ICP Defrost Control Board for WCH3242GKA1 — OEM 1173636 Heat Pump | Ships Today

Overview

This OEM defrost control board (part #1173636) is the electronic brain of the ICP / Heil / Tempstar WCH3242GKA1 heat pump. It manages the outdoor unit's defrost cycle, monitoring coil temperature and accumulated run time to decide when frost on the outdoor coil must be cleared. When a defrost is needed, the board sequences the reversing valve, shuts down the outdoor fan, and brings on auxiliary heat so the indoor space stays comfortable while the coil thaws. It operates on a 24V control circuit and coordinates the defrost thermostat, time-temperature logic, and safety interlocks. A failed defrost board is a common cause of heat-pump no-heat calls: the unit may become stuck in defrost, ice over solidly in cold weather, fail to switch the reversing valve, or run constantly on expensive emergency heat. Installing the correct OEM board restores reliable, efficient heating performance.

Specifications

Compatibility

Engineered for the ICP / Heil / Tempstar WCH3242GKA1 heat pump and matching WCH-series condensing units that use the 1173636 defrost board. Compatible across the family of brands built on the same platform, including Comfortmaker and Arcoaire variants. Always confirm the part number printed on your existing board before ordering.

Installation Guide

1. Safety First — Disconnect power at the outdoor disconnect and the breaker, then verify zero voltage with a multimeter before touching any wiring.
2. Access — Remove the outdoor unit control-panel access cover to expose the board.
3. Document — Photograph every wire connection on the old board before disconnecting anything.
4. Remove — Label and unplug the harness connectors, release the board mounting clips or screws, and lift out the old defrost board.
5. Install — Mount the new 1173636 board, then reconnect each terminal and connector exactly as shown in your photo.
6. Test — Restore power and run a heating cycle; initiate a forced defrost to confirm the reversing valve, fan shutdown, and timing all function.

Signs You Need a Replacement

• Outdoor coil ices over and the unit never defrosts
• Heat pump stuck in defrost or constantly switching modes
• No heat-pump heating and the system defaults to emergency/auxiliary heat
• Reversing valve fails to energize during a defrost cycle

Shipping & Returns

Ships same day on orders placed before 3 PM CST. 30-day hassle-free returns. Backed by the National HVAC Parts fitment guarantee.