ICP 40VA Transformer for WFAR040A030B2 — 120/24V | Ships Today

Overview

This is the OEM 40VA control transformer (part number 1177217) for the ICP/Tempstar/Heil WFAR040A030B2 furnace. The transformer steps the 120V line-voltage primary down to the 24V secondary that powers the thermostat, control board, gas valve, and relays. A failed transformer leaves the entire low-voltage control circuit dead — no thermostat display, no call for heat or cool, and nothing energizes. Transformers commonly fail from a shorted secondary, a thermostat wire grounding out, or age-related winding breakdown. This 40VA unit supplies ample capacity for the furnace control loads and is a direct, plug-in OEM replacement.

Specifications

Compatibility

Direct OEM replacement for the ICP, Tempstar, Heil, and Comfortmaker WFAR040A030B2 model and other units originally fitted with transformer 1177217. Verify 120V primary, 24V secondary, and 40VA rating against 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 furnace control compartment service panel.
3. Document — Photograph the primary and secondary wiring before disconnecting.
4. Remove — Unbolt the old transformer from its bracket and disconnect the leads.
5. Install — Mount the new transformer, land the 120V primary and 24V secondary leads per your photo.
6. Test — Restore power and confirm 24V across the secondary and a normal thermostat call.

Signs You Need a Replacement

• Dead thermostat with no display or power
• No 24V reading across the secondary terminals
• System completely unresponsive to a call for heat or cool
• Burnt smell or visible scorching on the transformer body

Shipping & Returns

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