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HomeRepair HelpGibson Refrigerator RepairGibson Refrigerator has frost or moisture buildup around the door Repair
Gibson Refrigerator has frost or moisture buildup around the door
If you have frost or moisture building up around the mullion flap between the doors, the most common culprit is a failed mullion heater that no longer heats intermittently to melt condensed moisture. Start by testing the mullion heater for continuity with a multimeter and replace it if it reads open. Next check the door support and door guide for damage or misalignment that prevents the flap from forming a tight seal, and inspect the door gasket for twists, gaps, or tears that let warm, humid air in. Sometimes the cause is simply a door left ajar for several hours, which will clear after a proper defrost cycle once the door is kept closed. Because poor seals can lead to a fridge door not sealing or refrigerator door not closing properly, fixing the heater or replacing worn supports, guides, or gaskets will usually stop the frost and moisture. Enter your model number on RepairClinic.com to find the exact replacement mullion heater, door support, door guide, or gasket that fits your refrigerator.
01 - Gibson 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 - Gibson 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 - Gibson 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 - Gibson 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 working but fridge not cooling — could a faulty mullion heater or door gasket cause frost around the door?
Refrigerator not cooling — how do I test the mullion heater?
Refrigerator door not closing properly — which parts should I check for frost or moisture buildup?
How do I find and buy the right replacement part on RepairClinic.com?
Refrigerator not defrosting — I left the door open and now there's frost, will it clear up or do I need to replace parts?
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