ICP Defrost Control Board for YC048F — 24V Heat Pump | Ships Today

Overview

This is the genuine OEM defrost control board (part number 34332100) for the ICP / Tempstar / Heil YC048F heat pump. The defrost board is the brain of the outdoor unit in heating mode — it monitors the defrost thermostat and run time, then commands the reversing valve, energizes the auxiliary heat, and stops the outdoor fan to melt frost off the coil. A 24V control circuit drives the relays and timing logic. When this board fails, the heat pump can ice over completely, fail to defrost, short cycle, or lose communication with the thermostat.

Specifications

Compatibility

Direct-fit replacement for the ICP, Tempstar, and Heil YC048F heat pump and other outdoor units that use OEM defrost board 34332100. Verify the board part number and connector layout against your existing board before installing.

Installation Guide

1. Safety First — Disconnect power at the outdoor disconnect and breaker, then verify zero voltage with a multimeter.
2. Access — Remove the condensing unit electrical/service panel.
3. Document — Photograph every plug, terminal, and wire color on the board before disconnecting.
4. Remove — Unplug the harnesses, release the board standoffs or screws, and lift out the old board.
5. Install — Mount the new board and reconnect each harness to the matching terminal per your photo.
6. Test — Restore power, confirm the board powers up, and verify a normal defrost cycle and reversing valve operation.

Signs You Need a Replacement

• Outdoor coil ices over and never goes into defrost.
• Heat pump short cycles or won't switch between heat and cool.
• Reversing valve or auxiliary heat won't energize on a call.
• No response from the outdoor unit even with correct thermostat signals.

Shipping & Returns

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