Virtually all upscale freezers and refrigerator-freezer combos made by top-selling North American manufacturers include automatic defrost as a standard feature. Lower-priced freezers usually require that you manually defrost them by following specific procedures. They also cost less to operate because they employ simpler electrical components that consume less power.
Automatic defrosting freezers -- also known as frost-free models -- offer essentially maintenance-free performance. Auto-defrost components prevent the formation of frost by activating an internal heating system to deflect moisture away from the freezer compartment. This system avoids a build-up of ice you would normally have to remove manually in freezers without this feature.
Freezers without an auto-defrost feature require manual defrosting whenever frost or ice builds up on the freezer's internal walls. The simplest defrosting method consists of turning off the freezer and allowing the frost to melt away while the freezer door remains open. Make certain that freezer items stay frozen when defrosting manually.
Advantages and Disadvantages
Frost-free freezers are much simpler and more convenient to use, but have a couple of drawbacks. Auto-defrost freezers can partially dehydrate improperly wrapped foods, leading to freezer burn. In addition, automatic defrost models are the less energy-efficient choice, using an estimated 40 percent more electricity than manual defrost freezers.