System Sensor DNR Intelligent Photoelectric Duct Detector System Sensor DNR intelligent non-relay photoelectric duct smoke detectors and DNRW water-tight non-relay photoelectric duct smoke detectors feature a pivoting housing that fit both square and rectangular footprints capable of mounting to a round or rectangular duct. These units sense smoke in the most challenging conditions, operating in airflow speeds of 100 to 4,000 ft/min (0.5 to 20.32 m/s. FAQ What is the System Sensor DNR duct detector used for? It is used to monitor air currents in heating, ventilation, and air conditioning (HVAC) systems to detect smoke and toxic gases, signaling the fire alarm panel to shut down fans and blowers to prevent smoke circulation throughout a facility. What types of HVAC ducts is the System Sensor DNR compatible with? It is compatible with both round and rectangular ducts using a flexible pivoting housing that accommodates both square and rectangular footprint mountings. How does the System Sensor DNR detect smoke in HVAC systems? It uses sampling tubes extending into the air duct to continuously draw air samples through the housing across an internal photoelectric sensor, capable of operating in airflows from 100 to 4,000 feet per minute. Does the System Sensor DNR require a separate detector head? Yes, the DNR is an intelligent non-relay housing and requires a compatible plug-in photoelectric smoke detector head (such as a System Sensor addressable sensor) to function. What is the difference between the System Sensor DNR and DNRW models? The DNR is designed for standard indoor applications, whereas the DNRW features a NEMA 4-rated watertight and UV-resistant housing suitable for outdoor or harsh environments. How is the System Sensor DNR duct detector installed? It mounts directly onto the exterior of the ductwork with a tool-free sampling tube installed through the duct, and its modular housing pivots to adjust to either square or rectangular mounting templates.
