Why is my refrigerator freezing up? The piece in the rear legs of the fridge that cools...

The piece in the rear legs of the fridge that cools the fridge downs inside the freezer seems to preserve freezing over and we have to hold on to thawing it out to variety it work properly again..if you know why it does this any info would be greatly appreciated
Answers:    More than likely its mortal opened & closed too frequently.If not that, check your door gasket. It may not be sitting room and sealing properly. This will motive a ref to ice out unbelievably quickly. It the gasket is a bit worn, but not completely bad, a righteous coating of vaseline works wonders. Otherwise, it'll mean a clean door gasket. Good luck.

I've had this problem a few times!
Every 8 hours or so your rime box defrost timer will shut down the sealed system for 21 minutes. The defrost electric fire comes on and gets the coils thaw out enough to de-ice any frost that may have gotten on the evaporator coils. If that boiler was to stay on the full 21 minutes afterwards the heat would spoil the ice box. So they install a defrost thermostat. Commonly call a terminator. This terminator will shut down the heater when the temp reach 50F. My best guess is your heater have failed. It is recommended you modify both parts when their is a problem. One other thing to check is your defrost timer. It's little timer motor may be burned out and not moving it around to the defrost mode.