ICP Transformer for WFAR100C066B1 – 40VA 120/24V | Ships Today

Overview

This OEM control transformer steps the 120V line voltage down to the 24V the control circuit needs in your ICP / Heil / Tempstar WFAR100C066B1 air handler. Rated at 40VA, it powers the thermostat, relays, and control board's low-voltage side. When a transformer fails, the entire 24V control circuit goes dead: the thermostat is blank, no relays pull in, and the system won't respond. A buzzing, hot, or burnt-smelling transformer is also a clear sign of failure. This direct-fit replacement (part 1177217) restores reliable 24V control power.

Specifications

Compatibility

Direct OEM replacement for the ICP, Tempstar, Heil, and Comfortmaker WFAR100C066B1 air handler / fan coil. Confirm the primary voltage tap (120V) and VA rating match your existing transformer before installing.

Installation Guide

1. Safety First – Disconnect power at the breaker and verify zero voltage with a multimeter.
2. Access – Remove the service panel to reach the transformer.
3. Document – Photograph the primary and secondary lead positions before disconnecting.
4. Remove – Disconnect the leads and unbolt the transformer from its bracket.
5. Install – Mount the new transformer and reconnect the 120V primary and 24V secondary leads per your photo.
6. Test – Restore power and confirm 24V at the secondary with a multimeter.

Signs You Need a Replacement

• Blank thermostat / no 24V control power
• Relays won't energize and system won't start
• Transformer buzzes, runs hot, or smells burnt
• Repeatedly blown low-voltage fuse

Shipping & Returns

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