It was beeping constantly, like a smoke alarm. Like someone was pushing the buttons but the door was closed, and we had no known poltergeist activity for a few years. It kept getting worse and worse till we had to unplug it at night so we could sleep. Troubleshooting online was useless, but the paper manual actually had the answer in it. I overnighted the part and it was six days from when the problem started to win it arrived. The FedEx guy wasn’t even at the end of our road before I had it swapped out and it’s finally quiet.