ICP Control Transformer for WPG4484090LKB1 — 40VA 208/230V to 24V | Ships Today

Overview

This OEM control transformer steps down line voltage (208/230V) to the 24V control circuit that powers your ICP, Tempstar, and Heil equipment's thermostat, contactor coil, gas valve, and ignition control. Rated at 40VA, it supplies the low-voltage power that runs the entire control board logic. When a transformer fails, the system goes completely dead at the thermostat — no fan, no cooling, no heat — and you'll often find a blown low-voltage fuse or burnt transformer windings. This listing includes OEM part number 1173691 (transformer) and 1178431 (24V barrier).

Specifications

Compatibility

Designed for ICP / Tempstar / Heil model WPG4484090LKB1 packaged units and other systems using a 40VA 208/230V-to-24V control transformer. Always verify the primary and secondary voltage and VA rating against your existing part.

Installation Guide

1. Safety First — Disconnect power at the breaker and verify zero voltage with a multimeter.
2. Access — Remove the control panel access cover.
3. Document — Photograph all primary and secondary wire connections before disconnecting.
4. Remove — Disconnect the line-voltage primary leads and the 24V secondary leads, then unscrew the transformer from its mounting bracket.
5. Install — Mount the new transformer, match primary to the correct line-voltage tap (208 or 230), and reconnect the 24V secondary per your photo.
6. Test — Restore power and confirm 24V at the secondary terminals and normal thermostat operation.

Signs You Need a Replacement

• System completely unresponsive at the thermostat (no heat, cool, or fan)
• Repeatedly blown 24V control fuse
• No 24V reading at the secondary terminals with line voltage present
• Burnt smell or visibly scorched transformer windings

Shipping & Returns

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