A vintage home security job has me puzzled by false triggers

I set up a full alarm system in a house from the 1920s a few days ago. Now the motion detectors go off randomly, often at night when the place is empty. I rechecked all the sensors and wiring, and it all looks correct. Even tried adjusting the sensitivity, but no luck. Maybe it's the old floorboards settling or drafts from original windows. Has anyone else run into this with older buildings? What did you do to make it stop?

3 comments

3 Comments

eric1821mo ago

It might not be drafts, but temperature swings. Those old houses can have wild temperature changes in different rooms. Are your motion detectors the passive infrared type, and are any of them aimed right at a heat register or an outside wall that gets cold at night?

nancy_nelson271mo ago

Have you checked if any detectors point at vents or windows? My friend's old place had false alarms from a sensor near a drafty door. Those PIR types pick up heat changes, so cold walls at night can set them off. Maybe move them to inside walls away from temperature swings? Would adding a second sensor type help avoid this?

laura2111mo ago

Could it be that the house itself is moving more than you think? I swear, every old building has its own vibe that messes with electronics, lol.