OEM Carrier Furnace Control Transformer 40VA 120V–24V for Model PG8UAA048111ACJA

This is the OEM factory-specified control transformer for the Carrier PG8UAA048111ACJA gas furnace. The transformer steps down the 120V line voltage to the 24V AC signal that powers every low-voltage component in the system — thermostat, gas valve, inducer relay, ignition control board, and zone controls. When the transformer fails, the furnace goes completely silent: no call-for-heat response, no inducer startup, nothing. It is one of the first components to check when the entire control circuit is dead.

• Specs: 40VA rating | 120V primary / 24V secondary | 60 Hz single-phase | Foot-mount configuration | Wire lead connection type with pre-installed insulated female quick-connect terminals
• OEM Part Numbers: HT01BC116 (original) / HT680054 (current OEM successor — factory-authorized direct replacement). Also cross-references: HT01BC115, HT01BB126, HT01CT120, HT01BC120, HT01AW115, HT01AA012, HT01AQ110, 322666-701, B1810113.
• OEM vs Generic: OEM transformers are wound to exact VA and voltage tolerances required by the Carrier IFC control board. Undersized or off-tolerance aftermarket transformers can sag under load, causing random lockouts, nuisance board faults, or premature transformer burnout.
• Install Difficulty: 2/5 — Shut off power at the disconnect and breaker before touching any wiring. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (verify 24V output after install). Photograph all wire connections before disconnecting. Confirm 24V between R and C terminals on the control board after replacement.
• Warranty: 1-year OEM manufacturer warranty. Ships same business day from our warehouse when ordered before 3 PM local time.

Compatibility: Direct OEM replacement for Carrier model PG8UAA048111ACJA gas furnace. This transformer is also compatible across a broad range of Carrier, Bryant, and Payne furnaces sharing the same 40VA 120V-24V specification — verify your unit's data plate before ordering. Not sure it fits? Our HVAC parts specialists verify fitment before you buy. Order today and ship today.