OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
This genuine OEM defrost control board (part 1173636) is the brain of the Tempstar T4H442GKA100 heat pump's defrost system. It monitors coil temperature and run time, then initiates and terminates defrost cycles to clear frost from the outdoor coil in heating mode. The board coordinates the reversing valve, condenser fan, and auxiliary heat during defrost. When it fails, the heat pump may ice over in winter, run continuous or no defrost cycles, short cycle, or fail to switch modes. This OEM board restores correct defrost timing and reliable cold-weather heating.
| Spec | Value |
|---|---|
| Part Number | 1173636 |
| Type | Defrost Control Board |
| Brand | Tempstar |
| Function | Defrost timing, reversing valve & fan control |
| Application | Heat Pump Outdoor Unit |
Built for the Tempstar T4H442GKA100 heat pump and related ICP/Heil family units specifying OEM part 1173636. Match the board's connector layout and part number to your original before installing.
Ships same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.