Building, fire and life safety codes often require the installation of duct smoke detection in heating, ventilating, and air conditioning (HVAC) ducts for the detection of fires in an HVAC System. Typically, these codes refer to NFPA 90A, Standard for the Installation of Air Conditioning and Ventilating Systems, to determine if and where they are required.
Duct smoke detectors provide early detection of smoke and products of combustion present in air moving through HVAC ducts. These devices are designed for prevention of smoke recirculation in areas by the air handling systems. Fans, blowers and complete systems may be shut down in the event of smoke detection.
Duct detectors typically offer universal voltage input compatibility (i.e. 24VDC, 120VAC, etc). Air sampling on a duct detector is typically accomplished by an intake sampling tube which protrudes into the duct.
Accessories for duct detectors can include remote test /rest stations to test duct smoke detectors from a convenient location and a piezo annunciator to provide an audible alarm signal without the use of a system control panel.