OEM Carrier Control Transformer 40VA 120V–24V for Model PG9MAA024040AFKA (Replaces HT01BC116)

This OEM step-down control transformer is the factory-specified replacement for the Carrier PG9MAA024040AFKA gas furnace. The transformer converts 120V line voltage down to the 24V signal voltage that powers your thermostat, control board, gas valve, and all low-voltage control circuits. When it fails, the furnace goes completely silent — no ignition attempt, no thermostat response, no fan activity. If your 24V fuse keeps blowing or your system is completely unresponsive, a failed transformer is one of the first components to test.

• Specs: 40VA capacity | 120V primary / 24V secondary | 50/60 Hz single-phase | Wire lead connections | Replaces OEM part number HT01BC116 (superseded by HT680054)
• OEM vs Generic: This OEM unit is wound to Carrier's exact VA and impedance tolerances. Generic transformers frequently run under-rated, causing nuisance fuse failures and erratic thermostat behavior — especially in variable-speed or two-stage furnace control circuits.
• Install difficulty: 2/5 — Turn off all power at the breaker before starting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24V output post-install). Photograph wiring connections before removal. Note: discharge any residual voltage before handling terminals.
• Warranty: 1-year OEM manufacturer warranty. In-stock units ship the same business day from our warehouse.

Compatibility: Engineered as a direct OEM drop-in replacement for Carrier model PG9MAA024040AFKA gas furnaces. Also replaces legacy part numbers HT01BC116, HT01BC115, HT01BB126, HT01CT120, and several other Carrier/Bryant/Payne transformer variants — verify primary voltage (120V) and VA rating (40VA) against your unit's data plate before ordering. Order before 5 PM and your part ships today.