17 year camco Fridge (freezer on bot) not defrosting

[itsBroke]

Model Number: ccc18habbww
Brand: GE
Age: More than 10 years

Have a 17 year old fridge which is having issues defrosting

think the fan may now be always on (not 100% sure as I've only been keeping an eye on it for a few hours (never kept track of the fan before; but pretty sure it wasn't running all the time. Could be that the fridge is just re-balancing the temperature as I've had it off for a bit)

Eventually the coils freeze completely and stops air flow which causes the upper fridge to warm up.

Have unplugged and dethawed the coils with a hair dryer.

Checked the heating element which looks to be ok and shows resistance when checked with a meter.

I have another offer for a free (also older fridge) from my brother; but before I swap it, was just wondering if anyone would have any ideas on what could be wrong (Would rather buy a part and fix it than have to swap it out :-)

Its made By Camco which I believe related to G.E. (Was built in Hamilton Ontario)

Model is: ccc18habbww

Thanks

Paul

[itsBroke]

Morning Update

Fridge may be ok. After thawing it out and running it over night, there was water released (attached the exit hose to a bucket)

So maybe a fluke freeze up, or a sign of things to come if the form of a "starting to fail" component.

Maybe Should be replaced :-( but I think I have some time (Was also looking into a new fridge; but the quality doesn't seem to be there. Looks like the times of 20 year appliances have come to a end)

Paul