ICP Transformer for WFMR045A024B3 — 40VA 120/24V Class 2 | Ships Today

Overview

This OEM control transformer (part number 1177217) provides the 24V low-voltage power that runs your ICP furnace's control circuit — thermostat, gas valve, igniter sequence, and control board. It steps the 120V primary down to a 24V Class 2 secondary rated at 40VA. A failed transformer kills the entire control circuit: the thermostat goes blank, nothing energizes on a call for heat, and the system looks dead even with line power present. Repeated blown low-voltage fuses, audible buzzing, or visibly scorched windings indicate the transformer has failed and should be replaced.

Specifications

Compatibility

Direct-fit OEM replacement for ICP / Tempstar / Heil model WFMR045A024B3 and related ICP-family gas furnaces using the 120/24V 40VA control platform. Verify the printed primary/secondary voltages and VA rating against your original transformer before installing.

Installation Guide

1. Safety First — Disconnect power at the switch and breaker, then verify zero voltage at the transformer leads with a multimeter.
2. Access — Remove the furnace control/blower access panel.
3. Document — Photograph every primary and secondary lead and its terminal before disconnecting.
4. Remove — Disconnect the 120V primary leads and the 24V secondary leads, then unbolt the transformer from its bracket.
5. Install — Mount the new transformer, reconnect primary and secondary leads exactly per your photo, and confirm the ground.
6. Test — Restore power and confirm 24V at the secondary and a normal heating call.

Signs You Need a Replacement

• Thermostat is blank and the system is completely unresponsive
• Low-voltage control fuse blows repeatedly
• Audible buzzing or humming from the transformer
• No 24V reading at the secondary terminals

Shipping & Returns

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