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HomeRepair HelpU-Line Refrigerator RepairU-Line Refrigerator has frost or moisture buildup around the door Repair
U-Line Refrigerator has frost or moisture buildup around the door
Frost or moisture buildup around the refrigerator door usually points to a sealing or mullion-heater problem rather than a cooling failure. The most likely cause is a failing mullion heater flap that should heat periodically to melt condensation; test the mullion heater with a multimeter for electrical continuity and replace it if it has no continuity. If the heater checks out, inspect the door support and door guide next — wear or misalignment can keep the mullion flap from forming a tight seal and allow humid air in. A damaged, twisted or torn door gasket is the next likely culprit because gaps let warm air enter and can leave the freezer cold while the fridge warms. Finally, confirm the door was not left open for hours, which can cause temporary frost that clears after a defrost cycle. Enter your model number on RepairClinic.com to find the exact replacement mullion heater, door support, door guide or gasket for your refrigerator.
01 - U-Line Refrigerator Mullion Heater
A defective mullion heater flap may not be able to heat up periodically to melt any frost or moisture that forms on the flap due to increases in room humidity. You can use a multimeter to test the mullion heater for electrical continuity to determine if the component is working. If the mullion heater has no electrical continuity you should replace it with a new one.
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Common
02 - U-Line Refrigerator Door Support
If the mullion heater flap has frost or moisture buildup, it's possible the door suport is damaged or misaligned and not allowing the flap to form a tight seal between the refrigerator doors. Inspect the door support for wear or damage and replace if necessary.
Common
03 - U-Line Refrigerator Door Guide
If the mullion heater flap has frost or moisture buildup, it's possible the door guide is damaged or misaligned and not allowing the flap to form a tight seal between the refrigerator doors. Inspect the door guide for wear or damage and replace if necessary.
Common
04 - U-Line Refrigerator Door Gasket
A door gasket should form an airtight seal around the appliance's frame to keep the cold air in and the warm air out. If the door gasket is twisted or torn, gaps can form that will allow warm air in, resulting in the freezer not freezing properly. Inspect the door gasket for any damage and replace with a new one if necessary.
Common
05 - Refrigerator or freezer door left open
If the freezer or refrigerator door was left open for an extended period of time (more than 4 hours), frost may have accumulated on the food and around the door opening. The frost should go away after the door is closed and the refrigerator goes through a defrost cycle.
Common
Frequently Asked Questions
Why is there frost or moisture buildup around my refrigerator door?
My freezer is cold but the refrigerator is warm — can frost on the mullion cause that?
How do I test the mullion heater to see if it needs replacing?
How can I tell if I need a door gasket, door support, or door guide?
How do I enter my model number to find the correct replacement part on RepairClinic.com?
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