cemco duct High limit switches
Firestat Duct High Limit Controls are designed to enhance HVAC safety by using a helix bi-metal element to detect rapid temperature increases. As temperatures rise, the bi-metal expands and activates a snap-action switch to open or close the circuit.
These high-limit controls are typically installed in air ducts to automatically shut down heating, air conditioning, or ventilation equipment when air temperature exceeds the set point. Common applications include apartment complexes and multi-dwelling units, where Firestat controls help prevent overheating and ensure safe system operation.
CERTIFICATION
Firestat Duct High Limit Controls are UL Approved and fully compliant with Section 607.3.1 of the North Carolina Mechanical Code, ensuring they meet industry standards for safety and performance.
CUSTOM OPTIONS
Firestat Duct High Limit Thermostat Switches are customizable with selectable temperature ranges, element lengths, and fixed temperature set points to meet specific HVAC application requirements.
MADE IN THE U.S.A.
Senasys temperature and limit switches are 100% tested for quality and reliability before leaving our facility, ensuring consistent performance in every application.
SAFETY
Safety is our priority. Firestat Duct High Limit Controls are an ideal solution for apartment complexes and multi-dwelling units, helping prevent hazardous conditions by monitoring and controlling overheating in HVAC air ducts.
Firestat Duct High Temperature Switches use a helix bimetal element to detect rapid rises in duct temperature, such as those caused by fire or equipment failure. When temperatures exceed the high limit, the SPST switch opens the circuit to shut down HVAC systems. A manual reset button is provided to reactivate the control once the temperature returns to a safe level.
These switches are critical components in specialized HVAC applications and Building Automation Systems, helping prevent overheating and supporting system-wide safety compliance.
Adjustable and Fixed Temperature Models
Firestat models are field adjustable within a temperature range of 100°F to 250°F and are available with 5-inch, 7.5-inch, or 11-inch bi-metal insertion elements. Custom element lengths, such as 3-inch, are also available upon request.
The TC-205 Duct High Temperature Limit Switch is a fixed-temperature model featuring a 5-inch element, offering consistent performance for standard applications.
Durability in Demanding Conditions
The Firestat enclosure operates in ambient temperatures from -40°F to 190°F, while the sensing element can withstand temperatures up to 350°F, making these controls reliable in a wide range of duct system environments.
ADJUSTABLE DUCT LIMIT CONTROL SWITCH
TC Duct Limit Controls utilize a helix bi-metal element to detect rapid temperature increases in duct systems, such as those caused by fire or airflow disruptions. As temperatures rise, the bi-metal expands, triggering the normally closed contacts to open and disconnect power to the HVAC system.
Adjustable models are available with 5-inch, 7.5-inch, or 11-inch insertion elements, allowing flexibility for various duct configurations and system requirements.
PRODUCT SPECIFICATIONS
Setpoint Temperature Range: 100°F to 250°F
Reset: Manual Reset
Voltage: 120-240 VAC
Amp Rating: 4.9 FLA @ 240 VAC / 9.8 FLA @ 120 VAC / 29.4 LRA @ 240 VAC / 58.8 LRA @ 240 VAC
Temperature Sensor: Helix Bi-Metal
PURCHASE
View product to purchase online, or contact us for quantity based pricing.
FIXED DUCT LIMIT CONTROL SWITCH
TC Duct Limit Controls use a helix bi-metal element to sense rapid increases in duct air temperature, such as those caused by fire or system malfunctions. As the temperature rises, the bi-metal expands, forcing the normally closed contacts to open and disconnect power to the HVAC system.
Our standard fixed temperature limit switch is available with a 5-inch insertion element, providing dependable protection for a wide range of duct applications.
PRODUCT SPECIFICATIONS
Fixed Temperature Setpoints: 125°F, 165°F or 200°F
Reset: Manual Reset
Voltage: 120-240 VAC
Amp Rating: 4.9 FLA @ 240 VAC / 9.8 FLA @ 120 VAC / 29.4 LRA @ 240 VAC / 58.8 LRA @ 240 VAC
Temperature Sensor: Helix Bi-Metal
PURCHASE
View product to purchase online, or contact us for quantity based pricing.
Other custom temperature & element length options are available, please contact us.
DUCT FAN & LIMIT SWITCH
Senasys is actively researching new options to expand the capabilities of our TC Series Duct Limit Controls. While our current models are designed to open on temperature rise, we are exploring additional configurations, including close-on-temperature-rise and SPDT switch options, which would allow the control to open and close two sets of contacts in response to rising duct temperatures.
As product development progresses, we will keep our customers informed and announce availability once the new models are finalized.
Stay informed by submitting your email to receive updates.