OEM Carrier Furnace Transformer 120V–24V 40VA for Model PG8UAA036065ABJA

This OEM control circuit transformer is the factory-specified replacement for the Carrier PG8UAA036065ABJA gas furnace. Originally sold under part number HT01BC116, this transformer has been updated by Carrier to the current OEM replacement HT680054 — a direct, drop-in swap with no modifications required. The transformer steps down 120V line voltage to 24V AC, powering every low-voltage component in your furnace: the thermostat circuit, control board, gas valve, and inducer relay. When it fails, the entire control circuit goes dead — your furnace will not respond to the thermostat, and no heating cycle can begin. Diagnosing a bad transformer is straightforward: check for 24V between the R and C terminals on the control board; a reading of 0V with 120V confirmed at primary input points directly to transformer failure.

• Specs: Primary input 120V AC | Secondary output 24V AC | 40VA rating | 60 Hz | Wire lead connections | Foot-mount style | Includes 3A fuse protection
• OEM vs Generic: OEM transformers are wound to exact VA tolerances, ensuring stable 24V output under full load. Generic units often underperform at rated VA, causing nuisance lockouts, erratic thermostat response, and premature control board failure.
• Install difficulty: 2/5 — Shut off power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire connectors. Photograph existing wiring before disconnecting. Match primary and secondary wire leads to original terminations.
• Warranty: 1-year OEM factory warranty on parts. Orders ship same business day from our stocked warehouse.

Compatibility: Factory-matched for the Carrier PG8UAA036065ABJA gas furnace. Also cross-references HT01BC115, HT01BB126, HT01CT120, HT01BC120, and HT01AW115 for extended model coverage. Verify 120V primary input on your unit's data plate before ordering. Our parts specialists are standing by to confirm fitment before you buy — ships today!