Tempstar 40VA Transformer for TDE075B12B1 — 115V to 24V Control Transformer | Ships Today

Overview

This is the genuine OEM control transformer (part number 1011626) for the Tempstar TDE075B12B1 gas furnace. It steps the 115 VAC line voltage down to the 24 VAC needed by the furnace control board, thermostat, gas valve, and relays. Rated at 40VA, it supplies enough power for the full low-voltage control circuit including most single-stage cooling and accessory loads. When a transformer fails — usually from a shorted thermostat wire, a stuck contactor coil, or simple age — the entire 24V control system goes dead: no thermostat display, no ignition sequence, and no blower or cooling operation. Replacing the transformer restores low-voltage power to the whole system.

Specifications

Compatibility

Fits the Tempstar TDE075B12B1 furnace and other ICP-family units (Tempstar, Heil, Comfortmaker, Arcoaire) that use the 1011626 115V-to-24V 40VA control transformer. Confirm primary voltage and mounting/terminal style against your existing transformer before installing.

Installation Guide

1. Safety First — Disconnect power at the furnace switch and breaker, then verify zero voltage with a multimeter on both primary and secondary leads.
2. Access — Remove the furnace control-compartment service panel.
3. Document — Photograph and label all primary and secondary wire connections before disconnecting.
4. Remove — Disconnect the leads, unbolt the old transformer from its mounting bracket, and lift it out.
5. Install — Mount the new transformer, reconnect the 115V primary and 24V secondary leads exactly per your photo, and secure all terminals.
6. Test — Restore power and confirm 24 VAC at the secondary and normal thermostat/control operation.

Signs You Need a Replacement

• Thermostat screen is blank and the system is completely unresponsive.
• No 24 VAC measured at the secondary terminals.
• Burnt smell, discoloration, or melted housing on the transformer.
• Repeated blown low-voltage fuses or no control-board activity.

Shipping & Returns

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