Lennox 71J07 Limit Switch you must ensure the control

you must ensure the control circuit provides a stable 24V DC signal to avoid chatter or failure

Designed with high-conductivity silver alloy contacts

it offers a reliable digital upgrade for older mechanical mercury-bulb thermostats

furnace short cycling or a 6-flash error code on the integrated furnace control (IFC) often points directly to a fouled or failing HVAC flame probe

Always verify output voltage at the connector before installing to prevent immediate burnout

Lennox 71J07 Limit Switch you must ensure the controlThe Lennox 71J07 Limit Switch is a high precision, normally closed safety component designed for critical temperature regulation in heating systems. Engineered by Therm O Disc (Model 36TX11, 36T series), this disc style limit switch features an automatic reset function that ensures seamless system recovery once temperatures stabilize. With an open temperature threshold of 175F and a close temperature of 155F, this L175 20 limit switch effectively