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OEM Carrier Contactor 24V 2-Pole for HB1AJX030000AAAA — HN51KB024
Carrier

OEM Carrier Contactor 24V 2-Pole for HB1AJX030000AAAA — HN51KB024

SKU: CARRIE-HB1AJX030000AAAA-CONTACTOR-HN51KB024 Brand: Carrier

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier 2-Pole Contactor 24V Coil for Model HB1AJX030000AAAA

This is the factory OEM replacement contactor (part number HN51KB024) for the Carrier HB1AJX030000AAAA air conditioning system. The contactor is the high-voltage relay that receives a 24V signal from your thermostat and closes the circuit to send line voltage to the compressor and condenser fan motor. When the contactor fails — through burned or pitted contacts, a stuck plunger, or a failed coil — the system will fail to energize entirely, leaving you with a unit that hums, clicks repeatedly, or does nothing at all when cooling is called for.

  • Specs: 2-pole configuration | 24V AC coil voltage | Rated for single-phase compressor and fan motor loads | OEM part number HN51KB024 | Factory-matched contact material and coil resistance
  • OEM vs Generic: OEM contactors use factory-spec silver-alloy contact surfaces that resist pitting and arcing far longer than generic alternatives. A mismatched coil resistance can cause chatter, overheating, or nuisance tripping — OEM eliminates that risk entirely.
  • Install difficulty: 2/5 — Disconnect power at the disconnect box and verify with a non-contact voltage tester before touching any wiring. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all wiring connections before removal. One screw terminal at a time — never work live on high-voltage terminals.
  • Warranty: 1-year OEM factory warranty against defects. Orders placed before cutoff ship same business day from our climate-controlled warehouse.

Compatibility: Engineered specifically for the Carrier HB1AJX030000AAAA system. Always cross-reference the OEM part number HN51KB024 and verify coil voltage and pole configuration on your unit's data plate before ordering. Our HVAC parts specialists are available to confirm fitment — contact us before you order if you have any questions. In stock and ships 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 $75
  • 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 HB1AJX030000AAAA — HN51KB024?
Yes. This is the factory-specified OEM contactor for the Carrier HB1AJX030000AAAA — HN51KB024. 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 HB1AJX030000AAAA — HN51KB024?
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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