All new refrigerators and air conditioners use refrigerants that are less harmful to the ozone layer.all new refrigerators and air conditioners use refrigerants that are less harmful to the ozone layer Before anything goes in the freezer, make sure it is wrapped and/or packaged appropriately. This will vary according to the item you are freezing. Meats should be wrapped in plastic and foil, or in an appropriately sized freezer bag with excess air removed. Plastic storage containers should be appropriately sized for the contents but not overfilled. Liquids expand with time and may push up that lid during initial freezing.Every once in a while check the seal on what is in the freezer to make sure all is still okay.The great variety of spare parts poses the biggest challenge, since the availability of parts.Process reliability have to be guaranteed.