Tempstar 40VA Transformer for TNK050F12B1 — 115V to 24V (OEM 1011626) | Ships Today

Overview

This OEM control transformer (Tempstar part number 1011626, "TRANS 115>24 40VA") provides the 24-volt control power for the Tempstar TNK050F12B1 furnace. It steps 115V line voltage down to 24V at 40VA to power the control board, gas valve, thermostat circuit, and inducer relay. When the transformer fails — commonly from a shorted control wire, a failed gas valve coil, or age — the furnace goes completely dead: no thermostat display, no board lights, and no response to a heat call. Because a blown transformer is often the symptom of a downstream short, inspect the 24V wiring before energizing the replacement.

Specifications

Compatibility

Direct OEM fit for the Tempstar TNK050F12B1 furnace and other ICP-family units (Heil, Comfortmaker, Tempstar) calling for transformer part 1011626. Confirm the primary/secondary voltages and 40VA rating against your unit before installing.

Installation Guide

1. Safety First — Disconnect power at the switch and breaker. Verify zero voltage with a multimeter.
2. Access — Remove the furnace control-compartment service panel.
3. Document — Photograph the primary (line) and secondary (24V) connections before disconnecting.
4. Remove — Disconnect the wiring, remove the mounting screws, and take out the old transformer.
5. Install — Mount the new transformer and reconnect line and low-voltage leads exactly per your photo.
6. Test — Restore power, confirm 24V across the secondary, and verify normal furnace startup.

Signs You Need a Replacement

• Furnace is completely unresponsive — no 24V control power, blank thermostat.
• No secondary voltage with line power present.
• Burnt smell, discolored case, or melted windings.
• Repeated low-voltage fuse failures traced to the transformer.

Shipping & Returns

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