Tempstar Transformer for TNK075F14B1 — 40VA 115V to 24V | Ships Today

Overview

This OEM control transformer (part number 1011626) steps down 115V line voltage to the 24V control voltage that powers your Tempstar furnace's thermostat, gas valve, ignition control, and relays. Rated at 40VA, it delivers the low-voltage power the control board needs to run the full sequence of operation. A failed transformer produces unmistakable symptoms: a dead thermostat, no response on a call for heat, repeatedly blown low-voltage fuses, or a burnt-electrical smell at the control box. No working transformer means no 24V at the board and no system operation.

Specifications

Compatibility

Direct OEM fit for the Tempstar TNK075F14B1 gas furnace and shared across many ICP-family platforms including Tempstar, Heil, and Comfortmaker furnaces and air handlers that use a 40VA 115-to-24V control transformer. Confirm against your unit's existing transformer rating and mounting before installing.

Installation Guide

1. Safety First — Disconnect power at the furnace switch and breaker, then verify zero voltage with a multimeter at the transformer leads.
2. Access — Remove the furnace service/blower panel to reach the control box.
3. Document — Photograph every wire on the primary (line) and secondary (24V) sides before disconnecting.
4. Remove — Disconnect the primary and secondary leads, then unbolt the transformer from its bracket or control panel.
5. Install — Mount the new transformer and reconnect primary to line voltage and secondary to the 24V common/hot per your photo.
6. Test — Restore power, confirm 24V across the secondary terminals, then run a heat cycle.

Signs You Need a Replacement

• Thermostat screen is dead or the system won't power on.
• Repeatedly blowing the low-voltage (3A) control fuse.
• No 24V reading across the transformer secondary.
• Buzzing, overheating, or a burnt smell from the transformer.

Shipping & Returns

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