The Damper. Cold air is produced in the freezer as liquid refrigerant passes through the evaporator coils and changes into gas. This process causes the surface of the evaporator coils to become extremely cold. A circulation fan blows air over the coils and through a vent into the refrigerator. Within the vent is a damper. The damper is a small flap that controls the flow of air from the freezer to the refrigerator. It is usually found in the top of the fridge or on the back panel near the top. The damper is controlled by a thermostat, which triggers it to open and close depending on the temperature of the air in the refrigerator.