ST Motion Sensor False Alarms

I have a new ST Hub v2 and the bundled items.

I have the motion sensor on a fireplace in the basement, facing a long room with 2 vents on the ceiling. One vent is about 4 feet from the sensor (and 4 feet lower), the other vent is 20 feet away.

It has been down there for a week and has worked like a charm. No false readings at all and detected us everytime we go down there.

Last night at 12:46am it sent me a notification and several more throughout the night. I checked downstairs and there was nothing going on. I have a dog but he sleeps in our room on the top floor. It is overcast here all day and night, so no light changes either.

This morning I moved the sensor slightly to point away from vents and it seemed to help, as it only triggered one false.

Battery is still showing 100%, so why after a week is the device triggering false movement when it never had one previously? It is freaking the crap out of my wife but I cant really pinpoint the problem. I only have this sensor, otherwise I would try and put two next to each other to see if they report the same thing.


search for previous posts on this symptom, it seems more common to me in the past 6 months.

Though forum search may make them difficult to relate.

Hi Eric,

I did a lengthy search at 1am this morning as I was wide awake in bed with adrenaline pumping! :smile:

This is the summary of what I have read in those posts:

  • Keep the sensors away from windows where light may affect motion
  • Keep them away from furnance vents as an in rush of hot air in winter may cause sensing
  • Try to set up multiple sensors in one area to see if they all trigger
  • Pull battery and replug to “reset” sensor and maybe that fixes it
  • Contact support at samsung if it continues

Thats great advice, but when my sensor is facing the wall, it appears to be fine, no faulty sensing. There must be some condition in my basement that is causing this to happen.

no, not necessarily. Your summary info is correct but ALSO several unrelated reports have indicate false motions on Multiple sensors, in close timeframe.

I’ve had 2 incidents that reported 2-3sensors with false motions in the past 3 months, in sheltered locations (no heating ducts, curtains drawn in a dark room, in unoccupied house). Cameras and other systems confirm there was no actual motion in that timeframe.

Insects/spiders can cause falsing (I had 2 incidents of that 5-6 years ago) but not on multiple sensors in close timeframe.

I don’t believe in ghosts so I assume most likley it was from ST cloud testing or ST network problems - like extremely high latency/old reports of motion.

Just don’t overreact if you get a motion alarm. You have to confirm it by another channel first.

Just don’t overreact if you get a motion alarm.

Easier said than done! :slight_smile: But youre right…

I think I may have found part of the issue yesterday evening.

I had “Notify me when” app installed on the motion Sensor and I accidentally set up notification when my phone arrived at my house WITH that app ON the motion sensor. Kind of weird it would even let me do that, but basically my phone triggered the motion sensor to “activate” itself. I can only conclude taht during the night, my phone lost GPS or something and regained it, so my ST hub thought I had left and came back, triggering an alarm.

I still got one false reading yesterday after I disabled it, but none today.

Is there an app that will let me set my alarm parameters to require 2 motion sensors to be tripped before the alarm is triggered? My IRIS system finally made this available and I never had any false alarms after that.