If the freezer is in a humid room be aware that adding insulation might allow water to condense between the foam and the freezer and accelerate rust.
Chest freezer lid insulation.
If the outside of your freezer gets warm when the compressor is running better not insulate it.
A good closed cell foam should work just fine.
Chest freezer that got unplugged accidentally and the resulting humidity caused the insulation plastic and gasket of the lid to fail.
These steps show how to replace the lid gasket on kenmore frigidaire gibson crosley white westinghouse and kelvinator chest freezers.
You could probably also use a roll of fiberglass insulation as well.
Either way you just want something that will keep the cold away from contacting the lid and won t absorb moisture.
The plastic piece that holds the gasket insulation in place has cracked catastrophically and now i have a functional chest freezer that has no lid insulation.
To make it fit snug again you can use some small washers placed under some new retainers 5306599968.
It will insulate and impede air leaks.
Feel around the lid for leaks and fix them.
Lid for chest freezer i have a 21 cu.
I think most models are made this way at present.
The lid contains wiring for lights and switches and the ice surrounding the wiring harnesses causes trickle currents which trips gfi breakers.
It might be beneficial to just lay a heavy blanket over the lid instead of foam.
If the lid gasket is torn or damaged thick frost forms on the food and inner freezer walls.
Replace a damaged or torn lid gasket with the manufacturer approved replacement part.
The insulation will prevent the transfer of heat to the outside air.
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