Condensor coils freezing up

I found the frig not cooling as good as it used to and did some research on the net and found some common failures. I started with the easiest test and ohmed out the defrost heater and also noticed it had blackened spots on both ends of element. The ohm reading confirmed it to be open. Replacement was easy for a "diesel" mechanic so basically anybody that can follow directions should be able to replace thiers as well.