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Lennox

OEM Lennox Heat Exchanger Assembly — 14K71

SKU: LNX-14K71 Brand: Lennox
$399.95 $549.95

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Texas CMBL #19328542014
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Govt POs Accepted

The Lennox 14K71 is a genuine OEM heat exchanger assembly (factory reference 612983-12) engineered for Lennox gas furnaces. This part is where combustion heat is transferred into the air stream that warms your home, while its sealed cells keep flue gases and carbon monoxide safely isolated from indoor air. Produced to exact Lennox specifications, the 14K71 delivers the proper heat transfer area, airflow, and structural integrity your furnace relies on for safe, efficient operation.

Common failure symptoms: A deteriorating heat exchanger typically shows visible cracks, rust, or scaling, a burner flame that dances or rolls out when the blower starts, soot buildup, popping or rumbling noises during heating cycles, and recurring high-limit lockouts. The most urgent warning is a carbon monoxide alarm — if it sounds, shut the furnace down and have the exchanger inspected right away.

Why OEM matters: Because a heat exchanger directly affects combustion safety, only the genuine Lennox 14K71 will do. OEM parts are built to the precise tolerances, alloy, and pressure ratings of the original component, ensuring a tight seal, correct airflow, and full rated efficiency. Non-OEM substitutes risk poor sealing and hazardous leaks, so always install the factory-authentic Lennox assembly.

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 Heat Exchanger fit my Lennox OEM Lennox Heat Exchanger Assembly — 14K71?
Yes. This is the factory-specified OEM heat exchanger for the Lennox OEM Lennox Heat Exchanger Assembly — 14K71. 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 heat exchanger on my Lennox OEM Lennox Heat Exchanger Assembly — 14K71?
Refer to your equipment service manual for model-specific steps. General approach: turn off power, photograph connections, remove old part, install new part, restore power and test. For gas components, hire a licensed technician. Email info@nationalhvacparts.com for guidance.
What symptoms mean I need a new heat exchanger?
Common symptoms: unusual noises, intermittent operation, complete failure, or visible damage. Visit our diagnostic hub for symptom-based troubleshooting.
Is this heat exchanger 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 heat exchanger?
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
HVAC Parts Specialist — Online