Same-day shipping before 3PM CST · 35,000+ OEM Parts · Texas CMBL & SAM.gov Registered · Government POs Accepted

Menu

Home Shop All Account Cart

IMAGE COMING SOON

Lennox

OEM Lennox Stainless Steel Heat Exchanger — 19A74

SKU: LNX-19A74 Brand: Lennox
$399.95 $549.95

OEM Guaranteed

Same-Day Ship

30-Day Returns

Secure Checkout

Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

The genuine OEM Lennox 19A74 stainless steel heat exchanger assembly delivers the durability and corrosion resistance your Lennox furnace was designed around. Its stainless construction transfers combustion heat to your home's air stream efficiently while resisting the acidic condensate and thermal fatigue that shorten the life of lesser materials. This assembly keeps combustion gases isolated from your breathing air, making it a critical safety component.

Common failure symptoms include cracks, pinholes, or rust perforations in the exchanger, a burner flame that distorts when the blower starts, soot accumulation, unusual odors, and carbon monoxide alarms. Because a compromised exchanger can leak flue gases into your living space, replacement should never be delayed.

Why OEM matters: The Lennox 19A74 matches the exact stainless alloy, geometry, and mounting specifications of your original part. Aftermarket units frequently use thinner or inferior steel that warps and cracks under repeated heating cycles, jeopardizing safety and voiding your warranty. Installing the factory-correct OEM assembly ensures a precise fit, maximum efficiency, and long-term reliable heating.

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 Stainless Steel Heat Exchanger — 19A74?
Yes. This is the factory-specified OEM heat exchanger for the Lennox OEM Lennox Stainless Steel Heat Exchanger — 19A74. 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 Stainless Steel Heat Exchanger — 19A74?
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.
Home Shop Search Account Cart
Fitment Guaranteed
MR
Mike Rivera
HVAC Parts Specialist — Online