What amp contactor do I need for my Lennox system?

The correct replacement for Lennox model OEM Lennox Contactor SPST 30A 24V — 51X76 is this exact part. It is the factory-specified replacement with exact OEM specifications. Using a part with different specifications can cause equipment damage or void your warranty. You can verify this by checking the data plate on your Lennox equipment which lists the model number OEM Lennox Contactor SPST 30A 24V — 51X76.

My AC clicks but the compressor does not turn on. What is wrong?

Clicking from the outdoor unit without the compressor starting usually means a worn contactor. The contactor is the relay that sends power to the compressor. When its contacts are pitted or worn, it clicks but cannot establish a solid electrical connection. Other symptoms: visible pitting or burn marks on the contactor face, AC works intermittently, or buzzing from the contactor.

Lennox

OEM Lennox Contactor SPST 30A 24V — 51X76

Name: OEM Lennox Contactor SPST 30A 24V — 51X76
Brand: Lennox
SKU: LNX-51X76
Price: 28.95 USD
Availability: InStock

SKU: LNX-51X76 Brand: Lennox

$28.95 $38.95

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The genuine OEM Lennox 51X76 (DP1030A5014/U) is a single-pole, single-throw (SPST) contactor rated at 30 amps with a 24-volt control coil. This definite-purpose contactor switches power to the compressor and fan motor in your Lennox condensing unit, closing whenever the low-voltage control circuit calls for cooling and reliably managing the motor's inrush and running current.

Common failure symptoms: When the 51X76 fails, typical signs include an outdoor unit that hums but won't start, a buzzing or chattering contactor, and contacts that are pitted, corroded, or burnt. Welded contacts can keep the compressor running continuously, while a bad 24V coil may prevent the contactor from pulling in at all, leaving you with no cooling on a hot day.

Why OEM matters: The Lennox 51X76 is built to the precise 24V coil voltage and 30-amp contact rating your system requires. Installing a non-OEM contactor with a mismatched coil or lower rating can cause chatter, overheating, and early failure that stresses your compressor. The correct factory part guarantees proper fit, reliable operation, and full rated service life for your Lennox equipment.

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

OEM Lennox Contactor SPST 30A 24...

$28.95

Frequently Asked Questions

Does this Contactor fit my Lennox OEM Lennox Contactor SPST 30A 24V — 51X76?

Yes. This is the factory-specified OEM contactor for the Lennox OEM Lennox Contactor SPST 30A 24V — 51X76. 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 Lennox OEM Lennox Contactor SPST 30A 24V — 51X76?

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 Lennox 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 Lennox 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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OEM Lennox Contactor SPST 30A 24V — 51X76

Shipping Information

Return Policy

Frequently Asked Questions