Model #FFU21M7HWA, the complaint was ice began building up on the surface of the liner and the door at the top of this freezer located in the garage. Each time the customer would get into the freezer, she noticed the mound of ice seemed to be getting larger and was beginning to run back along the top of the liner toward the rear of the unit. Whenever I have a call for ice buildup inside any type of refrigeration unit, I usually have one question of the customer. Does it feel like snow? Because if if it has the consistency of snow, it's time to go looking for an air leak.
A Little Theory
Refrigerators and freezers cool by removing heat from inside the cavity and moving it to a place that is less objectionable, usually under or behind the cabinet. In order to cool efficiently, the refrigerator doors have flexible door gaskets that allow for an air tight seal when the door is closed. These gaskets contain a permanent magnet running their entire length that pulls and holds the door closed maintaining the air tight seal. If for some reason the seal is not made in a particular section of the gasket, the result will be frost forming on the surface of the cooler interior liner as warm moist air condenses and then freezes.
Looking for Leaks
The repair for this type of failure is usually as simple as locating the air leak, and repairing the gasket. If you see frost forming anywhere on a refrigerators liner, an air leak should be very near by. On this particular unit, the gasket at the very top of the freezer door was not sealing, allowing air to easily enter the cavity and freeze. And because we have had temperatures in the high 90's along with very high humidity for the area this week, there was plenty of moisture in the air to make frost. With the door slightly open, and using a hair dryer to apply some heat to the door seal, I waited until the gasket become flexible and slowly closed the door until the magnet pulled itself toward the door frame and sealed tightly. This may require a bit of patients as you apply slow even heating. If the seal is torn, pealing, or in anyway no longer in one piece, it will need to be replaced with a new door gasket , and then you can use the hair dryer to get the new one to form and seal properly.