OEM Carrier 40VA Control Transformer HT01BC116 for Model GB1AAV048111ACJA

This is the factory OEM replacement control transformer (part number HT01BC116) for the Carrier GB1AAV048111ACJA packaged gas/electric unit. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, control board, gas valve, and every other low-voltage component in the system. When this part fails, the entire control circuit goes dark — the thermostat becomes unresponsive, the system won't call for heat or cooling, and no fault codes will appear because the board itself has no power.

• Specs: 40VA rated | 120V primary / 24V secondary | Class 2 transformer | Designed for direct OEM drop-in replacement on Carrier GB1AAV048111ACJA packaged units
• OEM vs Generic: This is a genuine Carrier OEM part (HT01BC116), built to exact factory VA ratings and insulation class. Generic transformers often carry loose VA tolerances that can overload and burn out prematurely, especially when multiple 24V accessories such as zone controllers or humidistats are present on the circuit.
• Install Difficulty: 2/5 — Disconnect power at the disconnect box and verify zero voltage before touching any wiring. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to confirm 24V output after install). Label all low-voltage wires before disconnecting. The transformer typically mounts in the control compartment with two screws and uses spade or screw-terminal connections.
• Warranty: 1-year OEM factory warranty against defects. Orders placed before cutoff ship the same business day from our warehouse — get your system back online fast.

Compatibility: Engineered specifically for the Carrier GB1AAV048111ACJA packaged unit. Verify your existing transformer's VA rating and primary/secondary voltage on the data plate before ordering. If you are uncertain about fitment, our HVAC parts specialists are available to confirm compatibility before you buy. In stock and ships today — order now to avoid extended downtime.