The evap keep freezing up
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You need to have access to the evaporator coil unit. This is be done by opening the walls from inner side of the freezer compartment. A sure sign that there is a build-up is the presence of any frost or ice build-up on the inside walls, floor, or ceiling of the freezer that is exactly the thing you quoted. Such a frost build-up usually shows a problem in the self-defrosting system or damaged door gaskets. This refrigerator is supposed/designed to self-defrost approximately four times in every 24 hour period. If one of the components in the self-defrosting system fails, the refrigerator continues to try to cool. Eventually, though, so much frost builds up on the evaporator coils that the circulating fan can't draw air over the coils. There may still be a small amount of cooling because the coils are icy, but with no air flow over the coils, cooling in the refrigerator compartment is quite limited. Here's an inexpensive, though inconvenient, way to determine if the problem is with the self-defrosting system. Remove all of the perishable food from the refrigerator and freezer, turn the thermostat in the refrigerator to Off, and leave the doors open for 24 to 48 hours. Check for the clogged channel/tube for water passage to the drip pan and remove the blockage/contamination if any. (Be sure to have several towels ready in case the melting frost and ice causes the drip pan to overflow). This allows the refrigerator to defrost "manually." When the frost and ice build-up has completely melted away, turn the thermostat back to a normal setting. If the refrigerator then cools properly, it indicates a problem with one of three components in the self-defrosting system:
The defrost timer
The defrost thermostat
(usually a bi-metallic switch)
The defrost heater
Also you need to clean the dust, lint from the condenser unit by using a condenser brush or a vacuum cleaner to remove all the dust from the unit (it is usually located at the back of the refrigerator). If it still does not cool properly, there may be a problem with the refrigerant level or the compressor or in severe case it might be the main CU mal-function. If the problem still persists and the above quoted techniques/tips didn't work,You may need a qualified appliance repair technician to further diagnose the problem.
Best of Luck,
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Concerned.
