OEM Carrier Furnace Control Transformer 120V–24V 40VA for Model PG8MAA036045ADJA

This OEM control transformer (part number HT01BC116, updated to HT680054) is the factory-specified replacement for the Carrier PG8MAA036045ADJA gas furnace. The transformer steps down 120V line voltage to 24V AC, powering every low-voltage component in the system — thermostat, gas valve, inducer relay, and control board. When it fails, the furnace goes completely dark: no thermostat response, no ignition attempt, and no fan operation. A failed transformer is one of the most common causes of a completely unresponsive furnace.

• Specs: Input 120V AC | Output 24V AC | 40VA rating | Foot-mount configuration | Wire lead connections | 60 Hz
• OEM vs Generic: OEM transformers are wound to exact Carrier factory tolerances, ensuring stable 24V output under full load. Generic units often undervolt the control circuit, causing random lockouts, false pressure switch trips, and premature control board failure.
• Install Difficulty: 2/5 — Shut off power at the breaker and confirm zero voltage before proceeding. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Label or photograph all wire connections before removing the old transformer. Verify 24V output at the R and C terminals after installation.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Fits Carrier model PG8MAA036045ADJA gas furnace. Note: OEM part number HT01BC116 has been superseded by HT680054 — both are the same 120V–24V 40VA transformer and are fully interchangeable. Always verify input voltage and VA rating on your unit's data plate before ordering. Our team is happy to confirm fitment prior to purchase.