OEM Lennox C3 Controller Board — 10X87
OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
The genuine OEM Lennox 10X87 (103976-01) is a C3 controller that serves as the electronic brain for its Lennox application, coordinating inputs from sensors and thermostats and driving the outputs that run the system. It manages operating sequences, safety logic, and onboard diagnostics to keep the equipment running efficiently and safely.
Common failure symptoms: the system fails to start or respond to a call, intermittent or no communication with the thermostat or other boards, fault and error codes with no mechanical cause, blank or frozen diagnostics, and components that won't energize. Power surges, moisture, and heat are frequent causes of controller failure.
Why OEM matters: Lennox systems rely on the specific firmware, connector layout, and control logic of the factory C3 board. The correct 10X87 guarantees compatible communication, proper sequencing, and full diagnostic support — a substitute board can misfire outputs or fail to communicate on the Lennox network. Verify part 103976-01 matches your specific Lennox model and revision before installing.
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