ICP 40VA Transformer for WAHT604A2 — 208/230V to 24V | Ships Today

Overview

This genuine OEM control transformer (part number 1172028) for the ICP / Tempstar / Heil WAHT604A2 air handler steps 208/230 volts of line power down to a 24-volt, 40VA control output. That low-voltage power feeds the thermostat, fan coil control board, relays, and safety circuits. A 40VA rating provides enough capacity for the control board, blower relay, and a typical thermostat load. When this transformer fails — from an internal short, overload, or age — the unit loses all low-voltage control: the thermostat goes dark and the blower will not energize on a heating or cooling call. Typical symptoms include a dead thermostat, a buzzing transformer, repeatedly blown fuses, and a burnt odor in the control compartment.

Specifications

Compatibility

A direct OEM replacement for the ICP / Tempstar / Heil WAHT604A2 air handler and related ICP units using the 208/230V-to-24V 40VA control platform. Verify the 1172028 part number on your existing transformer for an exact match before ordering.

Installation Guide

1. Safety First — Disconnect power at the breaker and verify zero voltage with a multimeter.
2. Access — Remove the air handler service panel to reach the control box.
3. Document — Photograph all primary and secondary wiring before disconnecting.
4. Remove — Confirm the 208/230V primary tap is wired correctly, label the leads, disconnect, and unbolt the old transformer.
5. Install — Mount the new 40VA transformer, matching the primary lead to your incoming line voltage, and reconnect per your photo.
6. Test — Restore power and verify 24V across the secondary and normal blower/thermostat operation.

Signs You Need a Replacement

• Thermostat is blank or unresponsive
• Low-voltage fuse blows repeatedly
• Loud humming or buzzing from the transformer
• Burnt smell or scorch marks on the transformer housing

Shipping & Returns

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