4 52 SEE *4 SEE *4 55 SFV 42/42F SEE *4 52 SEE *4 SEE *4 142 *1 - Special clearances for discharge grills. efer to Installation and Instruction Manual. *2 - eturn air should be 142 if 4 ducts are used. May be reduced to 88 if 5 ducts are used. *3 - Bottom duct required. SF42/42Q uses KIT# , SH42 and SHD-2542 uses KIT# *4 - For Vertical mount furnace, review the table below for ducting requirements. The duct requirements must be followed in order to assure proper operation of the furnace. The minimum open duct areas listed below must be maintained through the entire duct system, including through register. NOTE: 0 clearance is to spacer (flanges) MODELS TOP AND FONT DUCTS (4 ound) BOTTOM LEFT DUCT IGHT DUCT Minimum Duct Area Minimum Duct Area Minimum Duct Area SFV 20/20F *Optional equired 52 SQ. IN. *Optional *Optional SFV 25/25F *Optional equired 52 SQ. IN. *Optional *Optional SFV 30/30F *Optional equired 52 SQ. IN. *Optional *Optional SFV 35/35F 48 SQ. IN. (Bottom Front Duct Not to be Used) 52 SQ. IN. 56 SQ. IN. DO NOT USE SFV 42/42F 48 SQ. IN. (Top Front Duct Not to be Used) 52 SQ. IN. 56 SQ. IN. 72 SQ. IN. *Use of these ducts are in addition to the required use of the bottom duct. ** hen using bottom duct on SFV-35Q/FQ and SFV-42Q/FQ, remove the discharge cover plate before installing. If bottom duct is NOT used of SFV-35Q/FQ and SFV-42Q/FQ, the discharge cover plate MUST remain in place. ***SFV-42Q/FQ Bottom Duct requires use of Bottom Duct Kit, Part No ****SFV-20/25/30Q/FQ has two 4 round ducts available off of cabinet front. *****SFV-35/42Q/FQ has three 4 round ducts available off of cabinet front.this front is not to be used on SFV-20/25/30Q NOTE: Ducts terminating in a dead air space (like holding tank compartments or cargo areas (Toy Boxes)) with no means for return air re-circulation 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. 22

23 ELECTICAL SUPPL INFOMATION CONNECTING ELECTICAL SUPPL 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. No. 12 gauge wire is recommended. If any of the original wire that is supplied with the appliance must be replaced, it must be replaced with type 105 C or its equivalent. Power supply connections are to be on the right side of the furnace. The wires are color coded, red for positive (+) and yellow for negative (-). This polarity must be observed so the furnace motor will run the proper direction of rotation to insure correct air delivery. (See wiring diagram.) If the furnace power supply is to be from a converter, we recommend that the converter system used to power the furnace be wired in parallel with the battery. This will serve two purposes: 1. Provide a constant voltage supply to the furnace. 2. Filter any A.C. spikes or volt surges. 23

24 FUNACE SPECIFICATIONS 12 VDC MODELS MODEL DESCIPTION INPUT BTU/hr GAS TPE VOLTAGE MOTO DIAMETE AMP DA STATIC PESSUE C.F.M. MAX. DD-17DSI Direct Discharge 17,000 POPANE 12 VDC N/A 145 NT 12S Ducted 12,000 POPANE 12 VDC C 122 NT 16S NT 16SQ Ducted 16,000 POPANE 12 VDC S 3.1 SQ.1 C 165 NT 20S NT 20SQ Ducted 19,000 POPANE 12 VDC S 3.1 SQ.1 C 165 NT 12SE Direct Discharge 12,000 POPANE 12 VDC N/A 140 NT 16SE NT 16SEQ Direct Discharge 16,000 POPANE 12 VDC SE 2.7 SEQ N/A 140 NT 20SE NT 20SEQ Direct Discharge 19,000 POPANE 12 VDC SE 2.7 SEQ N/A 150 NT 24SP Ducted 24,000 POPANE 12 VDC C 265 NT 30SP Ducted 30,000 POPANE 12 VDC C 345 NT 34SP Ducted 34,000 POPANE 12 VDC C 373 NT 40 Ducted 40,000 POPANE 12 VDC /.20B 441 PAK MODELS P 30S Ducted 30,000 POPANE 120 VAC C 345 P 40** Ducted 40,000 POPANE 120 VAC C 441 NOTE: ** P 40 Park Model Furnace and valve is convertible to Natural Gas. Instructions on converting unit to Natural Gas are on Sticker on side of cabinet. 24

25 FUNACE SPECIFICATIONS MODEL DESCIPTION INPUT BTU/hr 12 VDC MODELS GAS TPE VOLTAGE MOTO DIAMETE SF 20/20F Ducted 20,000 POPANE 12 VDC 3 SF 20Q/20FQ Ducted 20,000 POPANE 12 VDC 3 SF 25/25F Ducted 25,000 POPANE 12 VDC 3 SF 25Q/25FQ Ducted 25,000 POPANE 12 VDC 3 SF 30/30F Ducted 30,000 POPANE 12 VDC 3 SF 30Q/30FQ Ducted 30,000 POPANE 12 VDC 3 SF35/35F Ducted 35,000 POPANE 12 VDC 3 SF35Q/35FQ Ducted 35,000 POPANE 12 VDC 3 AMP DA 6.5=2.5 IN. MOTO 8.5=3 IN 7.0=3 IN. MOTO 6.5=2.5 IN. MOTO 8.5=3 IN 7.0=3 IN. MOTO 6.5=2.5 IN. MOTO 8.5=3 IN 7.0=3 IN. MOTO IN. MOTO 9.4=3 IN 8.0=3 IN. MOTO STATIC PESSUE C.F.M. MAX..2 C C C C C C C C 375 SF 42/42F Ducted 40,000 POPANE 12 VDC C 430 SF 42Q/42FQ Ducted 40,000 POPANE 12 VDC C 430 SFV 20/20F Ducted 20,000 POPANE 12 VDC C 300 SFV 25/25F Ducted 25,000 POPANE 12 VDC C 300 SFV 30/30F Ducted 30,000 POPANE 12 VDC C 300 SFV 35/35F Ducted 35,000 POPANE 12 VDC C 375 SFV 42/42F Ducted 40,000 POPANE 12 VDC C 430 SH 35/35F Ducted 35,000 POPANE 12 VDC C 375??? SH 42/42F Ducted 40,000 POPANE 12 VDC C 430 SHD 2542 Ducted 25,000 40,000 POPANE 12 VDC (LO) 12 (HIGH).25 C

26 SEQUENCE OF OPEATION FO 12VDC FAN CONTOL MODULE BOAD TIME LINE Start Time Thermostat Calls for Heat DESCIPTION 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. The module board constantly checks for a minimum 9.5 volts. If there is not 9.5 volts, the module board will go into a stand by mode until adequate power is supplied. It will then resume normal operation. Upon a call from the thermostat, the module board thermostat circuit will go active. The sail switch circuit is verified as being open. The blower output is energized. Blower motor starts. The module board will then verify that the sail switch circuit is closed and motor is up to speed. If this circuit remains open for 30 seconds after the blower motor starts, the module board will go into lockout mode and shut down the blower motor. 15 Seconds Purge Cycle The module board checks that the gas valve relay contacts (which are located on the module board) are open before the ignition sequence starts. The board has a pre-purge timing circuit of approximately 15 seconds. This allows the combustion chamber to purge. The module board will energize the gas valve and enable the high voltage spark output to the electrode for seven (7) seconds of ignition time. 7 Seconds Ignition Cycle and Flame Sense The module board will then check for flame sense to verify successful lighting of the main burner flame. Sparking of the igniter will then be terminated and the gas valve and blower outputs will remain energized. If ignition is successful the module board will monitor the flame sense, sail switch and limit switch circuits, and the thermostat inputs during the heating period. The flame is sensed through the spark wire and electrode. Therefore, it is essential that the electrode is properly positioned in the burner flame. 3 Try Ignition Board 2nd and 3rd Ignition Cycles if equired Heating Cycle If the flame is not sensed after seven (7) seconds, a second 15 second purge cycle will begin followed by a second Trial-For-Ignition sequence. After three (3) Trial-For-Ignition attempts with no ignition of the main burner, the module board will de-energize the gas valve immediately and blower will run for 3 minutes and then shutdown in lockout mode. If during the heating cycle, the limit switch circuit opens and remains open for 5 minutes, the module board will go into lock out and shut down the blower motor. If this occurs, the thermostat will need to be reset for the furnace to operate. 90 Second Shut Down hen the thermostat has reached its set point and the demand for heat ends, the gas valve will be de-energized and the flame will go out. The post purge period of 90 seconds begins. hen it times out, the blower motor output is removed, and the blower stops. 26

27 SEQUENCE OF OPEATION FO 24 VAC FAN CONTOL MODULE BOAD PAT NUMBE TIME LINE Start Time DESCIPTION 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. The module board constantly checks for a minimum 18 volts for normal operation. Thermostat Calls for Heat Upon a call from the thermostat, the module board thermostat circuit will go active. The sail switch circuit is verified as being open. The blower output is energized. Blower motor starts. The module board will then verify that the sail switch circuit is closed and motor is up to speed. If this circuit remains open, blower motor will run continuously until sail switch closes 15 Seconds Purge Cycle The module board checks that the gas valve relay contacts (which are located on the module board) are open before the ignition sequence starts. The board has a pre-purge timing circuit of approximately 15 seconds. This allows the combustion chamber to purge. The module board will energize the gas valve and enable the high voltage spark output to the electrode for 7 seconds of ignition time. 7 Seconds Ignition Cycle and Flame Sense The module board will then check for flame sense to verify successful lighting of the main burner flame. Sparking of the igniter will then be terminated and the gas valve and blower outputs will remain energized. If ignition is successful the module board will monitor the flame sense, sail switch and limit switch circuits, and the thermostat inputs during the heating period. The flame is sensed through the spark wire and electrode. Therefore, it is essential that the electrode is properly positioned in the burner flame. 3 Try Ignition Board 2nd and 3rd Ignition Cycles if equired Heating Cycle If the flame is not sensed after seven (7) seconds, a second 15 second purge cycle will begin followed by a second Trial-For-Ignition sequence. After three (3) Trial-For-Ignition attempts with no ignition of the main burner, the module board will de-energize the gas valve immediately and blower will run for 3 minutes and then shutdown in lockout mode. If during the heating cycle, the limit switch circuit opens and remains open, the gas valve will close and the blower motor will continue to run. 90 Second Shut Down hen the thermostat has reached its set point and the demand for heat ends, the gas valve will be de-energized and the flame will go out. The post purge period of 90 seconds begins. hen it times out, the blower motor output is removed, and the blower stops. 27

28 SEQUENCE OF OPEATION FO SHD-2542 TIME LINE Start Time Thermostat Calls for Heat DESCIPTION 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. The module board constantly checks for a minimum 9.5 volts. If there is not 9.5 volts, the module board will go into a stand by mode until adequate power is supplied. It will then resume normal operation. Upon a call from the thermostat, the First Stage will be activated (NOTE: Could be Second Stage if 1 & 2 powered). The module board thermostat circuit will go active and the sail switch circuit is verified as being open. The blower output is energized. Blower motor starts. The module board will then verify that the sail switch circuit is closed and motor is up to speed. If this circuit remains open for 30 seconds after the blower motor starts, the module board will go into lockout mode and shut down the blower motor. 15 Seconds Purge Cycle The module board checks that the gas valve relay contacts (which are located on the module board) are open before the ignition sequence starts. The board has a pre-purge timing circuit of approximately 15 seconds. This allows the combustion chamber to purge. The module board will energize the gas valve and enable the high voltage spark output to the electrode for 7 seconds of ignition time. 7 Seconds Ignition Cycle and Flame Sense The module board will then check for flame sense to verify successful lighting of the main burner flame. Sparking of the igniter will then be terminated and the gas valve and blower outputs will remain energized. If ignition is successful the module board will monitor the flame sense, sail switch and the limit switch circuits, and the thermostat inputs during the heating period. The flame is sensed through the spark wire and electrode. Therefore, it is essential that the electrode is properly positioned in the burner flame. 3 Try Ignition Board 2nd and 3rd Ignition Cycles if equired 2nd Stage Heating Cycle 90 Second Shut Down If the flame is not sensed after seven (7) seconds, or if the unit fails to ignite, a second fifteen (15) second purge cycle will begin followed by a second Trial-For-Ignition sequence. After three (3) Trial-For-Ignition attempts with no ignition of the main burner, the module board will deenergize the gas valve immediately and blower will run for three (3) minutes and then shutdown in lockout mode. If during the thermostat cycle, the demand for heat drops below the second stage thermostat setting (3 to 5 degrees variance depending on thermostat manufacturer), the blower speed control board will be energized. The blower speed control board will energize the additional gas valve solenoid and increase motor speed to the high position. Furnace will remain in the second stage operation until thermostat is satisfied. hen the thermostat has reached its set point and the demand for heat ends, the gas valve will be de-energized and the flame will go out. The post purge period of 90 seconds begins. hen it times out, the blower motor output is removed, and the blower stops. 28

29 SEQUENCE OF OPEATION FO FUNACES EQUIPPED ITH TIME DELA TIME LINE Start Time Thermostat Calls for Heat DESCIPTION 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. The relay receives the power and allows power to pass through to the switch within the relay. This is done by a heater coil within the relay which actuates a bi-metal disc closing the relay circuit. The module board thermostat circuit will go active. The sail switch circuit is verified as being open. The blower output is energized. Blower motor starts. 15 Second Purge Cycle The limit switch protects the furnace from over heating conditions. The contacts in the limit switch open at a given temperature setting, shutting off power to the ignition system which controls the gas valve. As the room air wheel comes up to speed, air flow closes the sail switch completing the circuit. The sail switch is placed into the system as a safety to prove there is adequate air for combustion. The next operation is controlled by the Direct Spark Ignition (DSI) system as power is applied to the DSI Board. The system will do the following: 7 Seconds Ignition Cycle and Flame Sense 1. The board has a timing circuit which allows the blower to purge the chamber of any products of combustion or gas. 2. The board will then apply power to the gas valve. At the same time it produces a high voltage power supply to the electrode producing spark at the burner. 3. The board will also confirm the presence of a flame. If the flame is not sensed after seven (7) seconds, the module will try two (2) more times and then go into lock out mode. The flame is sensed through the spark at the burner. 2 & 3 Ignition Cycles If Needed If the flame is not sensed after seven (7) seconds, a second 15 second purge cycle will begin followed by a second Trial-For-Ignition sequence. After three (3) Trial-For-Ignition attempts with no ignition of the main burner, the module board will de-energize the gas valve immediately and blower motor will continue to operate. Heating Cycle If during the heating cycle, the limit switch circuit opens and remains open, the gas valve will close and the blower motor will continue to run. 90 Second Shut Down hen the thermostat has reached its set point and the demand for heat ends, the gas valve will be de-energized and the flame will go out. The post purge period of 90 seconds begins. hen it times out, the blower motor output is removed, and the blower stops. NOTE: On some models, Sail Switch is before limit switch. 29

30 Thermostat Closes ES TOUE SHOOTING GUIDE SUBUBAN V FUNACES with TIME DELA 12 VDC HEATING SECTION - NO Check thermostat wire connections, contact points and the heat anticipator. No Check 12VDC at UE wire, check the amp draw to the thermostat. No Check for shorts. Check components amperage. ES 30 - ES Clean points, secure loose connections, replace thermostat if anticipator is shorted. - ES eplace Thermostat. - ES epair or replace connection or parts with higher than normal amp draw. Check for 12VDC at Furnace - NO Check ON/OFF Switch on Furnace ES Check fuse or circuit breaker - NO eplace fuse/eset Breaker Approximately seconds Blower is operating - NO ES Check for 12VDC at time delay relay and for 12VDC to ED wire leading to the motor. ES - NO eplace the Time Delay elay ES Check GOUND wire on terminal block - NO eplace the motor After fifteen (15) seconds the module creates spark and opens valve ES Spark occurs for approximately seven (7) seconds and main burner flame establishes - NO Check for 12VDC between ED and ELLO wires at the module board No Check for 12VDC at Limit Switch, on both sides No Check for 12VDC at Sail Switch, on both sides - ES Check plug connection tot he Module- Electrode and ire-spark gap 1/8 between probe and ground - ES eplace the Sail Switch - ES eplace the Limit Switch - NO No Spark at the Electrode - NO eplace the Module ES Check for 12VDC at Gas Solenoid Valve Did the Gas Valve open? - NO ES ES ES Check for restriction in combustion air intake (wasps, insects, etc.) Is flame established? - NO Thermostat opens and the time delay operates the fan for the cool down cycle ES SSTEM OK No - NO eplace the Time Delay elay - NO eplace the Module Check gas pressure at the manifold or for restrictions in the burner orifice No eplace the gas valve Check flame contact to electrode. Flame should be hard blue NOTE: On some models, Sail Switch is before Limit Switch