Tempstar Defrost Control Board for T4H436GKB100 — OEM 1173636 Heat Pump Board | Ships Today
OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
Overview
This genuine OEM defrost control board (part number 1173636) manages the defrost cycle on your Tempstar T4H436GKB100 heat pump. In cold weather, frost builds on the outdoor coil and chokes heating capacity. The defrost board monitors coil temperature and accumulated run time, then triggers a defrost cycle that reverses refrigerant flow and brings on auxiliary heat to melt the ice. A failed board causes the coil to ice over, the unit to stop heating, short-cycle, or defrost endlessly. It is one of the most common winter heat-pump failure points.
Specifications
| Spec | Value |
|---|---|
| Part Number | 1173636 |
| Type | Defrost Control Board |
| Brand | Tempstar (ICP / Heil) |
| Control Voltage | 24V |
| Application | Heat Pump Defrost Control |
| Fitment | OEM Replacement |
Compatibility
Engineered as a direct OEM replacement for the Tempstar T4H436GKB100 heat pump. The same 1173636 board is used across multiple ICP-family heat pumps (Tempstar, Heil, Comfortmaker, Arcoaire) — confirm the part number matches the board currently installed before ordering.
Installation Guide
- Safety First — Disconnect power at the outdoor disconnect and breaker. Verify zero voltage with a multimeter before handling wiring.
- Access — Remove the outdoor unit's control-panel service cover.
- Document — Photograph every wire and terminal position before disconnecting.
- Remove — Label and disconnect the low-voltage and sensor leads, release the mounting standoffs or screws, and lift out the old board.
- Install — Mount the new 1173636 board, reconnect each lead to its matching terminal per your photo, and seat the defrost sensor.
- Test — Restore power and run a test defrost (jumper the speed-up pins per the wiring diagram) to confirm the reversing valve and aux heat energize.
Signs You Need a Replacement
- Outdoor coil ices over and never clears
- Defrost cycle runs constantly or at incorrect intervals
- No heat output or frequent short-cycling in cold weather
- Reversing valve or auxiliary heat won't energize on a defrost call
Shipping & Returns
Ships same day on orders placed before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.
Shipping Information
- Orders placed before 3PM CST ship same business day
- Standard delivery: 2-5 business days
- Express shipping available at checkout
- Free shipping on orders over $75
- Tracking number emailed upon shipment
Return Policy
- 30-day returns on unused parts in original packaging
- Electrical parts (capacitors, contactors, control boards) are final sale once installed
- Email info@nationalhvacparts.com to initiate a return
- Refunds processed within 5-7 business days