Tempstar Defrost Control Board for T4H360GKA200 — Heat Pump Defrost Timer | Ships Today

Overview

This is the OEM defrost control board (Part #1173636) for the Tempstar T4H360GKA200 heat pump. The defrost control board is the brain of the heat pump's defrost cycle — it monitors outdoor coil temperature and run time, then commands the unit into defrost mode to melt frost off the outdoor coil during heating season. When this board fails, the system can ice over, lose heating capacity, short-cycle, or fail to reverse out of defrost. A faulty board often shows up as a unit that ices solid in cold weather or one that never initiates defrost at all.

Specifications

Compatibility

Direct OEM replacement for the Tempstar/Heil/ICP T4H360GKA200 heat pump. This board is shared across many ICP-family condensing units of the same generation, but always verify the printed part number (1173636) against your existing board before installing.

Installation Guide

1. Safety First — Disconnect power at the breaker and disconnect, and verify zero voltage with a multimeter before touching the board.
2. Access — Remove the outdoor unit's control-panel service cover.
3. Document — Photograph every wire and terminal position before disconnecting anything.
4. Remove — Label and unplug the low-voltage harnesses, sensor leads, and defrost thermostat connections, then unscrew the old board from its standoffs.
5. Install — Mount the new 1173636 board, reconnect each wire exactly per your photos, and set the defrost timing jumper/pins to match the original.
6. Test — Restore power and confirm normal heat-pump operation and a forced or timed defrost cycle.

Signs You Need a Replacement

• Outdoor coil ices over and never clears during heating mode.
• Unit never enters defrost, or stays stuck in defrost.
• No 24V output to the reversing valve or defrost relay.
• Visible burn marks, corrosion, or a cracked board.

Shipping & Returns

Ships same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.