Tempstar 40VA Transformer for TCA736GKA100 — 208/230V to 24V | Ships Today

Overview

This genuine OEM control transformer (part number 1170676) supplies low-voltage power for the Tempstar TCA736GKA100 system. It steps 208/230 volt line power down to 24 volts and is rated at 40VA, providing the control voltage that runs the contactor coil, thermostat circuit, and other 24V components. The transformer is the heart of the control circuit — if it fails, the system loses all low-voltage operation. A burned-out or shorted transformer commonly results from a shorted thermostat wire, a stuck contactor drawing excess current, or a 24V short to ground, so it is good practice to find and correct the underlying fault before installing the replacement.

Specifications

Compatibility

This 40VA transformer is the factory replacement for the Tempstar TCA736GKA100 and is shared across many ICP-family units, including matching Heil, Comfortmaker, and Day & Night equipment that uses a 208/230V-to-24V 40VA control transformer. Verify the primary/secondary voltages and the VA rating against your existing transformer before installing.

Installation Guide

1. Safety First — Disconnect power at the disconnect and breaker, then verify zero voltage with a multimeter.
2. Access — Remove the electrical access panel to reach the transformer.
3. Document — Photograph the primary and secondary wiring before disconnecting.
4. Remove — Label and disconnect the line-voltage primary leads and the 24V secondary leads, then unbolt the transformer from its mount.
5. Install — Mount the new transformer, connect the correct primary tap for your supply voltage (208 or 230V), and reconnect the 24V secondary as photographed.
6. Test — Restore power and confirm 24V across the secondary terminals and proper control operation.

Signs You Need a Replacement

• No 24V control voltage — thermostat and contactor are dead.
• System completely unresponsive on a call for cooling.
• Visible burning, melted casing, or a burnt smell at the transformer.
• Zero output on the secondary while line voltage is present at the primary.

Shipping & Returns

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