OEM Carrier 1-Pole Contactor 24V 25 Amp for Model PY3PNA030040AB — HN51KB024

This is the genuine OEM Carrier contactor (part #HN51KB024) factory-specified for the Carrier PY3PNA030040AB packaged unit. The contactor is the high-voltage switching relay that energizes the compressor and/or condenser fan motor every time your thermostat calls for cooling. When the 24V coil receives a signal from the control board, the contactor closes its contacts to pass line voltage to the load. When it fails, symptoms include the system humming but not starting, the unit refusing to shut off (welded contacts), chattering or buzzing noises from the electrical compartment, or a completely dead outdoor unit despite a valid thermostat call.

• Specs: 1-Pole | 24V AC 50/60Hz Coil | 25 FLA (Full Load Amps) | Definite purpose contactor | OEM Part #HN51KB024
• OEM vs Generic: This factory OEM contactor is built to exact Carrier tolerances for coil pull-in voltage, contact gap, and arc suppression. Generic aftermarket contactors often use lower-grade silver alloy contacts that pit and weld prematurely, leading to callback failures within one season.
• Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all wiring before disconnecting any terminals. Verify coil voltage with a multimeter before condemning the contactor.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before cutoff.

Compatibility: Fits Carrier model PY3PNA030040AB packaged unit as the factory-specified single-pole contactor. Always cross-reference your unit's data plate and wiring diagram to confirm pole count, coil voltage, and amperage before ordering. Our team is available to verify fitment — contact us before you buy if you have any questions. Order today for same-day shipping.