Tempstar Defrost Control Board for TCH242AKA1 — Heat Pump | Ships Today

Overview

This is the genuine OEM defrost control board (part #1086070) for the Tempstar TCH242AKA1 heat pump. The defrost board is the brain of the outdoor unit's defrost cycle — it monitors the defrost thermostat and run time, then commands the reversing valve and shuts off the outdoor fan to melt frost off the coil during cold-weather operation. It also manages compressor timing and contactor energization. When the board fails, the heat pump may ice over solid, skip defrost entirely, run defrost too often, or fail to start the compressor. Because it coordinates several components, an intermittent or failed defrost board can produce confusing, hard-to-diagnose symptoms.

Specifications

Compatibility

Direct OEM replacement for the Tempstar TCH242AKA1 heat pump and compatible ICP/Heil/Comfortmaker outdoor units that use this defrost board. Match the part number and connector layout to your existing board before installing.

Installation Guide

1. Safety First — Disconnect power at the outdoor disconnect and verify zero voltage with a multimeter.
2. Access — Remove the control-panel cover to expose the board.
3. Document — Photograph every wire and connector position; defrost boards have many terminals.
4. Remove — Unplug harnesses, release the board standoffs/screws, and lift the old board out.
5. Install — Seat the new board on the standoffs and reconnect every harness exactly per your photo.
6. Test — Restore power, run a heating call, and verify normal operation; force or wait for a defrost cycle to confirm correct sequencing.

Signs You Need a Replacement

• Outdoor coil ices over and never goes into defrost
• Unit runs defrost constantly or at the wrong times
• Compressor or outdoor fan won't energize on a call
• No 24V output to the contactor or reversing valve when expected

Shipping & Returns

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