Vehicle air conditioner

A vehicle air conditioner comprising:

• a compressor which compresses a refrigerant;
• an air flow passage through which air to be supplied to a vehicle interior flows;
• a radiator which lets the refrigerant radiate heat to heat the air to be supplied from the air flow passage to the vehicle interior;
• a heat absorber which lets the refrigerant absorb heat to cool the air to be supplied from the air flow passage to the vehicle interior;
• an outdoor heat exchanger disposed outside the vehicle interior to let the refrigerant radiate heat or absorb heat;
• and
• control means,
• the vehicle air conditioner executing at least a heating mode in which the control means lets the refrigerant discharged from the compressor radiate heat in the radiator, decompresses the refrigerant by which heat has been radiated, and then lets the refrigerant absorb heat in the outdoor heat exchanger,
• the vehicle air conditioner comprising:
• auxiliary heating means for heating the air to be supplied from the air flow passage to the vehicle interior,
• wherein the control means has frosting estimation means for estimating frosting to the outdoor heat exchanger, and when the heating mode is executed in a state where a power is supplied from an external power source to the compressor or a battery which supplies the power to drive the compressor, the control means executes the heating mode by the auxiliary heating means, in a case where the frosting to the outdoor heat exchanger is predicted based on the estimation of the frosting estimation means,
• wherein the frosting estimation means calculates a maximum heating capability predicted value without frosting TGQhpNfst which is a target value of the maximum heating capability generable by the radiator in a range in which the outdoor heat exchanger is not frosted, and
• the frosting estimation means predicts that the outdoor heat exchanger is frosted in a case where the maximum heating capability predicted value without frosting TGQhpNfst is smaller than a required heating capability Qtgt as the heating capability of the radiator which is required or a value of Qtgt-α1, wherein the α1 is a value to impart a margin to the frosting, and
• wherein the frosting estimation means calculates the maximum heating capability predicted value without frosting TGQhpNfst on the basis of an outdoor air temperature, or time, solar radiation, a rainfall, a location and weather conditions in addition to the outdoor air temperature.