My problem was that I moved the unit from an outside location to inside the house. I noticed the room was abnormally warm and didn't notice the unit shutting off. It wasn't defrosting either. I knew it had to be a simple fix. I read some comments to help diagnose my problem. Replace the timer and it is good to go! 2 screws and a wired connector. $45 counting shipping is a great price. Part arrived in 3 days.