OEM Carrier 40VA Control Transformer 120V–24V (HT01BC116) for Model PG8MAA048110ACJA

This OEM control transformer is the factory-specified replacement for the Carrier PG8MAA048110ACJA gas furnace. It steps down 120V line voltage to the 24V required by the furnace's control board, thermostat circuit, and low-voltage components. When this transformer fails, the entire control circuit loses power — resulting in a completely unresponsive furnace, a blank thermostat display, or an immediate no-heat lockout with no error codes. A blown internal fuse or a shorted secondary winding are the two most common failure modes.

• Specs: 40VA capacity | 120V primary / 24V secondary | 50/60 Hz | Single phase | Wire-lead connection type — matches factory OEM specification exactly
• OEM vs Generic: This OEM unit is wound to Carrier's exact 40VA ±3% tolerance. Undersized or off-tolerance generic transformers can overheat under normal control-circuit loads, tripping thermal cutoffs and causing intermittent no-heat complaints.
• Install difficulty: 2/5 — Shut off the furnace disconnect and confirm 0V at the transformer primary before touching any terminals. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or quick-disconnect terminals. Photograph existing wiring before removal. Note: OEM part number HT01BC116 has been superseded by HT680054 — both designations are fulfilled with the current production unit.
• Warranty: 1-year OEM manufacturer warranty. In-stock units ship same business day from our warehouse when ordered by 3 PM local time.

Compatibility: Direct OEM replacement for Carrier model PG8MAA048110ACJA gas furnace. This transformer also cross-references to multiple Carrier, Bryant, and Payne furnace platforms that share the same 40VA 120/24V control circuit specification. Verify your data plate lists 120V primary and 24V secondary before ordering. Our fitment team is available to confirm compatibility prior to purchase — order with confidence and get your heat back on today.