OEM Carrier Furnace Transformer 120V–24V 40VA for Model PG8UAA048091ABJA

This OEM step-down transformer is the factory-specified replacement for the Carrier PG8UAA048091ABJA gas furnace. It converts 120V line voltage to the 24V AC signal that powers every low-voltage component in your system — thermostat, gas valve, inducer relay, control board, and more. When the transformer fails, the entire control circuit goes dark: the thermostat display may go blank, the furnace will not respond to a call for heat, and nothing will turn on. Replaces discontinued OEM part number HT01BC116; current superseding OEM part number is HT680054.

• Specs: Primary Input: 120V AC | Secondary Output: 24V AC | VA Rating: 40VA | Frequency: 60Hz | Mounting: Foot mount | Connection: Wire leads with insulated female connectors
• OEM vs Generic: OEM transformers are wound to exact factory VA tolerances, protecting sensitive downstream components like the control board and gas valve from voltage sag. Generic units often under-deliver true VA output, causing erratic lockouts and premature board failure.
• Install difficulty: 2/5 — Always shut off power at the breaker before starting. Tools needed: flathead and Phillips screwdriver, needle-nose pliers, multimeter. Label or photograph all wiring connections before removal. Check voltage between the C and R terminals on the control board after installation to confirm 24V output.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before 3PM local time.

Compatibility: Fits Carrier model PG8UAA048091ABJA gas furnace. This part also cross-references HT01BC116, HT680054, HT01BC115, HT01BB126, HT01BC120, and several additional legacy Carrier/Bryant/Payne part numbers — verify your unit's data plate voltage and VA rating before ordering. Have questions about fitment? Our HVAC parts specialists confirm compatibility before you buy.