What makes a refrigerator frost-free?

Answer by  alanmueller (83)

There are three basic parts. A timer.A heating coil. A temperature sensor. Approximately every six hours the time turns on the heating coil. The heater then melts all the ice off the cooling coils. Once this is accomplished the sensor turns the heater off, and the refrigerator normal cycle resumes.

Answer by  mrghx4 (12)

Frost is created when water vapor cools below freezing (32F). Since refrigerators are generally kept above freezing, you will never see frost in a refrigerator (only your freezer).

Answer by  LONGNE (121)

Frost free refrigerators have a defrost cycle that raises the temperature in the freezer just enough to keep ice from forming and building up. The theory is that the temperature won't be warm enough to thaw out the food, but it will be warm enough to melt any condensation thus keeping the formation of ice crystals to a minimum.