Mars MR240 Manual Reset Limit Switch, Open on Temp Rise 240 (39042)

About the Mars MR240 Manual Reset Limit Switch, Open on Temp Rise 240 (39042)

Save big on the Mars 39042 240 Limit Switch MR240 Manual Reset 3/4" here 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. The circuit will remain open/off until it is manually reset. Mars is known for engineering innovation and practical solutions.