OEM Carrier Control Transformer 40VA 208/240V to 24V for Model PY3GPAA48090NA

This is the genuine OEM Carrier control transformer (part #HT01BD209) factory-specified for the Carrier PY3GPAA48090NA packaged gas/electric unit. The transformer steps down line voltage (208/240V) to the 24V signal required to power the thermostat, control board, contactor coil, and all low-voltage control circuits. When it fails, the entire control system goes dark — nothing responds, the thermostat goes blank, and the unit will not attempt to heat or cool. A failed transformer is one of the most commonly misdiagnosed HVAC faults; always test it before condemning the control board.

• Specs: 40VA rating | 208/240V primary input | 24V secondary output | 50/60Hz | OEM part #HT01BD209 | Also replaces HT01BD207, HT01CN232, 9076-00
• OEM vs Generic: This OEM unit is factory-wound to exact VA and voltage tolerances. Undersized or off-tolerance generic transformers can overload and fail prematurely, or deliver insufficient voltage to reliably pull in contactors and control relays.
• Install difficulty: 2/5 — Power down and lock out the unit at the disconnect before touching any wiring. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Label and photograph all wiring before disconnecting. Verify 24V output with a meter before buttoning up the panel.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse — order before 3PM local time for same-day dispatch.

Compatibility: Designed as the factory replacement for Carrier model PY3GPAA48090NA packaged gas/electric units. Cross-references OEM part numbers HT01BD207, HT01CN232, and 9076-00. Confirm your unit's primary voltage on the data plate before ordering. Our parts specialists are available to verify fitment before you buy.