Kidde-Fenwal, Inc. products

The DH-60 Series Duct Detectors are suited for use with HVAC systems in commercial, industrial and institutional fire alarm applications. The DH-60 is easily mounted to both rectangular and round ducts from 8 inches (200 mm) to 12 feet (3.6 m) wide and is compatible with all ducts with air velocities between 500 and 4000 feet per minute (2.5 to 20 m/s). The operation of the DH-60 Duct Detector is based upon an air sampling principle. Two tubes extend into the HVAC duct to transport air from inside the duct into the duct detector sensing chamber and back out to the duct. If the sampled air contains a concentration of smoke greater than or equal to the alarm threshold of the internal smoke detector, the unit will alarm. The duct detector inlet supply sampling tube is selected according to the size of the HVAC duct. A separate exhaust tube is not required since an integral tube is molded into the housing to simplify installation.