Zero is the correct temperature for the freezer. With that said the freon is within a sealed system. if it leaks you are probably in need of a new refrigerator. '
Start checking the basics.
Are the condenser coils dirty and in need of cleaning? This is a very common problem with any domestic refrigerator.
Is the fan that blows over the condensing coils operating. Usually, you can hear it running at the bottom front. You can remove that small grill at the bottom front and usually see the coils also if they are filthy with dust.
Is the fan in the freezer compartment blowing??
are the evaporator coils frozen over? Another common problem. Usually located behind the rear of the freezer compartment if its a side by side. If you see ice on the freezer compartment where the coils are located its probably frozen over.
finally, it can be a thermostat problem.
All can be figured out by searching each problem individually on the internet.
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