ICP 40VA Transformer for WPG4364060RKB1 — 208/230V to 24V | Ships Today

Overview

This is a genuine OEM 40VA control transformer (OEM Part No. 1173691, "TRANS 208/230 to 24 40VA") with its 24V barrier (OEM Part No. 1178431) for the ICP / Tempstar / Heil WPG4364060RKB1 gas/electric packaged unit. The control transformer steps the unit's 208/230V line voltage down to the 24V low-voltage power that runs the thermostat, control board, contactor coil, gas valve, and safety circuits. Essentially every control function in the system depends on this transformer producing clean 24V. Rated at 40VA, it supplies enough capacity to drive the full low-voltage load of the packaged unit. Transformers fail from overload, shorted low-voltage wiring, voltage surges, and age-related insulation breakdown. When a transformer fails — often by burning open or tripping its internal fuse link — the entire control system goes dead: no thermostat, no calls, no operation. A frequent cause is a pinched or shorted thermostat wire that overloads the secondary. Typical symptoms include a completely unresponsive thermostat, no 24V at the board, a visibly burnt or smelly transformer, and a repeatedly blown low-voltage fuse.

Specifications

Compatibility

This 40VA transformer and 24V barrier are the factory-specified low-voltage control components for the ICP / Tempstar / Heil WPG4364060RKB1 packaged unit and are shared across many ICP-family units that use a 208/230V primary and 24V secondary. Confirm the primary tap, VA rating, and mounting footprint match your original before installing.

Installation Guide

1. Safety First — Disconnect power at the unit and breaker, then verify zero voltage at the transformer primary leads with a multimeter.
2. Access — Remove the control compartment panel to reach the transformer and barrier.
3. Document — Photograph the primary (line) and secondary (24V) wiring before disconnecting anything.
4. Remove — Disconnect the primary and secondary leads, then unbolt the transformer and barrier from the control mount.
5. Install — Mount the new transformer and 24V barrier, connect the correct primary tap for your supply voltage, and reconnect the 24V secondary per your photo.
6. Test — Restore power and confirm 24V at the secondary and a responsive thermostat before checking heating and cooling calls.

Signs You Need a Replacement

• Thermostat is completely dead and the system won't respond to any call.
• No 24V output at the control board secondary terminals.
• Transformer is burnt, discolored, or has a hot electrical smell.
• Low-voltage fuse blows immediately after replacement (check for a shorted 24V wire first).

Shipping & Returns

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