ICP 40VA Transformer for WJH330000KTP0A1 — 208/230V to 24V Step-Down | Ships Today

Overview

This is the genuine OEM 40VA control transformer (part #1173691) for ICP, Tempstar, and Heil systems, stepping 208/230V line voltage down to the 24V used by the thermostat and control circuit. The transformer powers the reversing valve coil, contactor coil, and control board low-voltage logic. It works alongside the related reversing valve coil (1172619), 24V reversing valve with coil (1173708), and 24V barrier (1176032) on this heat pump platform. When a transformer fails you'll get a completely dead thermostat, no 24V at the control board, a blown low-voltage fuse, or a system that won't respond to any call.

Specifications

Compatibility

Direct OEM replacement for the 24V control transformer in ICP/Tempstar/Heil model WJH330000KTP0A1 and equivalent heat pump units using part 1173691. Confirm primary tap voltage matches your supply.

Installation Guide

1. Safety First — Disconnect power at the breaker and verify zero voltage with a multimeter.
2. Access — Remove the control panel to reach the transformer.
3. Document — Photograph the primary and secondary lead connections before disconnecting.
4. Remove — Disconnect the primary (line) and secondary (24V) leads and unbolt the old transformer.
5. Install — Mount the new transformer, match the correct primary tap, and reconnect leads per your photos.
6. Test — Restore power and confirm 24V across the secondary and a responsive thermostat.

Signs You Need a Replacement

• Thermostat is completely dead with no 24V present
• Repeatedly blown low-voltage control fuse
• No response on a call for heat, cool, or defrost
• Burnt smell or visible scorching at the transformer

Shipping & Returns

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