freezer tripping circuit?

Westinghouse f/f -17 yrs old perfect cond
Has started tripping power board every ONE AND HALF hrs? -have disc. all sockets and appliances -isolated to just f/f - even moved to another socket or 2 -still same
have cleared items from freezer fan vents
when unplugged f/f nothing trips
HELP
HELP AUSSIE, January 2018


done
found problem --paper dropped behind -blocked vents - overheated
sorted

happy, January 2018
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