ICP 40VA Transformer for WFAR040A030B1 — 120V to 24V | Ships Today

Overview

This is a genuine OEM 40VA control transformer (part number 1177217) for the ICP/Tempstar/Heil WFAR040A030B1 furnace. The transformer steps the 120V line voltage down to the 24V control voltage that powers your thermostat, control board, gas valve, and relays. When a transformer fails, the entire low-voltage control circuit goes dead — the thermostat screen goes blank, the furnace will not respond to a call for heat, and nothing energizes even though line power is present. Transformers commonly fail from a shorted thermostat wire, a stuck contactor, or simple age and heat fatigue. This 40VA unit provides the rated capacity to drive the furnace's full control load.

Specifications

Compatibility

Direct factory replacement for the ICP/Tempstar/Heil WFAR040A030B1 furnace and the Comfortmaker, Arcoaire, and KeepRite versions of this model platform. Confirm the 120V primary tap and 24V secondary match your existing wiring before installation.

Installation Guide

1. Safety First — Disconnect power at the furnace switch and breaker, then verify zero voltage with a multimeter.
2. Access — Remove the control compartment service panel.
3. Document — Photograph the primary and secondary leads before disconnecting.
4. Remove — Unbolt the old transformer and disconnect its leads.
5. Install — Mount the new transformer, wire the 120V primary and 24V secondary per your photo, and verify all connections are tight.
6. Test — Restore power and confirm 24V across the secondary with a multimeter.

Signs You Need a Replacement

• Blank thermostat and dead control circuit
• Furnace will not respond to a call for heat
• No 24V reading across the secondary terminals
• Burnt smell or visible scorching on the transformer

Shipping & Returns

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