OEM Carrier Furnace Control Transformer 40VA 120V-24V for Model PG8JAA048135AAJA

This OEM step-down transformer is the factory-specified replacement for the Carrier PG8JAA048135AAJA gas furnace. It converts 120V line voltage down to 24V AC to power the low-voltage control circuit — including the thermostat, control board, gas valve, and inducer relay. When this transformer fails, absolutely nothing in the furnace will respond: no ignition attempt, no error codes, no thermostat communication. It is one of the first components to test whenever a furnace appears completely dead.

• Specs: 40VA rating | 120V primary | 24V secondary | 60 Hz single-phase | Foot-mount configuration | Wire lead connection type with insulated female quick-connect terminals
• OEM vs Generic: This is a genuine OEM Carrier transformer (superseded part HT680054, direct replacement for HT01BC116) shipped in factory-authorized packaging. OEM units are wound to exact VA and voltage tolerances. Generic transformers often run hot under load and can damage sensitive control boards over time.
• Install difficulty: 2/5 — Shut off power at the breaker and verify zero voltage before touching any wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, needle-nose pliers. Photograph all wire connections before disconnecting the old unit. Verify 24V output at the R and C terminals on the control board after installation.
• Warranty: 1-year OEM manufacturer warranty. In-stock units ship same business day from our warehouse when ordered by 5 PM local time.

Compatibility: Engineered as a direct OEM replacement for Carrier model PG8JAA048135AAJA. This transformer also supersedes legacy part numbers HT01BC116, HT01BC115, HT01BB126, HT01CT120, HT01BC120, HT01AW115, and several others — making it a broad-coverage OEM solution for Carrier, Bryant, and Payne furnaces sharing this control circuit specification. Confirm your unit's data plate shows a 120V primary / 24V secondary transformer requirement before ordering. Not sure? Our team verifies fitment before you buy — reach out before placing your order.