ICP Defrost Control Board for YJ042G1 — Heat Pump Timer Board | Ships Today

Overview

This OEM defrost control board (ICP part number 34332101) is the brain of the defrost cycle on your ICP/Tempstar/Heil YJ042G1 heat pump. During heating season, frost accumulates on the outdoor coil; this board monitors coil temperature and elapsed run time, then commands a defrost cycle to reverse the refrigerant flow and melt the ice. When the board fails, the unit may ice over completely, fail to switch out of defrost, short-cycle, or stop heating altogether. A 24V-controlled circuit board, it coordinates the reversing valve, compressor, and outdoor fan timing during defrost.

Specifications

Compatibility

Engineered as a direct OEM replacement for the ICP/Tempstar/Heil YJ042G1 heat pump and equivalent units across the ICP family (Comfortmaker, Arcoaire). Always confirm the part number printed on your existing board matches 34332101 before installing.

Installation Guide

1. Safety First — Disconnect power at the disconnect and breaker, then verify zero voltage with a multimeter.
2. Access — Remove the outdoor unit's control-panel service cover.
3. Document — Photograph every wire and terminal position on the old board before disconnecting.
4. Remove — Label and unplug each connector, release the standoff clips or screws, and lift out the failed board.
5. Install — Mount the new board on the standoffs and reconnect every wire exactly per your photo.
6. Test — Restore power and run a heating/defrost cycle to confirm proper operation.

Signs You Need a Replacement

• Outdoor coil ices over and unit never defrosts
• Unit stuck in defrost or blowing cold air in heat mode
• Compressor or reversing valve not energizing on schedule
• No 24V output to defrost components

Shipping & Returns

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