Martin wrote:
I can see that icing in the freezer is linked to air leakage past the top of
the door seal. As the seal contains a magnetic strip embedded in
plastic, I can't envisage what could possibly wear or age over time, which
makes me think it would be pointless replacing the seal; there are no moving
parts and I doubt the magnetic strip loses its effect over time.

So do these door seals lose their capacity to seal over time and, if so,
what is the mechanism of this ageing/wear process?

Yes, and it is simply aging -- they lose their flexibility so they don't
seal as well as they may not be able to "reach" far enough for the
magnet to make firm contact.

Also, it's possible the door hinges have worn and are letting the door
sag or not close evenly which results in the seals not having enough
"stretch" to allow them to mate. An adjustment there can fix/alleviate
the problem at least in the short term. May eventually still need new
seal(s) or hinge(s) depending on the type and what is/isn't adjustable
for the particular model...

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