OEM Carrier 40VA Control Transformer for Model GB3AAV024050AEJA

This OEM control circuit transformer (part number HT01BC116) is the factory-specified replacement for the Carrier GB3AAV024050AEJA gas furnace. The transformer steps down 120V line voltage to the 24V signal used by your thermostat, control board, gas valve, and all low-voltage safety circuits. When it fails, nothing works — the thermostat goes blank, the system will not respond to any call for heat or cool, and fault codes may not even display because the control board itself has lost power.

• Specs: 40VA rated | Primary: 120V | Secondary: 24V | Hardwired lead connections | Factory-matched impedance for Carrier low-voltage circuits
• OEM vs Generic: OEM transformers from Carrier are wound to exact VA and impedance specifications, preventing nuisance tripping of the internal thermal fuse under normal load. Generic units rated at nominal 40VA often run at lower actual capacity, causing premature failure when the control board and gas valve draw simultaneously.
• Install difficulty: 2/5 — Disconnect power at the breaker and confirm zero voltage with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or push-in connectors. Photograph all wiring connections before removal. Check secondary side for a short in the low-voltage circuit before installing the new transformer.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. Ships same business day from our stocked warehouse.

Compatibility: Engineered for the Carrier GB3AAV024050AEJA gas furnace. Always verify your existing transformer's primary and secondary voltage ratings as well as the VA rating on the data label before ordering. If your system has added accessories (humidifiers, UV lights, zoning boards), confirm total VA draw does not exceed 40VA. Our fitment team is available to verify compatibility before you order — same-day shipping on all in-stock parts.