OEM Carrier Control Transformer 40VA 208/230V to 24V — Model PY3GNA048090AA

This is the genuine OEM control transformer for the Carrier PY3GNA048090AA packaged unit, carrying OEM part number HT01BD209. The transformer steps down line voltage from 208/230V to 24V to power the entire low-voltage control circuit — including the thermostat, contactor coil, gas valve, and control board. When the transformer fails, the result is total loss of control power: a completely unresponsive thermostat, a system that won't heat or cool, and no 24V signal anywhere in the circuit. It's one of the first components to check when nothing works at all.

• Specs: 208/230V primary | 24V secondary | 40VA rated | 50/60Hz | Replaces HT01BD207, HT01CN232, and 9076-00
• OEM vs Generic: OEM transformers are wound to Carrier's exact VA and insulation class, preventing voltage sag under full control-circuit load. Generic units may underperform at rated VA, causing nuisance lockouts and premature failure of downstream components.
• Install difficulty: 2/5 — Shut off power at the disconnect and verify 0V with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade terminals. Photograph all existing wiring connections before removal.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse — order before 3PM for same-day dispatch.

Compatibility: Directly fits Carrier model PY3GNA048090AA. Also compatible with Bryant and Payne units sharing this transformer specification. Always verify your unit's data plate voltage and VA rating before ordering — our fitment team is available to confirm compatibility before you buy.