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HomeRepair HelpLG Refrigerator RepairLG Refrigerator has frost or moisture buildup around the door Repair
LG Refrigerator has frost or moisture buildup around the door
If you see frost or moisture building up around the door mullion or between the doors, the most likely cause is a defective mullion heater flap that no longer heats enough to melt condensation. You can use a multimeter to check the mullion heater for electrical continuity; no continuity means replacement. If the heater checks out, inspect the door support and door guide next — worn or misaligned parts can prevent the flap from forming a tight seal. A twisted, torn, or compressed door gasket is another common cause because it lets warm, humid air in and can even keep the freezer from freezing properly. Sometimes the problem is simply a door left open too long; frost should clear after a defrost cycle once the door seals again. These faults often present as a refrigerator not cooling or a fridge door not closing properly or fridge door not sealing. Enter your model number on RepairClinic.com to find the exact replacement mullion heater, door support, door guide, or gasket for your refrigerator and get step-by-step repair guidance.
01 - LG 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 - LG 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 - LG 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 - LG 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
Freezer cold but fridge warm: can frost or moisture around the door cause the fridge not to cool?
How do I test an LG refrigerator mullion heater with a multimeter?
Refrigerator door not closing properly: how do I check the gasket, door support, and door guide?
I left the refrigerator door open and now there is frost around the door. Will it clear on its own?
How do I enter my model number or part number on RepairClinic.com to find the correct replacement part?
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