OEM Carrier Contactor 2-Pole 24V Coil for Model HA1AJX030000AAAA

This is the factory OEM replacement contactor (part number HN51KB024) for the Carrier HA1AJX030000AAAA air handler and associated condensing equipment. The contactor is the high-voltage relay that bridges your 24V thermostat control signal to the 240V compressor and condenser fan circuits. When the thermostat calls for cooling, the contactor's coil energizes and closes the power contacts — allowing the system to run. A failed contactor is one of the most common reasons an AC system won't respond to a cooling call, produces a loud buzzing or chattering sound, or runs continuously without shutting off. Pitted, burned, or stuck contacts are telltale signs this part needs replacement.

• Specs: 2-pole configuration | 24V coil voltage | Factory-rated contact amperage | Direct OEM replacement for part number HN51KB024
• OEM vs Generic: OEM contactors use factory-spec contact materials and coil windings, ensuring proper pull-in voltage and long contact life. Generic substitutes often use lower-grade contacts that pit faster under load cycling, leading to premature failure.
• Install Difficulty: 2/5 — Always shut off power at the disconnect and verify zero voltage with a multimeter before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all wiring connections before removing the old contactor to ensure correct reinstallation.
• Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship same business day from our stocked warehouse.

Compatibility: Engineered specifically for the Carrier HA1AJX030000AAAA unit. Always confirm your existing contactor's pole count, coil voltage, and amperage rating against your unit's data plate before ordering. Our HVAC parts specialists are available to verify fitment — reach out before you order if you have any questions. In stock and ready to ship today.