OEM Carrier Transformer HT01BD209 40VA 120V/24V for Model PY3GNA030060AB

This OEM control-circuit transformer is the factory-specified replacement for the Carrier PY3GNA030060AB. Its sole but critical job is to step down 120V line voltage to the 24V signal voltage that powers your thermostat, control board relays, and every other low-voltage component in the system. When this transformer fails, the entire control circuit goes dark — no thermostat response, no ignition sequence, no fan operation. If your system is completely unresponsive and you've already confirmed power at the unit, a failed transformer is the first thing to test.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD209 | Factory-matched for Carrier PY3GNA030060AB
• OEM vs Generic: This is a genuine OEM Carrier transformer, wound and rated to exact factory specifications. Generic transformers often use undersized cores that run hot under full VA load, shortening service life and risking nuisance trips on your overcurrent protection.
• Install difficulty: 2/5 — Always shut off power at the disconnect and confirm voltage is absent with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter, wire nuts or spade connectors. Photograph existing wiring before disconnecting. Primary and secondary leads must go to the correct terminals — reversing them will damage downstream components.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before 3 PM local time.

Compatibility: Engineered specifically for the Carrier PY3GNA030060AB. Confirm the 40VA, 120V primary / 24V secondary specification on your unit's data plate before ordering. Not sure if this part fits your unit? Our HVAC parts specialists verify fitment before you order — contact us and we'll confirm within minutes.