OEM Carrier Furnace Transformer 120V–24V 40VA for Model PG9MAB060120AASA

This OEM control circuit transformer is the factory-specified replacement for the Carrier PG9MAB060120AASA gas furnace. It steps down the 120V line voltage to 24V AC, powering every low-voltage component in your system — the thermostat, control board, gas valve, and zone controls. When this transformer fails, the entire furnace goes silent: no fan, no ignition, no response from the thermostat. If you're measuring 0V between the R and C terminals on your control board, this transformer is the most likely culprit.

• Specs: Input 120V AC | Output 24V AC | 40VA rating | 60Hz | Foot-mount configuration | Wire lead connections with pre-installed insulated female connectors
• OEM vs Generic: This is a factory OEM part (superseded to HT680054), manufactured to exact Carrier tolerances. Generic transformers frequently carry incorrect VA ratings or mismatched mounting footprints, leading to difficult installation and shortened service life — as confirmed by field technicians who found generic units would not mount correctly without modification.
• Install Difficulty: 2/5 — Always shut off power at the breaker and verify zero voltage before disconnecting wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, needle-nose pliers. Photograph all wire connections before removal. Verify 24V output at R-C terminals after installation.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Fits Carrier model PG9MAB060120AASA gas furnaces. OEM part number HT01BC116, superseded by HT680054. Also cross-references HT01BC115, HT01BC120, HT01BB126, HT01CT120, and several other legacy Carrier/Bryant/Payne transformer part numbers. Always verify your unit's data plate voltage requirements before ordering. Our fitment team is available to confirm compatibility before you buy.