ICP 24V Control Transformer for RGS240HEFA0AAAA — 40VA Class 2 | Ships Today

Overview

This OEM 24-volt control transformer powers the low-voltage control circuit on your ICP / Heil / Tempstar RGS240HEFA0AAAA gas furnace. It steps the incoming 120V line voltage down to the 24V needed by the relays, contactor coils, thermostat, gas valve and control board (OEM relay components 1183814 DPDT and 1178205 DPST operate on this same 24V control bus). Rated at 40VA Class 2, it delivers stable, fused-class low-voltage power throughout the heating cycle. When a control transformer fails, the entire system goes dead — no blower, no ignition, and a thermostat with a blank screen — because nothing on the 24V side has power. A buzzing transformer, a blown low-voltage fuse that keeps recurring, or a burnt-coil smell are classic signs the transformer is failing or shorted.

Specifications

Compatibility

Engineered as a direct-fit replacement for the ICP / Heil / Tempstar / Comfortmaker RGS240HEFA0AAAA gas furnace and shared platform models that use the same 24V control assembly. Always confirm your unit's primary voltage and VA rating against the original before installing.

Installation Guide

1. Safety First — Disconnect power at the furnace switch and breaker, then verify zero voltage with a multimeter.
2. Access — Remove the furnace blower/control compartment service panel.
3. Document — Photograph all primary and secondary wire connections before disconnecting.
4. Remove — Disconnect the 120V primary leads and 24V secondary leads, then unbolt the failed transformer from the bracket.
5. Install — Mount the new transformer, reconnect primary and secondary wiring exactly per your photo.
6. Test — Restore power, confirm 24V at the secondary with a meter, and verify the furnace completes a full call for heat.

Signs You Need a Replacement

• Furnace completely dead — no blower, ignition, or thermostat power
• Low-voltage fuse blows repeatedly after replacement
• Audible buzzing or humming from the transformer
• Burnt smell or visible scorching on the transformer housing

Shipping & Returns

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