OEM Carrier 40VA Control Transformer HT01BC116 for Model GB3AAV048090AAJA

This is the factory OEM replacement control transformer (part number HT01BC116) for the Carrier GB3AAV048090AAJA gas furnace. The transformer steps down 120V line voltage to the 24V signal voltage that powers your thermostat, control board, gas valve, and every other low-voltage control component. When it fails, absolutely nothing in the control circuit will respond — the thermostat goes blank, the system won't call for heat, and the furnace sits completely dead despite having full line power. A failed or overloaded transformer is one of the most commonly misdiagnosed furnace problems.

• Specs: 40VA rating | 120V primary / 24V secondary | OEM part number HT01BC116 | Factory-matched to GB3AAV048090AAJA control circuit load requirements
• OEM vs Generic: This OEM transformer is wound to the exact VA capacity and insulation class required by Carrier. Generic transformers often use undersized windings that overheat under normal control circuit load, leading to repeat failures and potential control board damage.
• Install difficulty: 2/5 — Disconnect power at the breaker and verify zero voltage before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter, needle-nose pliers. Label or photograph all wire connections before removing the old transformer.
• Warranty: 1-year OEM factory warranty against defects. Orders placed before cutoff ship same business day from our climate-controlled warehouse.

Compatibility: Designed as a direct OEM replacement for Carrier model GB3AAV048090AAJA. Always verify the primary voltage (120V), secondary voltage (24V), and VA rating on your existing transformer's label before ordering to confirm fitment. Our parts specialists are available to verify compatibility before you purchase — no guesswork required. Order now and get back up and running today.