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OEM Carrier Contactor 24V Coil 2-Pole for HA1BJX018000AAAA
Carrier

OEM Carrier Contactor 24V Coil 2-Pole for HA1BJX018000AAAA

SKU: CARRIE-HA1BJX018000AAAA-CONTACTOR-HN51KB024 Brand: Carrier
✓ Guaranteed to fit HA1BJX018000AAAA — or your money back. Terms

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier Contactor HN51KB024 for Model HA1BJX018000AAAA

This OEM contactor (part number HN51KB024) is the factory-specified high-voltage relay for the Carrier HA1BJX018000AAAA air handler and connected condensing system. The contactor acts as the primary switching relay between your 24V thermostat control signal and the high-voltage compressor and condenser fan circuits. When it fails — due to pitted contacts, burned terminals, or a stuck plunger — the most common symptom is an air conditioning system that simply won't turn on despite the thermostat calling for cooling. You may also notice the unit runs continuously without shutting off, or hear a loud buzzing or chattering from the contactor itself.

  • Specs: 2-pole configuration | 24V AC coil voltage | Factory-rated amperage for HA1BJX018000AAAA application | OEM part number HN51KB024 | Direct drop-in replacement with matching terminal layout
  • OEM vs Generic: OEM contactors feature silver-alloy contact tips rated for the exact load cycles of your Carrier system. Generic contactors often use inferior contact materials that pit and weld faster under compressor inrush current, leading to premature failure and potential compressor damage.
  • Install difficulty: 2/5 — Always shut off power at the disconnect and breaker before beginning. Tools needed: 1/4" and 5/16" nut drivers, flathead screwdriver, needle-nose pliers, multimeter. Photograph all wiring connections before removing the old contactor, and transfer wires 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: Designed as a direct OEM replacement for the Carrier HA1BJX018000AAAA. Verify coil voltage (24V) and pole configuration on your existing unit's data plate or wiring diagram before ordering. Our HVAC parts specialists are available to confirm fitment — contact us before you buy if you have any questions. In stock and ready to ship today.

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 HA1BJX018000AAAA?
Yes. This is the factory-specified OEM contactor for the Carrier HA1BJX018000AAAA. 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 HA1BJX018000AAAA?
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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