ICP Defrost Control Board for YD036GA Heat Pump — OEM 34330100 | Ships Today

Overview

The ICP defrost control board (OEM part 34330100) is the brain of the defrost cycle on your YD036GA heat pump. It monitors outdoor coil temperature and accumulated run time, then commands the reversing valve and auxiliary heat to clear frost from the outdoor coil during cold-weather operation. When this board fails, the unit can ice over, lock out, run the compressor with no defrost, or refuse to switch between heating and cooling. It operates on a 24V control signal and interfaces with the defrost thermostat, reversing valve solenoid, and contactor.

Specifications

Compatibility

Engineered as a direct OEM replacement for the ICP/Tempstar/Heil YD036GA heat pump and other units in the same family that originally shipped with board 34330100. Always match your existing board's part number before ordering.

Installation Guide

1. Safety First — Disconnect power at the disconnect and breaker, then verify zero voltage with a multimeter.
2. Access — Remove the control panel cover from the outdoor unit.
3. Document — Photograph every wire and terminal on the old board before disconnecting.
4. Remove — Label and unplug the low-voltage connectors, release the mounting standoffs/screws, and lift out the failed board.
5. Install — Seat the new board on the standoffs and reconnect each wire exactly per your photo.
6. Test — Restore power and confirm the unit completes a normal heating cycle and initiates defrost on demand.

Signs You Need a Replacement

• Outdoor coil ices over and never defrosts
• Heat pump won't switch between heating and cooling
• Auxiliary/emergency heat runs constantly
• No 24V output to the reversing valve or contactor

Shipping & Returns

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