What amp contactor do I need for my Lennox system?

The correct replacement for Lennox model OEM Lennox Contactor DPST 40A 24V Coil — 24N34 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 DPST 40A 24V Coil — 24N34.

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 DPST 40A 24V Coil — 24N34

Name: OEM Lennox Contactor DPST 40A 24V Coil — 24N34
Brand: Lennox
SKU: LNX-24N34
Price: 28.95 USD
Availability: InStock

SKU: LNX-24N34 Brand: Lennox

$28.95 $38.95

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The Lennox 24N34 (OEM equivalent DP2040A5004/U) is a genuine double-pole, single-throw contactor rated at 40 amps with a 24-volt coil. This DPST contactor is the workhorse switch inside your Lennox condensing unit, closing two poles of line voltage to the compressor and outdoor fan motor each time the thermostat calls for cooling and the 24V coil pulls the contacts in.

Common failure symptoms include an air conditioner that hums but won't start, a condenser fan and compressor that stay running after the cooling demand ends (welded contacts), audible chatter at the outdoor unit, and burnt, pitted, or corroded contact surfaces. Ant infestation and moisture-driven corrosion are frequent causes of a stuck or non-pulling contactor.

The OEM 24N34 matters because Lennox specifies the exact 24V coil, 40A contact rating, and terminal configuration for a safe, direct replacement. Aftermarket contactors with slightly different dimensions or coil resistance can cause chatter, premature wear, and compressor stress. Restore dependable, factory-rated switching with the genuine Lennox part.

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 DPST 40A 24...

$28.95

Frequently Asked Questions

Does this Contactor fit my Lennox OEM Lennox Contactor DPST 40A 24V Coil — 24N34?

Yes. This is the factory-specified OEM contactor for the Lennox OEM Lennox Contactor DPST 40A 24V Coil — 24N34. 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 DPST 40A 24V Coil — 24N34?

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 DPST 40A 24V Coil — 24N34

Shipping Information

Return Policy

Frequently Asked Questions