Tempstar 40VA 277V-to-24V Transformer for TEB15R25RTA — OEM | Ships Today

Overview

This is a genuine OEM 40VA step-down control transformer for the Tempstar TEB15R25RTA packaged terminal air conditioner, part number 1091226, which steps 277-volt line power down to the 24-volt control voltage the unit needs. The TEB15R25RTA control package also uses two 24V relays — a standard relay (1053004) and a DPST relay (1060940) — that switch on the transformer's low-voltage output. A failed transformer leaves the entire control circuit dead: no thermostat response, no relay action, and no operation at all.

Specifications

Compatibility

Designed as a direct-fit replacement for the Tempstar TEB15R25RTA PTAC. The same 40VA 277-to-24V transformer and companion relays are shared across related ICP, Heil, and Comfortmaker TEB15-series 277V PTAC units. Confirm part number 1091226 and your supply voltage before ordering.

Installation Guide

1. Safety First — Disconnect 277V power at the breaker and verify zero voltage with a multimeter; 277V is lethal.
2. Access — Remove the front cabinet and control-box service panel.
3. Document — Photograph the primary and secondary leads before disconnecting.
4. Remove — Disconnect the line and load wires and unbolt the transformer from its bracket.
5. Install — Mount the new transformer, wire 277V to the primary and 24V to the secondary per your photo.
6. Test — Restore power and confirm 24 VAC at the secondary and that the relays energize.

Signs You Need a Replacement

• Unit completely dead with no control response.
• No 24 VAC measured at the transformer secondary.
• Repeated blown low-voltage fuses or tripped breakers.
• Burnt smell, scorching, or a swollen transformer body.

Shipping & Returns

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