After a few months of running a keg refrigerator at temperatures near freezing you might notice some ice building up on the refrigeration plates and coils inside. This is a very common kegerator problem that should be addressed before too much ice forms and cracks the plastic or other parts within the keg refrigerator.
You should defrost a keg refrigerator at least once every 6 months. However, if you notice much ice build-up in your keg refrigerator, you may need to defrost more often. You will know when to perform the defrosting process when ice accumulates in your keg refrigerator and you cannot fit your beer kegs in or, when the keg refrigerator's functionality seems impaired.
When preparing your keg refrigerator for defrosting, give yourself 5-8 hours to dedicate to the project. To begin the defrosting process, remove the beer keg from the keg refrigerator. Next, unplug the keg refrigerator and remove the CO2, regulator and beer lines. This is also a good opportunity to clean your beer lines, and set them aside. Note that it is not necessary to unplug the keg refrigerator if you are able to turn the temperature down to zero degrees or the off position. Open the keg refrigerator door and leave it open. This allows the flow of warm air to enter into the kegerator and helps the defrosting process. While the door is open, lay a towel on the bottom surface to catch the water as the ice starts to melt. Now you will need to wait approximately 1-2 hours for the ice to melt inside the keg refrigerator.
As the ice melts, use the towel to absorb the melting water. You will notice that larger ice chunks will separate from the refrigeration plates and coils. Remove these ice chunks by hand as they separate away from the plates ands coils. Place a bowl or bucket under the drip tray usually located on the back side of the keg refrigerator above the compressor. The bowl will catch any spillover from the keg refrigerator's drip tray.
Once all the ice has been removed from the keg refrigerator, the cleaning process begins. When the kegerator has been washed inside, dry the appliance with clean, cloth or paper towels and let it remain open for 30 minutes to 1 hour. Continuing to dry the keg refrigerator in this way ensures that all water is removed and that excessive condensation will not occur once the keg refrigerator is re-started.
After an hour has passed, place the CO2 tanks, regulator and beer lines that were removed, back into the kegerator. Next, return your beer keg, re-set the temperature to its previous setting, and close the doors. Your keg refrigerator is now defrosted and properly cleaned.
To prevent (or at least minimize) the build up of ice inside your kegerator you can use a Kegerator Dehumidifier. It reduces condensation and moisture buildup on cooling coils and panels.