OEM Carrier 40VA Control Transformer HT01BC116 for Model GA1AAD060100ABJA

This OEM Carrier control transformer (part number HT01BC116) is the factory-specified replacement for the GA1AAD060100ABJA packaged gas/electric unit. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, control board, and every relay in the system. When this component fails, the entire control circuit goes dark — your thermostat displays nothing, the system won't respond to calls for heating or cooling, and no components will energize. A blown fuse on the secondary side is often the first clue; a failed transformer is frequently the root cause.

• Specs: Input 120V AC | Output 24V AC | 40VA rated | OEM part number HT01BC116 | Factory-matched impedance and thermal protection
• OEM vs Generic: OEM transformers are wound to exact VA and impedance specs for the GA1AAD060100ABJA control board. Generic units are often undersized in practice, causing voltage sag under load that leads to nuisance lockouts and premature control board failure.
• Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter, wire nuts. Photograph all wiring connections before disconnecting the old unit. Verify 24V output with a multimeter before closing the panel.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before 3 PM EST.

Compatibility: Designed and factory-matched for Carrier model GA1AAD060100ABJA. Always verify your existing transformer's input/output voltage and VA rating against your unit's data plate before ordering. If you're unsure of fitment, our HVAC parts specialists are available to confirm compatibility before you purchase — no guesswork required.