OEM Carrier 40VA Control Transformer HT01BC116 for Model GB1AAV048135AFJA

This OEM control transformer (part# HT01BC116) is the factory-specified replacement for the Carrier GB1AAV048135AFJA gas furnace. The transformer steps down 120V line voltage to the 24V low-voltage signal that powers your thermostat, control board, gas valve, and all safety circuits. When this component fails, the entire control circuit goes dark — the thermostat goes blank, the system refuses to respond to any call for heat or cooling, and no other diagnostic troubleshooting will resolve the issue until the transformer is replaced.

• Specs: 40VA rated | 120V primary / 24V secondary | Single-phase | Designed for continuous duty in furnace applications | OEM part number HT01BC116
• OEM vs Generic: This is a factory OEM transformer built to Carrier's exact VA rating and insulation class. Generic transformers often carry inadequate VA ratings, causing them to overheat under full control-circuit load and trip thermal protection repeatedly — shortening the life of every connected component.
• Install difficulty: 2/5 — Shut off power at the disconnect and breaker before starting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter for verification. Label all 24V wiring before disconnecting old unit. Verify 24V output with meter before buttoning up the furnace cabinet.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Engineered specifically for the Carrier GB1AAV048135AFJA gas furnace. Always confirm transformer VA rating and primary/secondary voltage on your unit's wiring diagram or data plate before ordering. Our fitment team is available to verify compatibility before you purchase — ensuring you get the right part the first time and avoid costly return shipping delays.