OEM Carrier Control Transformer 40VA 120V to 24V for Model GB3AAV036095ADJA

This OEM control transformer (part# HT01BC116) is the factory-specified replacement for the Carrier GB3AAV036095ADJA gas furnace. The transformer steps down line voltage (120V) to the 24V AC signal required by the control board, thermostat, gas valve, and all low-voltage safety circuits. When the transformer fails, the entire control circuit goes dark — the thermostat displays nothing, the furnace will not respond to any call for heat or cooling, and no diagnostic fault codes will appear. If you've confirmed 120V at the unit but zero voltage on the secondary side, this transformer is almost certainly the culprit.

• Specs: 40VA output rating | Primary: 120V AC | Secondary: 24V AC | OEM Part Number: HT01BC116 | Direct drop-in replacement, factory-matched dimensions and lead configuration
• OEM vs Generic: The OEM HT01BC116 transformer is wound to exact VA and impedance specifications for the Carrier control board. Undersized or off-tolerance generic transformers can overload under simultaneous accessory draws (humidifiers, zone boards, EAC), causing nuisance tripping or premature failure of downstream components.
• Install difficulty: 2/5 — Power down the unit at the disconnect and breaker before beginning. Tools needed: flat-head and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all low-voltage wiring connections before disconnecting. Verify 0V on primary leads before handling. Total job time: 20–35 minutes for most technicians.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. In-stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier GB3AAV036095ADJA gas furnace. Always verify your existing transformer's VA rating and voltage markings on the data plate or control board label before ordering to ensure a proper match. If you're unsure of fitment, our HVAC parts specialists verify compatibility before you order — no guesswork required.