An insulated icemaking compartment is provided in the fresh food compartment of a bottom mount refrigerator. The icemaking compartment may be integrally formed with the liner of the fresh food compartment, or alternatively, may be modular for installation anywhere in the fresh food compartment. A removable bin assembly with a front cover normally seals the icemaking compartment to maintain the temperature in the compartment. A cold air duct formed in the rear wall of the refrigerator supplies cold air from the freezer compartment to the icemaking compartment. A return air duct directs a portion of the air from the icemaking compartment back to the freezer compartment. An air vent with a damper in the icemaking compartment directs another portion of air into the fresh food compartment. A control system provides for controlling refrigerator functions in a manner that promotes energy efficiency, including movement of the damper between open and closed positions.