System Sensor 5621 135°F Fixed Temp/Rate-of-Rise, Dual-Circuit Mechanical Heat Detector

Built to deliver dependable fire detection for commercial and non-life-safety installations, the System Sensor 5621 dual-circuit mechanical heat detector offers practical, low-cost protection for property and security assets. This heat detector combines a 135°F fixed-temperature element with a rate-of-rise (ROR) trip for faster response to rapidly developing fires, while the ROR element is restorable to simplify field testing and reduce maintenance-related downtime. Designed for wired integration into alarm systems and security monitoring setups, the 5621 mounts easily to single-gang, octagonal, or 4" square back boxes and features clear exterior markings and user-friendly terminal screws to speed installation and commissioning. Ideal for equipment rooms, utility closets, garages, and other spaces where smoke detection is not suitable, the 5621 provides reliable detection that works seamlessly with surveillance and building monitoring systems. Specify the System Sensor 5621 for dependable heat detection in your next security, fire detection, or alarm system project — contact your supplier to order or request a quote.

• Provides reliable property protection with a dual-circuit mechanical design and 135°F fixed-temp plus rate-of-rise (ROR) activation
• Reduces service time and false trips with a restorable ROR element for straightforward field testing and maintenance
• Cost-effective solution for non-life-safety commercial areas where smoke detectors are inappropriate, supporting security and alarm system integration
• Simple wired connectivity and versatile mounting to single-gang, octagonal, or 4" square back boxes for faster installation and retrofit projects
• Clear exterior markings and easy-to-use terminal screws streamline commissioning and ongoing monitoring