Tempstar 40VA Transformer for T9UHX060F12A1 — 115V to 24V Control | Ships Today

Overview

This genuine OEM 40VA control transformer (ICP/Tempstar part #1172810) powers the low-voltage control circuit on the Tempstar T9UHX060F12A1 gas furnace. It steps the 115V line voltage down to the 24V needed by the thermostat, control board, gas valve, and ignition system. The 40VA rating provides ample current for the furnace's control loads. When a transformer fails — typically from a control-circuit short, a shorted gas valve, or age — the entire 24V system goes dead: the thermostat blanks out, the blower and ignition won't energize, and the furnace will not respond to a call for heat. Installing this exact-replacement transformer restores full control power.

Specifications

Compatibility

Built for the Tempstar T9UHX060F12A1 gas furnace and shared across ICP-family units (Tempstar, Heil, Comfortmaker, Arcoaire) using a 40VA 115/24V control transformer. Verify your existing transformer's primary and secondary voltages before ordering.

Installation Guide

1. Safety First — Disconnect power at the furnace switch and breaker; verify zero voltage with a multimeter.
2. Access — Remove the control/blower compartment service panel.
3. Document — Photograph every primary and secondary wire connection before disconnecting.
4. Remove — Label and disconnect the leads, then unbolt the failed transformer from its mounting bracket.
5. Install — Mount the new transformer and reconnect the 115V primary and 24V secondary leads exactly per your photo.
6. Test — Restore power, confirm 24V at the secondary with a multimeter, and verify the thermostat and ignition sequence operate.

Signs You Need a Replacement

• Thermostat display is blank with no 24V power
• Furnace does not respond to a heat call
• No measurable 24V at the transformer secondary
• Transformer is hot, buzzing, or shows scorch marks

Shipping & Returns

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