ICP Transformer for WAHL604B2 — 40VA 208/230V to 24V | Ships Today

Overview

This is a genuine OEM control transformer (part number 1172028) for the ICP/Tempstar/Heil WAHL604B2 air handler. It steps the 208/230V line voltage down to the 24V (40VA) control voltage that powers the thermostat, contactor coil, relays, and control board. When this transformer fails, the entire low-voltage control circuit goes dead even with line power present — a blank thermostat, a system that will not energize, or a unit that hums but never starts are the telltale signs. The 40VA rating supplies enough capacity for a typical residential air handler control load.

Specifications

Compatibility

Engineered as a direct-fit replacement for the ICP/Tempstar/Heil WAHL604B2 air handler. The same 40VA 208/230-to-24V transformer is shared across many ICP-family models — confirm your factory part number is 1172028 before ordering.

Installation Guide

1. Safety First — Disconnect power at the breaker and verify zero voltage with a multimeter before touching any wiring.
2. Access — Remove the air handler service panel to expose the control box.
3. Document — Photograph all primary and secondary wire connections before disconnecting anything.
4. Remove — Label and disconnect the primary (line) and secondary (24V) leads, then unbolt the failed transformer from its bracket.
5. Install — Mount the new transformer, reconnect the line leads to the correct primary tap (208 or 230V) and the 24V leads per your photo.
6. Test — Restore power and confirm 24V across the secondary terminals and normal system operation.

Signs You Need a Replacement

• Blank or dead thermostat with line power present
• System will not energize — no contactor pull-in or blower start
• No measurable 24V across the secondary terminals
• Burnt smell or visibly scorched transformer windings

Shipping & Returns

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