If you check them and need to replace, make sure you also check out System Sensor's flexible options.
HVAC Duct Smoke Detection
InnovairFlex™ duct smoke detectors combine an impressive collection of innovations to greatly simplify HVAC system monitoring. One unit can accommodate multiple installation footprints to overcome mounting constraints. Tool-free, plug-in sampling tubes speed and simplify installation. Broad temperature and humidity ranges accommodate exposure to environmental extremes. Easily visible status indications, readily accessible test feature, and a remote test station accessories simplify testing and maintenance. With its unmatched flexibility, InnovairFlex can adjust to fit any application.
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