ICP Defrost Control Board for WCH5604GKA100 — Heat Pump | Ships Today

Overview

This OEM defrost control board (part number 1173636) is the brains of the defrost cycle on your ICP WCH5604GKA100 heat pump. It monitors the coil temperature sensor and run time, then commands the reversing valve and auxiliary heat to clear frost from the outdoor coil during cold-weather heating. When the board fails, the heat pump can ice over, skip defrost entirely, lock into defrost continuously, or fail to energize the compressor and fan. Because it coordinates the 24V control circuit, a faulty board often mimics multiple other failures — replacing it restores correct defrost timing and full heating performance.

Specifications

Compatibility

Direct OEM replacement for the ICP/Tempstar/Heil WCH5604GKA100 heat pump condensing unit and other models using the same defrost board platform. Verify the board part number and connector layout against your existing unit.

Installation Guide

1. Safety First — Disconnect power at the disconnect and breaker, then verify zero voltage with a multimeter.
2. Access — Remove the condenser control panel to expose the board.
3. Document — Photograph every harness, jumper, and sensor connection before unplugging.
4. Remove — Unplug the connectors, release the standoffs or screws, and lift out the old board.
5. Install — Mount the new board, set any defrost-time jumper to match the original, and reconnect each harness per your photo.
6. Test — Restore power, run a heat call, and confirm normal operation and a forced defrost cycle.

Signs You Need a Replacement

• Outdoor coil ices up and never defrosts
• Unit stuck running a continuous defrost cycle
• No compressor or fan output despite a valid call
• Erratic reversing valve behavior or weak heating

Shipping & Returns

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