I had my motion sensor trigger an alarm this morning shortly after we left the house, We have no pets. We have a fireplace, but it is not on.
Has this motion detector false alarmed before? Where is it located in relation to the heating vents? Any cobwebs covering it?
I would suspect thermal…leave blinds/curtains open? Heating registers/vents…
If near registers, vents, or it sees a window/glass door, or even the sunlight on the floor, and that light shifts or changes at all (clouds, sunrise, sunset), it’ll cause the thermal “snapshot” of the passive infared lense to change…thus activating.
This is usually the culprit for my PIR when it falses (sunlight, as it partially sees a window/sunlight on floor if I fail to close a bedroom door)
Now that its getting cold, and everyone is cranking up heat, or setting tstats for automatic heat, I suspect there will be a lot of PIR’s (motion detectors and Image sensors) falsing (especially on recent installs, where they may not have taken into account that the PIR may be seeing the thermal heat from registers/vents)