Smoke Detector.

[ARTICHILL]

regradless of mua, open return or ducted return if a fire breaks out anywhere in or around the building you need to shut down units and close all fire/smoke dampers god forbid anything like that should happen we as HVAC techs can make a huge impact to human safty not to mention building lol

[Elfshadow]

regradless of mua, open return or ducted return if a fire breaks out anywhere in or around the building you need to shut down units and close all fire/smoke dampers god forbid anything like that should happen we as HVAC techs can make a huge impact to human safty not to mention building lol

I know this, its why our units have contacts for a remote smoke detector in them.