OEM Lennox Furnace Limit Switch — 69W40
OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
The genuine OEM Lennox 69W40 limit switch is a high-temperature safety control that protects your Lennox furnace from overheating. Installed on the heat exchanger or supply plenum, it senses air temperature and interrupts power to the gas valve or heating elements the moment temperatures exceed the safe threshold, keeping your system operating within its designed limits.
Common failure symptoms: A failing 69W40 often causes the furnace to short cycle, the blower to run non-stop, or the burners to fail to ignite at all. You may also see the control board flash a limit-open or high-limit fault code. These issues typically point to a switch that has drifted out of calibration or opened permanently.
Why OEM matters: Limit switches are calibrated to precise cut-out and cut-in temperatures matched to your specific Lennox model. An OEM 69W40 ensures the exact trip point, mounting footprint, and terminal configuration the factory intended — avoiding the nuisance trips and safety compromises that come with mismatched aftermarket parts.
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