OEM Carrier Single-Pole Contactor 25A 24V Coil (HN51KB024) for Model PY3GNA024040AB

This is the genuine OEM Carrier contactor (part number HN51KB024), factory-specified for the Carrier PY3GNA024040AB packaged unit. The contactor is a high-voltage relay that closes the circuit to the compressor and/or condenser fan motor when the thermostat calls for cooling. When the contactor fails — due to burnt or pitted contacts, a failed coil, or a mechanically stuck plunger — the most common symptom is the outdoor unit not energizing at all, even when the thermostat is set correctly and the indoor air handler is running. A failed contactor can also cause the compressor to run continuously (welded contacts) or to short-cycle, both of which accelerate system wear.

• Specs: 1 Pole (Single Pole) | 25A Full Load Amps (FLA) | 150A Locked Rotor Amps (LRA) | 24V AC 50/60 Hz coil | OEM-matched contact geometry and coil resistance
• OEM vs Generic: OEM contactors use factory-spec silver-alloy contacts rated for tens of thousands of switching cycles. Generic aftermarket contactors often use lower-grade contacts that pit and weld prematurely, leading to repeat failures within one season.
• Install difficulty: 2/5 — Always shut off power at both the breaker and the disconnect box before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all wiring connections before removing the old contactor. Discharge any residual voltage and verify 0V before touching terminals.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse on all in-stock orders.

Compatibility: Direct OEM replacement for Carrier model PY3GNA024040AB. Verify your unit's data plate confirms a single-pole contactor before ordering. Not sure? Our fitment team will confirm compatibility before you buy — no guesswork required.