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OEM Carrier Contactor 1-Pole 30A 24V for PH4ZNA042000AA
Carrier

OEM Carrier Contactor 1-Pole 30A 24V for PH4ZNA042000AA

SKU: CARRIE-PH4ZNA042000AA-CONTACTOR-HN51KC024 Brand: Carrier
✓ Guaranteed to fit PH4ZNA042000AA — or your money back. Terms

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier 1-Pole Contactor 30 Amp 24V Coil for Model PH4ZNA042000AA (HN51KC024)

This is the factory-authorized OEM replacement contactor for the Carrier PH4ZNA042000AA heat pump system. The contactor is the high-voltage relay that receives a low-voltage (24V) signal from your thermostat and closes the circuit to power the compressor and/or condenser fan motor. When the contactor fails — due to pitted or burned contacts, a welded-shut plunger, or an open coil — the most common symptoms are an AC or heat pump that won't turn on at all, a unit that runs constantly without shutting off, or a compressor that hums but fails to start. Replacing a failed contactor restores full system operation and protects your compressor from additional damage.

  • Specs: 1-Pole | 24 VAC Coil Voltage | 30A Full Load Amps (FLA) | 150A Locked Rotor Amps (LRA) | 50/60 Hz | OEM Part# HN51KC024
  • OEM vs Generic: This is a genuine Carrier Factory Authorized Part built to exact factory tolerances. Generic contactors often use lower-grade contact materials that pit and weld faster under compressor load — OEM ensures the correct pull-in voltage, contact gap, and contact silver-alloy rating for long service life.
  • Install Difficulty: 2/5 — Shut off power at the disconnect and breaker before opening the unit. Photograph all wiring before disconnecting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, non-contact voltage tester. Verify 24V coil pull-in after installation with a thermostat call for cooling.
  • Warranty & Shipping: Backed by a 1-year OEM factory warranty. In-stock and ships same business day from our warehouse — get your system back up fast.

Compatibility: Engineered for the Carrier PH4ZNA042000AA heat pump. Always confirm the OEM part number on your unit's wiring diagram or data plate matches HN51KC024 before ordering. Our HVAC parts team is available to verify fitment if you have any questions before you buy.

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 PH4ZNA042000AA?
Yes. This is the factory-specified OEM contactor for the Carrier PH4ZNA042000AA. 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 PH4ZNA042000AA?
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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