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HomeRepair HelpRefrigerator RepairRefrigerator has frost or moisture buildup around the door Repair
Refrigerator has frost or moisture buildup around the door
Frost or moisture around the refrigerator door usually means warm, humid air is getting past the mullion heater flap or the door seal and condensing on cold surfaces. The most likely cause is a faulty mullion heater flap that isn’t heating to melt condensation—test it with a multimeter for continuity and replace if it’s open. If the heater is fine, check the door support and door guide for wear or misalignment that prevents the flap from seating properly. A twisted, torn, or compressed door gasket can also allow warm air in, so inspect and replace any damaged gasket. Finally, rule out the simple stuff: a freezer or fridge door left open for hours will build frost until the unit completes a defrost cycle. This is a common reason for a refrigerator door not closing or a fridge door not sealing. If you need parts, enter your exact model number on RepairClinic.com to find the correct replacement mullion heater, door support, guide, or gasket for your refrigerator.
01 - 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 - 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 - 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 - 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 my refrigerator not cooling and I have frost or moisture buildup around the door?
My fridge not cooling but freezer works: can frost around the door cause that?
How do I test the refrigerator mullion heater when I see frost on the mullion?
Refrigerator door not closing properly: how do I know if I need a new door gasket, door guide, or door support?
How do I enter my model number or part number on RepairClinic.com to find the correct replacement part?
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