I see that quite a bit in vacant homes. Everyone gets tired of hearing that “beeping” sound!
I was testing smoke alarms in a 3 bedroom. 1 in each bedroom, 1 in the hall, 1 outside the master bedroom on living room ceiling…then chirp…chirp…chirp, after 20 minutes pulling my hair out I am standing in the kitchen and this is what I finally see…a spare with an old battery. lady said she wondered what chirping noise was!
So that’s where all those missing smoke detectors from my last inspection are!
Must be expecting a fire in the fridge ! :D:D:D