Hvac Duct Smoke Detection

Why are smoke duct detectors required on the supply side as noted above.

Hvac duct smoke detection.

If the duct system is designed to carry more than 2000 cfm 5 tons nominal of air you need one in the return if imc is being followed and the supply if nfpa is being followed. The duct smoke detector is equipped with an auxiliary relay. A duct smoke detector should shut off a typical blower and fresh air and turn on the exhaust. Its purpose is to prevent the re circulation of smoke from an area on fire to areas unaffected by the fire when used with a xp95 or discovery detector.

Nfpa 72 also states that a duct smoke detector is not allowed to replace an area smoke detector mainly because if the air handling unit ahu is not running the detector would not detect smoke. Duct smoke detectors provide early detection of smoke and products of combustion present in air moving through hvac ducts. Duct smoke detection may be useful in preventing injury and property dam age in instances such as the following. Hvac duct smoke detection.

Tool free plug in sampling tubes speed and simplify installation. Duct detectors smoke detection nfpa 90a code requirements. A heating ventilating or air conditioning hvac fan motor overheats and resulting smoke is sensed by the duct smoke detector installed in the main supply duct. I ve had this question asked of me several times.

The duct smoke detector should be compatible with building automation and fire alarm systems. While i am a licensed master hvac contractor i am not a code official but here is my answer. Therefore duct smoke detectors are typically considered mechanical equipment devices instead of life safety devices. The duct smoke detector samples air for early detection of smoke and products of combustion present in air moving through hvac ducts.

This one hour webinar includes basic code and testing requirements the different types of duct smoke detectors and how they operate installation and placem. The damper is still protected with the in duct smoke detector to ensure the rating of the wall to shut the damper upon detection of smoke and if the in duct smoke detector activates then we go through the shut down process of the fans and dampers throughout the building as exampled above. One unit can accommodate multiple installation footprints to overcome mounting constraints. 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. Innovairflex duct smoke detectors combine an impressive collection of innovations to greatly simplify hvac system monitoring.