The CEMCO TC Series Firestat is a push-button manual reset limit control designed for prevention of fire in warm air ducts. It may be used with gas, oil or electric forced warm air heating systems.
One or more firestats should be installed in duct work at critical temperature locations such as downstream from electric heaters, points where duct work is in close proximity to flammable materials, etc.
Firestats may be used in low voltage or line voltage circuits and are usually wired to open circuit to both heat source and blower when duct air temperature exceeds the temperature setting. If more than one firestat is connected to controls a single heat source, the firestats must be connected in series.
For a common wiring diagram, view the installation guide below.
Duct Limit Controls
These firestat duct limit switches are installed in air ducts to shut down heating, air conditioning and ventilation equipment when air temperature exceeds a pre-set limit.
The Duct High Temperature Switches feature a helix bimetal element that senses rapid increases in duct temperature, such as those caused by fire. The high temperature limit then operates an SPST switch that opens with a rise in temperature. A manual reset button reactivates the temperature limit after the high-temperature condition has cleared. These duct high temperature limits are indispensable in specialized HVAC applications and Building Automation Systems.