ICP 40VA Transformer for WFHR080B048A1 — 120/24V | Ships Today

Overview

This is the OEM control transformer (part #1177217) for the ICP/Tempstar/Heil WFHR080B048A1 gas furnace. The transformer steps the incoming 120-volt line power down to the 24-volt control voltage that powers the thermostat, control board, gas valve, and relays. Rated at 40VA, it supplies enough capacity to drive the furnace's low-voltage circuit plus a typical thermostat and accessories. When the transformer fails — usually from a shorted secondary or an overloaded control circuit — the entire 24V system goes dead and the furnace becomes completely unresponsive.

Specifications

Compatibility

Direct OEM replacement for the ICP WFHR080B048A1 furnace and equivalent Tempstar, Heil, and Comfortmaker units using a 40VA 120-to-24V transformer. Verify your primary tap is 120V (not 208/240V) before installing.

Installation Guide

1. Safety First — Disconnect power at the furnace switch and breaker, then verify zero voltage with a multimeter.
2. Access — Remove the furnace control compartment service panel.
3. Document — Photograph the primary and secondary wire connections before disconnecting.
4. Remove — Disconnect the leads, remove the mounting screw or bracket, and take out the failed transformer.
5. Install — Mount the new transformer, connect the 120V primary and 24V secondary leads per your photo, and verify there are no shorts.
6. Test — Restore power and confirm 24V across the secondary, then run a heat cycle.

Signs You Need a Replacement

• No 24V at the control board or thermostat
• Thermostat screen blank with C-wire power
• Burnt smell or visibly charred transformer windings
• Repeated blown low-voltage fuses on the control board

Shipping & Returns

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