The Fixed Duct Limit Thermostat Controls 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 SPST switch and opens a circuit. A manual reset button reactivates the temperature limit after the high-temperature condition has cleared. 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.

Our standard fixed temperature limit switch is available with a 5″ insertion element. Opens at 200°F.

The enclosure has an ambient temperature of -40°F to 190°F. And the element’s ambient temperature is 350°F.

Senasys takes pride in quality control and reliable operation of our components. Every switch is individually 100% tested before it leaves the plant.