Tempstar 24V Transformer for TCH042AKC3 — 40VA Control Circuit | Ships Today

Overview

This OEM 24-volt control transformer (Tempstar part 34329055) provides low-voltage 24V power to the control circuit of your Tempstar TCH042AKC3 heat pump, feeding the reversing valve solenoid, contactor coil, and thermostat circuit. Rated at roughly 40VA, it converts line voltage to the 24VAC that modern HVAC controls require. A failed control transformer kills all low-voltage power: the system won't energize, the thermostat goes dark, and neither heating nor cooling will operate. Buzzing, a repeatedly blown low-voltage fuse, or a scorched secondary winding all indicate a transformer at the end of its life.

Specifications

Compatibility

Engineered as a direct-fit OEM replacement for the Tempstar TCH042AKC3 heat pump. ICP-family units (Tempstar, Heil, Comfortmaker, Carrier, Bryant) often share this control component — verify part number 34329055 before ordering.

Installation Guide

1. Safety First — Disconnect power at the breaker and verify zero voltage with a multimeter before touching wiring.
2. Access — Remove the control-panel service cover to reach the transformer.
3. Document — Photograph all primary and secondary connections before disconnecting.
4. Remove — Disconnect the line-voltage primary and 24V secondary leads, then unbolt the failed transformer.
5. Install — Mount the new transformer and reconnect primary and secondary leads exactly per your photo.
6. Test — Restore power and confirm 24VAC at the secondary terminals and that the system energizes.

Signs You Need a Replacement

• System completely dead with no low-voltage power
• Blank or unresponsive thermostat
• Repeatedly blown low-voltage fuse
• Audible buzzing or burning smell from the transformer

Shipping & Returns

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