OEM Carrier 40VA Control Transformer HT01BC116 for Model GB3AAV024050ACJA

This is the factory OEM replacement control transformer (part number HT01BC116) for the Carrier GB3AAV024050ACJA gas air handler. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, control board, and all low-voltage switching in the system. When this component fails, absolutely nothing responds — the thermostat goes blank, the system won't call for heat or cooling, and no error codes appear because the control circuit has lost power entirely. If you've already ruled out a blown fuse or tripped breaker and your 24V circuit is dead, this transformer is the most common culprit.

• Specs: 40VA rating | 120V primary / 24V secondary | Class 2 output | Direct OEM replacement for part number HT01BC116 | Factory-matched impedance and thermal protection
• OEM vs Generic: OEM transformers are wound to exact VA capacity and include internal thermal cutouts that protect your control board from surge damage. Generic units frequently underperform at rated load, causing intermittent low-voltage issues that are notoriously difficult to diagnose.
• Install difficulty: 2/5 — Shut off power at the breaker and verify with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Photograph all wiring connections before disconnecting. Primary (120V) wires connect to line voltage; secondary (24V) wires connect to the control board low-voltage terminals.
• Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship the same business day from our warehouse.

Compatibility: Engineered specifically for the Carrier GB3AAV024050ACJA gas air handler. Always verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate or old transformer label before ordering to confirm fitment. Our HVAC parts specialists are available to verify compatibility before you buy — no guesswork required.