ICP Fan Coil Control Board for WAHM422A1 — OEM Replacement | Ships Today

Overview

This OEM fan coil control board (part number 1172975) is the central logic board for your ICP WAHM422A1 air handler. It manages blower timing and speed, interprets thermostat calls, sequences the electric heat strips, and monitors safety inputs. When the board fails, symptoms range from a completely dead air handler to a blower that runs constantly, won't respond to the thermostat, or won't engage auxiliary heat. Power surges, lightning, loose connections arcing at the terminals, and failed relays are the usual causes.

Specifications

Compatibility

Direct OEM replacement for the ICP WAHM422A1 fan coil air handler and matching Tempstar, Heil, and Comfortmaker variants that use the same board. Match the part number and connector layout to your existing board before installing.

Installation Guide

1. Safety First — Disconnect power at the breaker and verify zero voltage with a multimeter before touching the board.
2. Access — Remove the air handler control-compartment service panel.
3. Document — Photograph every wire harness, plug, and terminal connection on the board before disconnecting.
4. Remove — Unplug all connectors, release the mounting standoffs or screws, and lift the failed board out.
5. Install — Seat the new board on its standoffs and reconnect each harness exactly per your photo, confirming every plug is fully latched.
6. Test — Restore power and verify the blower responds correctly to fan, cool, and heat calls.

Signs You Need a Replacement

• Air handler is completely dead with confirmed line and 24V power
• Blower runs continuously and ignores the thermostat
• Electric heat strips fail to energize on a heat call
• Visible scorching, burnt relays, or a burnt smell on the board

Shipping & Returns

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