OEM Carrier Control Transformer 40VA 208/240V to 24V for Model PY3GNA024060AA

This OEM Carrier control transformer (part number HT01BD209) is the factory-specified replacement for the Carrier PY3GNA024060AA HVAC system. Its sole job is to step down the 208/240V line voltage to the safe 24V signal that powers your thermostat, control board, and every low-voltage component in the system. When this transformer fails — due to electrical surges, short circuits in control wiring, or simple wear — the entire system goes dark: the thermostat loses power, the unit refuses to respond to calls for heating or cooling, and you may hear a faint buzzing or humming from the transformer housing itself.

• Specs: 208/240V primary | 24V secondary | 40VA rating | 50/60 Hz | Direct OEM replacement for Carrier PY3GNA024060AA
• Also Replaces: HT01BD207, HT01CN232, 9076-00 — this part supersedes all earlier Carrier control transformer revisions listed above.
• OEM vs Generic: OEM transformers are wound and insulated to exact factory tolerances, ensuring a full 24V output under load. Undersized or off-spec generic units can sag below 24V, causing nuisance lockouts, erratic control board behavior, and premature component failure.
• Install Difficulty: 2/5 — Shut off all power at the disconnect and breaker before touching any wiring. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Photograph all wire connections before disconnecting. Verify 24V output with a multimeter after installation before closing the panel.
• Warranty: 1-year OEM factory warranty against manufacturing defects. Ships same business day from our warehouse when ordered before cutoff.

Compatibility: Designed for the Carrier PY3GNA024060AA. Verify your unit's data plate shows a 208/240V primary control circuit before ordering. If you are unsure whether this part fits your specific serial number or configuration, contact our team — we verify fitment before you buy. Order now and get same-day shipping on all in-stock OEM Carrier parts.