I have a Kelvinator C500 cyclic defrost frig. Always had a problem with ice forming around the two pipes coming from the back of the unit to the large white metal plate at the back of the cooling cabinet. These pipes are only short - about 4 inches but get a large build up of ice on them within 3 weeks of cleaning the frig and defrosting the ice off them. This has been an ongoing problem with the last 3 cyclic defrost friges I have had. Ay suggestions.

Yeah, call a service agent.