testingFirestat duct high limit units are designed to accurately read the temperature inside your duct system, and in the case of a fire it reads the high temperature and shuts off the fan system, so that the potential fire causing the high temperature in the duct does not spread. Our Firestat’s are tested before they get sent out the door to our customers, but testing your firestat them at your home as a precaution is recommended, or you may need to test them if you think it may not be functioning accurately.

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Testing your firestat is simple! Wire your Firestat to a fan system, set your temperature, and increase the heat around it to reach higher than the system is set at. Once the air temperature around the probe exceeds the units’ set temperature, it should shut the fan off. You will have to pull back on the manual switch to reset the unit once complete. If the unit functions correctly it’s ready to be installed. If the unit does not properly function for any reason, make sure to give us a call to diagnose the problem.

Always make sure to test your Firestat’s function ability prior to installation. Contact us if your Firestat does not function properly for any reason.

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CEMCO Duct Limit Switches

The Firestat Duct Fan and Limit Thermostat Switches operate using the same physics to ensure HVAC safety. A helix bi-metal element senses a rapid temperature change. When the temperature changes the bi-metal expands and triggers a snap action switch and either opens or closes a circuit. These switches are commonly installed in air ducts designed to shut down heating, air conditioning and ventilation equipment in apartment complexes and other multiple dwelling units when air temperature exceeds the set point.

UL & cUL Approved
Made in the U.S.A.