ICP 40VA Transformer 208/230V to 24V for WPG4484090RKB1 — OEM 1173691 | Ships Today

Overview

This OEM 40VA control transformer (part 1173691, TRANS 208/230>24 40VA) with its 24V terminal barrier (part 1178431, BARRIER 24V) is the direct-fit replacement for the ICP/Tempstar/Heil WPG4484090RKB1 unit. The transformer steps the 208/230V line down to the 24V low-voltage control circuit that powers the thermostat, control board, gas valve, and relays. When a transformer fails — usually from a control short or age — the entire low-voltage system goes dead: no thermostat display, no call for heat or cool, and no contactor pull-in. A new 40VA transformer restores control power to the whole system.

Specifications

Compatibility

Designed for the ICP/Tempstar/Heil WPG4484090RKB1 and matching-platform units using a 40VA, 208/230-to-24V control transformer. Confirm primary tap voltage and VA rating against your original before installing.

Installation Guide

1. Safety First — Disconnect power at the disconnect and breaker; verify zero voltage with a multimeter.
2. Access — Remove the control-panel cover to expose the transformer.
3. Document — Photograph the primary and secondary wiring, including the tap used.
4. Remove — Label and disconnect the leads, then unbolt the failed transformer.
5. Install — Mount the new transformer and barrier, wire the correct primary tap, and reconnect 24V leads per your photo.
6. Test — Restore power and confirm 24V across the secondary and normal thermostat operation.

Signs You Need a Replacement

• Blank thermostat or no 24V control power
• System won't respond to heat or cool calls
• Burnt-smelling or visibly scorched transformer
• Repeated blown low-voltage fuse

Shipping & Returns

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