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OEM Carrier Contactor 24V Coil 2-Pole for HA1AJX042000AAAA
Carrier

OEM Carrier Contactor 24V Coil 2-Pole for HA1AJX042000AAAA

SKU: CARRIE-HA1AJX042000AAAA-CONTACTOR-HN51KC024 Brand: Carrier
✓ Guaranteed to fit HA1AJX042000AAAA — or your money back. Terms

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier 2-Pole Contactor HN51KC024 for Model HA1AJX042000AAAA

This is the factory OEM replacement contactor for the Carrier HA1AJX042000AAAA split-system air conditioner. The contactor is a high-voltage relay that receives a 24V signal from your thermostat and closes to send 240V line power to the compressor and condenser fan motor. When the contactor fails — due to pitted or burned contacts, a stuck plunger, or a failed coil — your outdoor unit will not energize even when the thermostat is calling for cooling. Common symptoms include a buzzing outdoor unit with no compressor startup, or an outdoor unit that simply does nothing when the thermostat is set below room temperature.

  • Specs: OEM Part Number HN51KC024 | 2-Pole design | 24V control coil | Factory-rated amperage for HA1AJX042000AAAA condenser | Direct drop-in replacement
  • OEM vs Generic: This OEM contactor is manufactured to Carrier's exact coil pull-in voltage and contact rating specifications. Generic contactors may use lower-grade silver alloy contacts that pit faster under load, reducing service life and risking compressor damage.
  • Install Difficulty: 3/5 — Always disconnect power at the disconnect box before servicing. Tools needed: flathead and Phillips screwdrivers, 1/4" and 5/16" nut drivers, needle-nose pliers, multimeter. Photograph all wire connections before removing the old contactor. Wires transfer one-at-a-time to avoid miswiring.
  • Warranty: 1-year OEM factory warranty against defects. Orders placed before cutoff ship same business day from our stocked warehouse.

Compatibility: Engineered specifically for the Carrier HA1AJX042000AAAA condensing unit. Cross-references OEM part number HN51KC024. Verify your existing contactor's pole count, coil voltage, and amperage rating against your unit's data plate before ordering. Not sure if this is the right part? Our HVAC parts specialists confirm fitment before you buy — no guesswork required.

Shipping Information

  • Orders placed before 3PM CST ship same business day
  • Standard delivery: 2-5 business days
  • Express shipping available at checkout
  • Free shipping on orders over $99
  • Tracking number emailed upon shipment

Return Policy

  • 30-day returns on unused parts in original packaging
  • Electrical parts (capacitors, contactors, control boards) are final sale once installed
  • Email info@nationalhvacparts.com to initiate a return
  • Refunds processed within 5-7 business days

Frequently Asked Questions

Does this Contactor fit my Carrier HA1AJX042000AAAA?
Yes. This is the factory-specified OEM contactor for the Carrier HA1AJX042000AAAA. It is a direct drop-in replacement that fits without modification. Always verify the model number on your equipment nameplate before ordering.
How do I replace the contactor on my Carrier HA1AJX042000AAAA?
Difficulty: Medium (30–45 min)
Step 1: Turn off breaker. Step 2: Open condensing unit panel. Step 3: Photograph ALL wiring on the contactor. Step 4: Label each wire with tape. Step 5: Disconnect wires and remove old contactor. Step 6: Mount new contactor, reconnect wires matching your photo. Step 7: Restore power and test.
My AC clicks but the compressor won’t turn on. What’s wrong?
Clicking from the outdoor unit without the compressor starting = worn contactor. The contactor sends power to the compressor. When its contacts are pitted, it clicks but can’t make solid contact. Look for: visible pitting/burn marks on the contactor face, intermittent operation, or buzzing.
Is this contactor compatible with Bryant or Payne too?
Many Carrier parts are cross-compatible with Bryant and Payne since all three brands are manufactured by Carrier Global Corporation. The same physical part is often used across brand labels with different model numbers. To verify: check your Bryant or Payne equipment service manual for cross-compatible part numbers, or email info@nationalhvacparts.com with your model number.
Should I use OEM or aftermarket for my Carrier contactor?
OEM recommended for reliability and warranty compatibility. OEM parts match exact factory specifications for proper fit, performance, and safety. While aftermarket alternatives cost less upfront, the risk of improper fit and reduced lifespan usually makes OEM the better value long-term.
How fast does National HVAC Parts ship?
Orders placed before 3:00 PM CST ship the same business day. Standard delivery is 2–5 business days anywhere in the continental United States. Express shipping available at checkout. We ship from Houston, TX to all 50 states. 30-day return policy on all parts.
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Mike Rivera
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