ICP Transformer for WAHL424B1 — 40VA 208/230V to 24V | Ships Today

Overview

This OEM control transformer (part number 1172028) powers the 24V low-voltage control circuit in your ICP/Tempstar/Heil model WAHL424B1 system. It steps a 208/230V primary down to a 24V, 40VA secondary that feeds the thermostat, contactor, relays, and control board. A failed transformer takes the whole control system offline — the thermostat goes blank, the contactor will not close, and the unit will not start. Shorted secondary wiring, an overloaded control circuit, or aged windings are the most common causes.

Specifications

Compatibility

Direct-fit replacement for ICP, Tempstar, Heil, Comfortmaker, and related International Comfort Products equipment using model WAHL424B1. The 40VA 208/230V-to-24V rating is shared across many ICP air handlers and furnaces — verify the VA and voltage of your existing transformer 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 service panel to expose the control compartment.
3. Document — Photograph all primary and secondary wire connections before disconnecting.
4. Remove — Disconnect the primary (line) and secondary (24V) leads, then unbolt the failed transformer from its bracket.
5. Install — Mount the new transformer, match the primary taps to your supply voltage, and reconnect the secondary leads per your photo.
6. Test — Restore power and confirm 24V across the secondary terminals and normal startup.

Signs You Need a Replacement

• Blank thermostat with no 24V control power.
• Contactor or relays will not energize on a call for heat or cool.
• Control fuse blows repeatedly or the transformer smells burnt.
• No voltage measured across the 24V secondary terminals.

Shipping & Returns

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