ICP Defrost Control Board for YG042G — OEM Heat Pump Part 34332101 | Ships Today

Overview

This genuine OEM defrost control board (part number 34332101) manages the defrost sequence on your ICP / Heil / Tempstar YG042G heat pump. The board tracks outdoor coil temperature and accumulated run time, then initiates a timed defrost — reversing the valve, stopping the outdoor fan, and energizing the supplemental heat — to clear frost from the coil in cold weather. A failed board causes ice buildup that chokes airflow and destroys heating capacity, or causes excessive defrosting that wastes energy and short cycles the equipment. It runs on a 24V control circuit and carries the full defrost timing and sensor logic for the unit.

Specifications

Compatibility

Direct-fit replacement for the ICP, Heil, Comfortmaker, and Tempstar YG042G heat pump. Confirm the existing board part number and terminal arrangement against 34332101 before installing.

Installation Guide

1. Safety First — Disconnect power at the outdoor disconnect and verify zero voltage with a multimeter.
2. Access — Remove the outdoor unit's electrical access panel.
3. Document — Photograph every wire, plug, and sensor lead before disconnecting.
4. Remove — Unplug the low-voltage harness and defrost sensor, remove the mounting screws, and lift out the old board.
5. Install — Mount the new 34332101 board, reconnect each lead per your photo, and reseat the defrost thermostat/sensor.
6. Test — Restore power and verify a normal heating call plus a forced defrost cycle complete correctly.

Signs You Need a Replacement

• Outdoor coil ices over during heating operation
• Unit never initiates or never terminates defrost
• Rapid cycling between heating and defrost modes
• No 24V output to the reversing valve or fan during defrost

Shipping & Returns

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