A sticking freezer door is not usually caused by a faulty or damaged gasket. Often when the gasket is damaged, your door won't seal at all. Your freezer might stick shut temporarily due to dirt or spills, ice buildup or the normal functioning of the freezer's vacuum system. If you have trouble with a sticking door, troubleshoot the problem before replacing the gasket or calling a technician to replace the door.
Sugary spills such as juice or a buildup of grime on the gasket or the exterior of the freezer can cause the gasket on your freezer door to stick to the exterior of the freezer each time you open and close it. Dampen a cloth with warm soapy water and wipe down the gasket and the fridge exterior to remove any dirt or sticky substances. Dry with a clean towel and test the door. If the problem was a dirty gasket, your door shouldn't stick. To prevent sticking caused by a dirty gasket, clean your freezer exterior and the door at least once each month.
Petroleum Jelly to Prevent Sticking
Petroleum jelly is not ideal for preventing a sticking freezer door. Abrasive cleaners or those containing bleach or ammonia, scouring cleansers, waxes, concentrated dish or laundry detergent and flammable liquids should also be avoided. These products can damage both your refrigerator and freezer surfaces and the door gaskets. If you want to prevent a sticking door, use a thin coat of paraffin wax after cleaning your freezer door and gasket instead.
Opening your freezer door allows warm air to enter and cold air to escape. When you close the door, the air is cooled and its specific volume is reduced. This reduction creates a vacuum that keeps the door closed. It may seem like your freezer door is sticking when it is really just the vacuum system doing its job. Freezers with a vacuum-release device speed up the process of equalization and don't typically have problems with a sticking door, although some freezers use an airtight gasket seal that doesn't have this vacuum-release mechanism. This means that the door can't be opened and closed, and then opened again in rapid succession. Wait a few seconds after closing your freezer before trying to open it again to allow the air pressure inside the freezer to equalize.
Internal Ice Maker
If your freezer has a built-in icemaker, ice can build up on the ice maker sensor arm or in the water supply line. If a large enough block of ice builds, it can cover the door surface and this can cause the door to freeze shut after it's been closed for a while. To repair this problem, lift the sensor arm to turn off the ice maker and close the main water supply valve. Defrost your freezer and the ice maker to thaw the ice built up inside. Check the ice maker periodically and defrost the unit if you notice ice building up on the sensor arm or around the unit to prevent the problem.