ICP Defrost Control Board for YK018G — Heat Pump 24V | Ships Today
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Overview
This OEM defrost control board (part number 34332101) is the brain of the defrost cycle on your ICP/Heil/Tempstar YK018G heat pump. It monitors coil temperature and run time, then commands the reversing valve and shuts off the outdoor fan to melt frost from the outdoor coil during heating season. When this board fails you may see the outdoor unit ice over and stay frozen, no heat in heat-pump mode, the unit stuck in defrost, or the compressor and fan failing to cycle correctly. Because it coordinates the compressor contactor, reversing valve, and fan on a 24-volt control circuit, a faulty defrost board can mimic many other failures — replacing it restores proper, efficient defrost timing.
Specifications
| Spec | Value |
|---|---|
| Part Number | 34332101 |
| Type | Defrost Control Board |
| Brand | ICP (Heil / Tempstar / Comfortmaker) |
| Control Voltage | 24 VAC |
| Function | Defrost timing, reversing valve & fan control |
| Fitment | OEM Direct Replacement |
Compatibility
A direct OEM replacement for the ICP/Heil/Tempstar YK018G heat pump and related outdoor units originally equipped with part 34332101. Verify the board's connector layout and part number against your existing board before installing.
Installation Guide
- Safety First — Disconnect power at the disconnect and breaker, then verify zero voltage with a multimeter.
- Access — Remove the condenser control-panel cover to reach the board.
- Document — Photograph every wire harness and terminal position before disconnecting.
- Remove — Unplug the harness connectors, release the board standoffs/screws, and lift out the old board.
- Install — Seat the new board on its standoffs and reconnect each harness per your photo and the wiring diagram.
- Test — Restore power and confirm normal operation; initiate a test defrost if your model supports the speed-up pins.
Signs You Need a Replacement
- Outdoor coil ices up and never defrosts
- No heat or weak heat in heat-pump mode
- Unit stuck in defrost or short-cycling
- Reversing valve or outdoor fan not switching on schedule
Shipping & Returns
Ships same day on orders placed before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.
Shipping Information
- Orders placed before 3PM CST ship same business day
- Standard delivery: 2-5 business days
- Express shipping available at checkout
- Free shipping on orders over $75
- Tracking number emailed upon shipment
Return Policy
- 30-day returns on unused parts in original packaging
- Electrical parts (capacitors, contactors, control boards) are final sale once installed
- Email info@nationalhvacparts.com to initiate a return
- Refunds processed within 5-7 business days