Lennox 20J83 Limit Switch This model features a 304

This model features a 304 stainless steel 50 mesh screen

maintaining the electrical integrity of the system without the "marketing fluff" of lower-tier universal components

What symptom indicates a failed damper door spring

As a critical replacement part

This assembly ensures precise gas flow control and stable pilot flame maintenance

Lennox 20J83 Limit Switch This model features a 304The Lennox 20J83 Limit Switch (Model 20J8301) is an essential HVAC OEM replacement part engineered for precise thermal management in high efficiency furnaces. This single pole, single throw (SPST) automatic control is factory calibrated to actuate at 165F, effectively breaking the circuit to prevent heat exchanger damage or unsafe operating conditions. Once the plenum temperature cools to 135F, the switch automatically resets, restoring normal system