The Excalibur 8520-III service diagram identifies the original revision III blower, combustion and ignition items and gas valves. Some parts differ by serial number, so the full model designation matters.
Select a linked manufacturer number for product details and availability. Match the full furnace model and serial number, including any supersession or discontinued-part notes.
8520-III service part references
| Reference | Manufacturer part number | Quantity | Component description |
|---|---|---|---|
| 1 | 36170 | 1 | BLOWER WHEEL USE 37764 |
| 1 | 37764 | 1 | BLOWER WHEEL USE 33126 |
| 1 | 33126 | 1 | BLOWER WHEEL KIT |
| 2 | 33580 | 1 | BLOWER HOUSING COVER |
| 3 | 36178 | 1 | BLOWER HOUSING ASSEMBLY |
| 4 | 36332 | 1 | PLATE & GASKET ASSY |
| 5 | 33647 | 1 | BURNER BOX ASSY |
| 6 | 33842 | 1 | BURNER - NLA |
| 7 | 33165 | 1 | EXTENSION BOX KIT |
| 8 | 35791 | 1 | HYDRO FLAME 5AMP BREAKER |
| 8 | 32331 | 1 | 7AMP CIRCUIT BREAKER USE 33751 |
| 8 | 33751 | 1 | CIRCUIT BREAKER 7-AMP |
| 9 | 33475 | 1 | REPLACEMENT VALVE COIL - DC USE 31000 |
| 9 | 31000 | 1 | COIL, WHITE ROGERS DC |
| 10 | 37107 | 1 | COMBUSTION WHEEL USE 33128 |
| 10 | 33128 | 1 | COMBUSTION AIR WHEEL |
| 11 | 36175 | 1 | CONTROL BOX ASSY |
| 12 | 33620 | 1 | INNER DOOR HINGE - 1PR |
| 13 | 33754 | 1 | DOOR ASSY, DELUXE, 02, COLONIAL WHITE |
| 13 | 33756 | 1 | DOOR ASSY, DELUXE, 04, POLAR WHITE |
| 13 | 33764 | 1 | EXCALIBUR DOOR, BEIGE |
| 13 | 34517 | 1 | EXCALIBUR DOOR, GREY |
| 14 | 33729 | 1 | SLIDE PLATE - NLA - BEFORE S/N 0654748 |
| 14 | 37411 | 1 | SLIDE PLATE - AFTER S/N 0654747 |
| 15 | 31030 | 1 | T-STAT - BEIGE USE 38452 |
| 15 | 38452 | 1 | T-STAT HEAT ONLY - BROWN |
| 15 | 38453 | 1 | THERMOSTAT HEAT ONLY - WHITE |
| 16 | 33586 | 1 | VALVE BRACKET |
| 17 | 33337 | 1 | WHITE ROGERS VALVE USE 38607 - BEFORE S/N 0654748 |
| 17 | 38607 | 1 | GAS VALVE USE 31155 - BEFORE S/N 0654748 |
| 17 | 31155 | 1 | KIT, VALVE STRAIGHT, 12VDC WHITE-RODGERS - BEFORE S/N 0654748 |
| 17 | 37383 | 1 | GAS VALVE, SIDE OUTLET USE 31150 - AFTER S/N 0651155 |
| 17 | 38604 | 1 | WHITE ROGERS VALVE USE 31150 - AFTER S/N 0654748 |
| 17 | 31150 | 1 | GAS VALVE, SIDE OUTLET, 12 VDC COIL - WHITE-ROGERS - AFTER S/N 0654748 |
| 18 | 36180 | 1 | WIRING HARNESS ASSY |
| 18 | 36290 | 1 | FIELD PLUG ASSEMBLY |
Replacement parts shown in the diagram
These listings match manufacturer numbers linked in the parts table. Check the complete furnace model, serial number and version of each component before ordering. View product pages for current availability.
Diagram ref 1 · MPN 33126
Atwood 33126 Furnace Blower Wheel with Clamp - 8500 Series
View product and availability