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

Menu

Home Shop All Account Cart
OEM Lennox Limit Switch — 79J63
Lennox

OEM Lennox Limit Switch — 79J63

SKU: LNX-79J63 Brand: Lennox
$19.95 $28.95

OEM Guaranteed

Same-Day Ship

30-Day Returns

Secure Checkout

Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

The genuine OEM Lennox 79J63 limit switch is a critical safety control that monitors the temperature inside your furnace's heat exchanger. If the unit overheats — typically due to restricted airflow or blower issues — this switch opens the circuit to shut off the burners, protecting the heat exchanger from cracking and preventing a potential fire hazard.

Symptoms of a faulty limit switch include the furnace short cycling, the blower running non-stop, no heat output, or the system tripping into lockout. A switch that opens prematurely or fails closed can leave your Lennox furnace either inoperable or unsafe.

OEM matters here more than anywhere: the 79J63 is calibrated to the exact trip and reset temperatures specified for your Lennox model. A generic switch with the wrong temperature rating can allow dangerous overheating or cause constant nuisance shutdowns. Install the factory part for correct, code-compliant protection.

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 Limit Switch fit my Lennox OEM Lennox Limit Switch — 79J63?
Yes. This is the factory-specified OEM limit switch for the Lennox OEM Lennox Limit Switch — 79J63. 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 limit switch on my Lennox OEM Lennox Limit Switch — 79J63?
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 limit switch?
Common symptoms: unusual noises, intermittent operation, complete failure, or visible damage. Visit our diagnostic hub for symptom-based troubleshooting.
Is this limit switch 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 limit switch?
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