OEM Carrier 1-Pole 25 Amp Contactor (HN51KB024) for Model PY3GNA030040AA

This OEM contactor is the factory-specified replacement for the Carrier PY3GNA030040AA condensing unit. The contactor acts as the high-voltage relay in your system's control circuit: when the thermostat calls for cooling, the 24V coil energizes and closes the contact points, sending line voltage to the compressor and condenser fan motor. A failed contactor typically results in the outdoor unit failing to respond to the thermostat call, a humming compressor that won't start, or — in the case of welded/pitted contacts — a unit that runs continuously and won't shut off.

• Specs: 1-Pole configuration | 25 Amp load rating | 24V AC coil voltage | OEM part number HN51KB024 | Factory-matched contact grade and coil resistance
• OEM vs Generic: This is a genuine Carrier OEM contactor. Generic aftermarket contactors often use lower-grade contact alloys that pit and weld faster under high-cycle loads — especially in hot climates. OEM ensures factory coil pull-in voltage and contact gap specifications are met.
• Install Difficulty: 2/5 — Always disconnect power at the disconnect box and verify zero voltage with a multimeter before touching terminals. Photograph all wiring before removal. Tools needed: flathead screwdriver, needle-nose pliers, multimeter. Swap line, load, and coil leads one at a time to avoid miswiring.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse — get your system back online fast.

Compatibility: Designed for Carrier model PY3GNA030040AA. Verify OEM part number HN51KB024 against your unit's wiring diagram or parts list before ordering. Our fitment team is available to confirm compatibility — don't hesitate to reach out before you buy.