Mars L240-4 Limit Switch, Open on Temp Rise at 240, Auto Close at 200 (39028)

About the Mars L240-4 Limit Switch, Open on Temp Rise at 240, Auto Close at 200 (39028)

Enjoy this deal on the Mars 39028 240 Limit Switch L240-40 Auto Reset 3/4" while supplies last at PlumbersStock. Limit switches are sensors that detect when a furnace has exceeded operational temperature limits and shut the appliance down as a safety measure. The way it works is that if your temperature gets to a concerning level, the limit switch will automatically open the circuit so it shuts off. It will remain off until the switch automatically closes the circuit when the temperature reaches the off threshold. Mars makes reliable HVAC products that will get the job done.