OEM Carrier Control Transformer 40VA for Model GB1AAV036111ADJA

This OEM control transformer (part number HT01BC116) is the factory-specified replacement for the Carrier GB1AAV036111ADJA packaged or split-system unit. The transformer steps down 120V line voltage to the 24V signal voltage required to power your thermostat, control board, and all low-voltage system controls. When the transformer fails, the entire control circuit goes dead — the thermostat goes blank, the system won't respond to any call for heating or cooling, and no low-voltage components will operate. It is often the first component to check when a unit appears completely unresponsive despite confirmed line voltage at the disconnect.

• Specs: 40VA output rating | Primary: 120V AC | Secondary: 24V AC | Replaces OEM part number HT01BC116 | Factory-matched construction for long service life
• OEM vs Generic: This is a genuine OEM Carrier transformer wound to factory specifications. Generic transformers frequently use thinner gauge wire and lower-grade core laminations, making them prone to overheating and premature burnout — especially in high-demand multi-stage systems.
• Install difficulty: 2/5 — Shut off all power to the unit at the disconnect and breaker before beginning work. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter, wire nuts or spade terminals. Photograph all low-voltage wiring connections before disconnecting the old transformer. Verify correct VA rating before energizing.
• Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship same business day from our climate-controlled warehouse.

Compatibility: Designed and verified for the Carrier GB1AAV036111ADJA. Always confirm the primary voltage, secondary voltage, and VA rating on your unit's data plate before ordering. Our parts team is available to verify fitment — reach out before you order if you have any questions.