OEM Carrier Control Transformer 40VA 208/230V to 24V for Model PY3PNA048090NB

This is the genuine OEM Carrier control transformer (part #HT01BD209) factory-specified for the Carrier PY3PNA048090NB packaged unit. The transformer steps down 208/230V line voltage to the 24V DC signal that powers your thermostat, control board, contactors, and all low-voltage control wiring. When this component fails, the entire control circuit goes dead — your thermostat goes blank, the system won't respond to any call for heating or cooling, and nothing turns on. A failed transformer is one of the most common reasons an otherwise healthy HVAC system appears completely unresponsive.

• Specs: 40VA capacity | 208/230V primary input | 24V secondary output | 50/60 Hz rated | OEM part number HT01BD209 | Replaces HT01BD207, HT01CN232, 9076-00
• OEM vs Generic: The OEM HT01BD209 is factory-wound to exact impedance and VA tolerances for the PY3PNA048090NB. Generic alternatives may run slightly under-rated VA, causing the transformer to overheat under simultaneous thermostat + contactor + board load — leading to premature failure and blown fuses.
• Install difficulty: 2/5 — Disconnect power at the breaker and verify with a multimeter before touching any wiring. Photograph all wire connections before removal. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Check the 3A control-circuit fuse on the board before condemning the transformer — a shorted low-voltage device can blow both.
• Warranty: 1-year OEM manufacturer warranty. Ships same business day from our warehouse when ordered by 3PM local time.

Compatibility: Engineered as the factory-direct replacement for the Carrier PY3PNA048090NB packaged unit. Also compatible with select Bryant and Payne models sharing the same 40VA 208/230V transformer specification — verify your unit's data plate before ordering. Questions about fitment? Our HVAC parts specialists confirm compatibility before you buy. Order now — in stock and ships today.