OEM Carrier 40VA Control Transformer for Model GB1AAV048091AFJA

This is the factory OEM replacement transformer (part number HT01BC116) for the Carrier GB1AAV048091AFJA packaged gas/electric unit. The transformer steps down line voltage (120V) to 24V AC to power the entire low-voltage control circuit — including the thermostat, contactor coil, gas valve, and control board. When the transformer fails, the system goes completely dark: no thermostat response, no blower, no ignition. It is often the first component to check when nothing in the system responds at all.

• Specs: 40VA rating | Primary: 120V | Secondary: 24V AC | OEM part number HT01BC116 | Factory-matched to Carrier GB1AAV048091AFJA control circuit requirements
• OEM vs Generic: This is a genuine OEM Carrier transformer wound to exact VA and voltage tolerances. Generic transformers may undervolt the control board under load, causing intermittent lockouts, nuisance tripping, or premature control board failure — making the OEM choice the lower-cost option long-term.
• 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 (to verify 24V output post-install). Photograph or label all low-voltage wiring before disconnecting terminals. Check for a blown fuse on the secondary side before condemning the transformer.
• Warranty: 1-year OEM factory warranty against defects. In-stock and ships same business day from our warehouse.

Compatibility: Designed and tested for the Carrier GB1AAV048091AFJA packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages against your unit's data plate before ordering. Our parts specialists are available to confirm fitment — order with confidence and get your system back online today.