White Kenmore 564.98291890 - Freezing in...

Question

I have a white Kenmore 564.98291890 compact frig. It has two doors: freezer on top and frig on the bottom. It's about five years old and it's been acting up in the last two months. The bottom frig is starting to freeze food and drinks. So I've been turning it off the dial and let it unfreeze for a few hours. I've also check if the unit is leveled and gave the back a few inches of space. I tapped the motor in the back and brought the dial to 0, then to 3 when I plugged it back in. For awhile everything works for two to three days. After that it starts to freeze everything. Is it something in the back or the computer board? Or is it because its on a thin carpet in my room?