ICP Transformer for WAXM304A1 — 208/230V to 24V 40VA Control Transformer | Ships Today

Overview

This is a genuine OEM 40VA control transformer (part number 1172028) for the ICP WAXM304A1 air handler. It steps the 208/230V line voltage down to the 24V low-voltage power that runs the thermostat, control board, relays, and contactor coil. The 40VA rating defines how much low-voltage load the transformer can carry continuously. When a control transformer fails — often from a shorted thermostat wire, a stuck contactor, or simple age — the entire 24V control circuit goes dead, so the system will not respond to the thermostat even though line power is present. A burnt smell, a tripped internal fuse link, or zero volts on the secondary are common clues. Installing the correct OEM transformer restores reliable 24V control power.

Specifications

Compatibility

Factory control transformer for the ICP WAXM304A1 air handler and matching Heil, Tempstar, and Comfortmaker units built on the WAXM304 platform. Confirm the 208/230V primary and 40VA rating on your existing transformer before ordering.

Installation Guide

1. Safety First — Disconnect power at the breaker and unit disconnect, then verify zero voltage with a multimeter.
2. Access — Remove the air handler control compartment service panel.
3. Document — Photograph all primary and secondary wire connections before disconnecting.
4. Remove — Label and disconnect the primary and secondary leads, then unbolt the failed transformer from the panel.
5. Install — Mount the new transformer, match the 208/230V primary taps, and reconnect the 24V secondary per your photos.
6. Test — Restore power and confirm 24V across the secondary and normal thermostat response.

Signs You Need a Replacement

• System completely unresponsive to the thermostat with line power present
• No 24V reading across the secondary terminals
• Burnt smell or visibly scorched transformer housing
• Contactor or relays will not pull in on a call

Shipping & Returns

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