ICP Defrost Control Board for YK018G1 — Heat Pump | Ships Today

Overview

This genuine OEM defrost control board (part #34332101) for the ICP/Tempstar/Heil YK018G1 heat pump manages the unit's defrost cycle. In heating mode, frost builds on the outdoor coil; the defrost board monitors coil temperature and elapsed time, then commands the reversing valve and auxiliary heat to melt the ice before returning to normal operation. The board also coordinates the contactor and fan during defrost. When it fails, the heat pump may ice over completely, run inefficiently, short-cycle, or fail to switch modes — driving up energy bills and reducing heating output. This board is a direct OEM replacement built to factory specifications for reliable, correctly-timed defrost cycles.

Specifications

Compatibility

Direct OEM replacement for the ICP/Tempstar/Heil YK018G1 heat pump and other units using defrost board part #34332101. Confirm the board's part number and connector layout against your existing board before ordering.

Installation Guide

1. Safety First — Disconnect power at the disconnect and breaker, and verify zero voltage with a multimeter.
2. Access — Remove the condenser control-box panel to reach the board.
3. Document — Photograph all wire harnesses, plugs, and the defrost timer pin setting before disconnecting.
4. Remove — Unplug each connector, release the standoffs/screws, and lift the old board out.
5. Install — Mount the new board, set the defrost timer pins to match the original, and reconnect every harness per your photo.
6. Test — Restore power, run a heating cycle, and confirm proper defrost initiation and termination.

Signs You Need a Replacement

• Outdoor coil ices over and never defrosts.
• Heat pump short-cycles or won't switch between heat and cool.
• Defrost runs too often or never terminates.
• No 24V output to the reversing valve or contactor during defrost.

Shipping & Returns

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