Frost builds up on freezer walls. I have lubricated the gasket and defrosted the freezer.

The refrigerator is supposed 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. Poor cooling is often the result of a heavy frost build-up on the evaporator coils. You can't see these coils without removing a panel on the inside of your freezer. 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. Such a frost build-up usually indicates a problem in the self-defrosting system or damaged door gaskets.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. (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 (also called the bi-metal switch) The defrost heater. To determine if the defrost heater is burned out, watch this part testing video

The refrigerator is supposed 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. (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: Poor cooling is often the result of a heavy frost build-up on the evaporator coils. You can't see these coils without removing a panel on the inside of your freezer. 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. Such a frost build-up usually indicates a problem in the self-defrosting system or damaged door gaskets. The defrost timer The defrost thermostat (also called the bi-metal switch)

what the problem most likely is a failed part of the defrost system Do you see a bunch of frost built up on the back wall of the freezer? If you do frost build up, take off the back wall of the freezer and replace the defrost heater and defrost thermostat. A hair dryer could be used to melt the built up frost from the coil behind the back wall. Another part that will cause frost build up is the defrost control, that isn't the freezer behind the back wall but instead it is part of the main computer board on the back of the refrig. I would replace heater/defrost thermostat first though, since they are the most likely to fail parts.

I hope my answer will help you to fix your refrigerator,
Gene

Hello Roxanne,

what the problem most likely is a failed part of the defrost system Do you see a bunch of frost built up on the back wall of the freezer? If you do frost build up,i would take off the back wall of the freezer and replace the deforst heater and defrost termination. A hair dryer could be used to melt the built up frost from the coil behind the back wall. Another part that will cause frost build up is the defrost control, that isn't the freezer behind the back wall but instead in the fresh food compartment in the control panel where the thermostat is. I would replace heater/defrost termination first though since they are the most likely to fail parts.

I hope my answer will help you to fix your refrigerator,
Gene

The first thing you should be looking for is a frost or "snowy" build up on the back wall of the freezer. Assuming that there is a build up then you need to remove the back wall of the freezer. Gaining access to the defrost thermostat and defrost heater is a little difficult due to the frost build up. the defrost thermostat is attached to the evaporator coils to the right of the fan assembly. You need to check for continuity across the thermostat. The thermostat is the most likely cause.

1)The door gasket on the freezer door helps keep the cold air in and the warm air out. If the gasket is dirty or damaged, it may prevent the door from closing properly, which can lead to frost buildup on your freezer walls. To make sure the door is sealing, slip a dollar bill or a sheet of paper between the gasket and the freezer and then close the door. If the bill or paper pulls free with little or no resistance, the gasket isn't sealing properly. Wipe the gasket with a damp cloth to remove dirt, grease and other residue. If the gasket is damaged, replace it with a new one. Sometimes frost can accumulate on the back panel of your freezer if the door is open too long or too often. When you open the door, you let warm, humid air inside, and this condenses and freezes. Make sure there are no packages preventing the door from fully closing, and limit how often you open the door by removing what you need all at once.
2)Ventilation is important because it ensures your freezer stays cold. If something inside the freezer blocks the internal vents, the freezer may become warm, causing condensation to form on the walls, and eventually leading to frost buildup. When loading your freezer, make sure there are no items resting against the rear wall of the freezer and space the contents out as much as possible to improve ventilation.
3)Side-by-side refrigerators with a built-in ice maker may accumulate frost if the flap on the ice dispenser doesn't close properly. This allows warm air to enter the freezer side, condense and freeze, causing frost buildup over time. Open the freezer door and examine the flap inside the ice chute. It should be flush against the housing. If it is not, empty the ice bin and make sure there is no ice or debris preventing the flap from closing.
4)If your freezer door closes properly and nothing is keeping it open, frost buildup on the back panel may indicate a problem with the freezer's self-defrost system. The self-defrost system turns off the compressor for a short time every six to 12 hours so it can turn on the defrost heater. This melts any frost buildup on the freezer coils, and the water drains to the pan beneath the freezer. If this component fails, frost continues to build. Move the contents to another freezer and turn your freezer off for 24 to 48 hours to manually defrost the interior. If frost builds up again, contact a qualified appliance repair technician to inspect the defrost timer and repair the problem.

Either the door gasket is not sealing well or the unit is low in refrigerant.

if there is frost build up on rear wall of freezer section the unit is not going through defrost cycle which builds up frost on evaporator and restricts cold air flow to the fresh food section. one of three things are bad. defrost heater, defrost thermostat or defrost timer. if no frost on rear wall you might be low of freon.

It could be the door gasket. It could also be that the fridge needs a good defrosting. (especially if it is an older fridge)

When I bought my house I had the same problem with the fridge that came with the house. I assumed the previous owner had been defrosting it regularly, which he had not.

Eventually I decided to try a full defrost, and my fridge now works like new.

If the ice build up is only on the back panel of the freezer then you have a defrost problem. Most likely a defrost thermostat or control board/timer. If frost build up is around the walls of the freezer then warm air is getting into the freezer. Most likely cause of this would be gaps in or torn door gasket or door alignment. In some cases the door was left cracked open. If gasket and door alignment is ok remove the frost and see if it comes back.