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Thermal Zone
Furnace

Model # GM120K20C Official Thermal Zone gas furnace

Here are the diagrams and repair parts for Official Thermal Zone GM120K20C gas furnace, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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ALL PARTS
Showing 10 of 33 parts  |
Capacitor 621435
#22

80+ upflow furnace diagram

Capacitor

Part #621435

Replaced by #12908

?
Manufacturer substitution
This part replaces 621435. Substitute parts can look different from the original.
This item is not returnable
$5.26 | 
16% OFF Phone Price : $6.26
In Stock
Furnace Electronic Control Board 903106
#25

80+ upflow furnace diagram

Furnace electronic control board

Part #903106

$297.66
In Stock
Furnace Control Module Assembly 903108
#25A

80+ upflow furnace diagram

Furnace control module assembly

Part #903108

The manufacturer no longer makes this part, and there's no substitute part

Furnace Blower Wheel 667277
#20

80+ upflow furnace diagram

Furnace blower wheel

Part #667277

The manufacturer no longer makes this part, and there's no substitute part

Furnace Blower Fan Motor Assembly 902816
#23

80+ upflow furnace diagram

Furnace blower fan motor assembly

Part #902816

The manufacturer no longer makes this part, and there's no substitute part

Transformer 621486
#24

80+ upflow furnace diagram

Transformer

Part #621486

The manufacturer no longer makes this part, and there's no substitute part

Sensor Rod 632316
#6

80+ upflow furnace diagram

Sensor rod

Part #632316

The manufacturer no longer makes this part, and there's no substitute part

Switch 632212
#17

80+ upflow furnace diagram

Switch

Part #632212

The manufacturer no longer makes this part, and there's no substitute part

Furnace Burner Flame Roll-out Switch 626343
#7

80+ upflow furnace diagram

Furnace burner flame roll-out switch

Part #626343

The manufacturer no longer makes this part, and there's no substitute part

Gas Valve 624586
#2

80+ upflow furnace diagram

Gas valve

Part #624586

The manufacturer no longer makes this part, and there's no substitute part

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