
FURNACES TABLE OF CONTENTS
RECOMMENDED TOOLS AND EQUIPMENT..........................................................................................4
AFS SERIES MODEL IDENTIFICATION ..................................................................................................5
REQUIRED DUCTING........................................................................................................................................................... 5
DISCHARGE AND DUCTING ............................................................................................................................................... 6
AFS Wiring............................................................................................................................................................................ 6
AFM SERIES MODEL IDENTIFICATION..................................................................................................7
REQUIRED DUCTING........................................................................................................................................................... 7
REQUIRED DISCHARGE ..................................................................................................................................................... 7
AFM Wiring ........................................................................................................................................................................... 8
AFL SERIES MODEL IDENTIFICATION ..................................................................................................9
REQUIRED DUCTING........................................................................................................................................................... 9
REQUIRED DISCHARGE ................................................................................................................................................... 10
AFL Wiring .......................................................................................................................................................................... 10
79 / 80 SERIES MODEL IDENTIFICATION ............................................................................................12
DUCTING CONFIGURATIONS........................................................................................................................................... 13
79 / 80 SERIES Directionnel Louver Insert (PN 36959) .................................................................................................. 13
Wiring Diagrams 7900 & 8012 Models ............................................................................................................................. 13
8500 SERIES Model Identification .................................................................................................................................... 15
Wiring Diagrams 8500 Models .......................................................................................................................................... 16
8900 SERIES MODEL IDENTIFICATION ...............................................................................................20
Wiring Diagrams 8900 Models .......................................................................................................................................... 20
85 / 89 2-STAGE SERIES MODEL IDENTIFICATION............................................................................23
Wiring Diagrams 2-Stage Models ..................................................................................................................................... 24
Fig 1 2-STAGE with Field Plug.......................................................................................................................................... 24
Fig 2 2-STAGE without Field Plug .................................................................................................................................... 24
MODEL HFH 2000 BI METAL THERMOSTAT .......................................................................................25
INSTALLATION & OPERATION......................................................................................................................................... 25
DIGITAL THERMOSTAT MODEL 1H2C.................................................................................................27
Specifications..................................................................................................................................................................... 27
WIRING REQUIREMENTS FOR ATWOOD THERMOSTAT ............................................................................................. 28
DIGITAL THERMOSTAT MODEL 2H2C TWO STAGE ..........................................................................29
Specifications..................................................................................................................................................................... 29
WIRING REQUIREMENTS FOR ATWOOD (ONLY) TWO STAGE THERMOSTAT......................................................... 29
SEQUENCE OF OPERATION –DC MODELS (STANDARD UNITS) ....................................................30
SEQUENCE OF OPERATION –DC MODELS (2- STAGE EXCALIBUR™ FURNACES ONLY) ..........32
SEQUENCE OF OPERATION –PILOT MODELS..................................................................................33
SEQUENCE OF OPERATION –AC MODELS .......................................................................................34
CRITICAL INSTALLATION CRITERIA ...................................................................................................35
ANNUAL PREVENTATIVE MAINTENANCE INSPECTION ...................................................................35
MECHANICAL THERMOSTAT ...............................................................................................................36
CIRCUIT BREAKER & MOTOR..............................................................................................................37
CIRCUIT BOARDS..................................................................................................................................38
RELAY.....................................................................................................................................................38
SAIL SWITCH..........................................................................................................................................39
LIMIT SWITCH ........................................................................................................................................39
DUAL SOLENOID GAS VALVE..............................................................................................................39
BURNER HEAD, ELECTRODE AND VALVE ASSEMBLY ....................................................................40
#4- RETURN AIR.....................................................................................................................................42
TROUBLE SHOOTING GUIDES.............................................................................................................42
Mechanical Thermostat ..................................................................................................................................................... 42
Furnace –Electronic Ignition Models .............................................................................................................................. 43
Furnace –Electronic Ignition Models (continued) ......................................................................................................... 44
Furnace –Electronic Ignition Models (continued) ......................................................................................................... 45
FURNACE TERMINOLOGY................................................................................................................................................ 46
FLAT RATE SCHEDULE ........................................................................................................................48
8500-IV LD & 2-STAGE SERIES FURNACE PARTS.............................................................................62
8900-IV DC & AC - LD & 2-STAGE SERIES FURNACE ARTS .............................................................67
WARRANTY ............................................................................................................................................71
FURNACE EXTENDED SERVICE CONTRACT .....................................................................................71
TERM AND PROVISIONS: ................................................................................................................................................. 71
EXCLUSIONS (SPECIFICALLY EXCLUDED FROM THE WARRANTIES) ..................................................................... 71
LIMITATIONS ...................................................................................................................................................................... 71