Duct smoke detectors and sampling tubes
A duct smoke detector watches the air moving through an HVAC system and shuts the unit down before it distributes smoke through the building. It is not a substitute for area smoke detection, and it is usually installed to satisfy the mechanical code on air handlers above a given capacity, which is why these are ordered as often by mechanical contractors as by fire alarm contractors.
This line covers conventional two-wire and four-wire photoelectric duct detectors, sensor-only versions, intelligent duct detector housings in relay and non-relay versions, watertight and outdoor enclosure versions for rooftop units, duct sampling tubes across the full length range, exhaust tubes, duct coil accessories, remote test stations including versions with key operation and an add-on strobe, and replacement covers.
Choose the housing first, then the tube. The inlet sampling tube has to span the full width of the duct, so the tube length follows the duct dimension, and the tube must be oriented so the sampling holes face into the airflow. Confirm whether the housing ships with a detector head or needs one ordered separately, whether the job needs onboard relays for fan shutdown or the panel handles it, and whether the unit sits indoors, in a wet location or outdoors. Air velocity ranges and listing details are on each product page.
FSG - Fire Services Group
