Mystery Device (Solved?)

I am looking for community help identify this device. It seems to run for about 30 seconds, generally in the evening, only week days, and I am at a bit of a loss.

Any suggestions?

The closest thing I have to that is a fridge defroster. It’s certainly an unusual device, whatever it is.

I can’t remember that I’ve seen anything with that pattern in my house, with the squared off double peak like that. I suspect that NJHaley may be right in that’s a component, not a total device. it’s going to be hard to catch if it only runs for 30 seconds.

do you have the alarm on so you can look around when it fires?

Something that might be running in the evening on weekdays: maybe furnace related?

I think @NJHaley might be on the right track with a defroster component, but I would have assumed that would be more than 175 watts. I don’t know that it would be furnace related because I have hydronic heat which definitely runs in mornings and weekends, and for much longer than 30 seconds.

I have notifications set, but by the time it kicks on, gets detected, and the notification comes through, it’s too late to go looking. I’ll try the fridge next time.


I think I figured it out. I believe it is something to do with my wife’s Chevy Volt. It only shows up in the evenings after she is home, but when the car is programmed to not draw a charge because of our time of use rates.

That would explain why it doesn’t show up on weekends: low rates, so immediate charge, and with the cold weather, it is finishing charging late in the morning, not long before she leaves for work.