OEM Carrier 40VA Furnace Control Transformer 120V–24V for Model PG8JAA036110ABJA

This is the factory-specified OEM step-down control transformer for the Carrier PG8JAA036110ABJA gas furnace. The transformer converts 120V line voltage down to 24V AC to power all low-voltage control circuit components — including the thermostat, gas valve, and control board. When the transformer fails, the entire control circuit goes dead: the thermostat goes blank, no call for heat is possible, and nothing in the system responds. A blown transformer is also often a symptom of a short elsewhere in the low-voltage wiring, so inspecting the full 24V circuit before replacing is strongly recommended.

• Specs: 40VA rating | 120V primary / 24V secondary | 60 Hz single-phase | Wire lead connection type | Compact foot-mount housing approx. 3" L × 2-3/16" W × 2" H
• OEM vs Generic: This OEM transformer is wound to exact Carrier factory tolerances, ensuring stable 24V output under load. Generic alternatives frequently deliver under-voltage at higher amperage draws, stressing the control board and shortening system life. OEM is the only recommended choice for 24V circuits powering gas valves and variable-speed boards.
• Install difficulty: 2/5 — Shut off power at the breaker and confirm zero voltage before touching any wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, needle-nose pliers. Before disconnecting, photograph all wire connections. Check for any short circuits in the 24V wiring (thermostat wires, gas valve leads) before energizing the new transformer — an unresolved short will blow the replacement immediately.
• Warranty & Shipping: 1-year OEM manufacturer warranty. In stock and ships same business day from our warehouse when ordered before cutoff.

Compatibility & Part Supersession: Fits Carrier PG8JAA036110ABJA gas furnaces. OEM part number HT01BC116 has been factory-superseded by updated part number HT680054 — a direct drop-in replacement supplied in a Carrier factory-authorized parts box. Also replaces HT01BC115, HT01BB126, HT01CT120, HT01BC120, and multiple legacy part numbers. Verify your unit's data plate voltage specifications before ordering. Our team is available to confirm fitment — reach out before you buy.