ICP Transformer for RH5320312 — 40VA 208/240V to 24V | Ships Today

Overview

This OEM control transformer (part number 1540372) steps down line voltage to the 24V control voltage that powers the thermostat, contactor coil, relays, and safety circuits in your ICP RH5320312 system. It accepts a 208/240V primary input and delivers a 24V secondary output rated at 40VA. When a transformer fails, the entire low-voltage control circuit goes dead — the thermostat screen goes blank, the contactor will not pull in, and the system will not start even though high-voltage power is present. A buzzing or visibly burned transformer, or a blown low-voltage fuse that keeps tripping, are classic signs of failure.

Specifications

Compatibility

Engineered for the ICP / Tempstar / Heil / Comfortmaker RH5320312 and other units that originally shipped with OEM transformer 1540372. Always confirm your existing transformer is a 208/240V primary, 24V secondary, 40VA unit before ordering.

Installation Guide

1. Safety First — Disconnect power at the breaker and verify zero voltage at the unit with a multimeter.
2. Access — Remove the service panel to expose the control box.
3. Document — Photograph every wire on the old transformer before disconnecting anything.
4. Remove — Label and disconnect the primary (line) and secondary (24V) leads, then unbolt the transformer from its mounting bracket.
5. Install — Mount the new transformer, reconnect the primary and secondary leads exactly as photographed.
6. Test — Restore power and confirm 24V across the secondary terminals and normal system startup.

Signs You Need a Replacement

• Blank thermostat and dead low-voltage controls with line power present
• Repeatedly blown 3A/5A low-voltage fuse
• Audible buzzing or a burnt-electrical smell from the control box
• No 24V reading across the secondary terminals

Shipping & Returns

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