Abstract: A heat pump device includes an air conditioning control device configured to switch the heat pump device among a plurality of operation modes including an air-heating operation mode in which an indoor heat exchanger serves as a radiator and an outdoor heat exchanger serves as a heat absorber, and an air-cooling operation mode in which the indoor heat exchanger serves as a heat absorber and the outdoor heat exchanger serves as a radiator. The air conditioning control device switch a refrigerant pipe such that refrigerant is, in the air-cooling operation mode, supplied to part of the outdoor heat exchanger serving as a refrigerant inlet in the air-heating operation mode.

Abstract: A air conditioning control device is configured to estimate whether or not the temperature of refrigerant on a high-pressure side in a heat pump device is equal to or lower than a predetermined low temperature and to switch a flow path switching device to an air-heating start-up mode when it is estimated that the temperature of refrigerant on the high-pressure side in the heat pump device is equal to or lower than the predetermined low temperature and switch the flow path switching device to a normal air-heating mode when it is estimated that the temperature of refrigerant on the high-pressure side in the heat pump device is higher than the predetermined low temperature.

Abstract: A vehicle air conditioner comprising a heat pump device including a compressor that compresses refrigerant, first and second heat exchangers disposed inside the vehicle cabin within an interior air-conditioning unit, and a pressure reducing valve. The vehicle air conditioner further comprises an air-conditioning controller which controls the heat pump device and interior air-conditioning unit, an exterior heat exchanger temperature sensor and a degree-of-heating requested detecting section. If the quantity of heat absorbed by the exterior heat exchanger has decreased, the controller operates the heat pump device to operate in a mode in which a refrigerant discharged from the compressor flows through the first and second heat exchangers, bypasses the exterior heat exchanger, and then is sucked into the compressor, and a second mode in which the refrigerant is flow throughs the first heat exchanger and is bypassed around the second and exterior heat exchanger after pressure has been reduced.

Abstract: A heat pump device 20 is operated so as to make a switch between multiple operation modes including a first dehumidification and heating operation mode in which a refrigerant discharged from a compressor is circulated through a downstream interior heat exchanger 31, a first pressure reducing valve 52, an upstream interior heat exchanger 32, and an exterior heat exchanger 33 in this order so that the heat exchanger 31 functions as a radiator and the heat exchanger 32 functions as a heat absorber, and a second dehumidification and heating operation mode in which the refrigerant discharged from the compressor is circulated through the downstream interior heat exchanger 31, a second pressure reducing valve 53, the exterior heat exchanger 33, and the upstream interior heat exchanger 32 in this order so that the heat exchanger 31 functions as a radiator and the heat exchanger 32 functions as a heat absorber.

Abstract: A heat pump device includes an air conditioning control device configured to switch the heat pump device among a plurality of operation modes including an air-heating operation mode in which an indoor heat exchanger serves as a radiator and an outdoor heat exchanger serves as a heat absorber, and an air-cooling operation mode in which the indoor heat exchanger serves as a heat absorber and the outdoor heat exchanger serves as a radiator. The air conditioning control device switch a refrigerant pipe such that refrigerant is, in the air-cooling operation mode, supplied to part of the outdoor heat exchanger serving as a refrigerant inlet in the air-heating operation mode.

Abstract: A heat pump device includes an air conditioning control device configured to switch the heat pump device among a plurality of operation modes including an air-heating operation mode in which an indoor heat exchanger serves as a radiator and an outdoor heat exchanger serves as a heat absorber, and an air-cooling operation mode in which the indoor heat exchanger serves as a heat absorber and the outdoor heat exchanger serves as a radiator. The air conditioning control device switch a refrigerant pipe such that refrigerant is, in the air-cooling operation mode, supplied to part of the outdoor heat exchanger serving as a refrigerant inlet in the air-heating operation mode.

Abstract: If the quantity of heat absorbed by an exterior heat exchanger 33 has decreased, a switch is made into a first hot gas heating operation mode in which a refrigerant discharged from a motor-driven compressor 30 is allowed to flow through a downstream interior heat exchanger 31 and an upstream interior heat exchanger 32, bypass the exterior heat exchanger 33, and then be sucked into the motor-driven compressor 30 after its pressure has been reduced.

Abstract: A heat pump device 20 is operated so as to make a switch between multiple operation modes including a first dehumidification and heating operation mode in which a refrigerant discharged from a compressor is circulated through a downstream interior heat exchanger 31, a first pressure reducing valve 52, an upstream interior heat exchanger 32, and an exterior heat exchanger 33 in this order so that the heat exchanger 31 functions as a radiator and the heat exchanger 32 functions as a heat absorber, and a second dehumidification and heating operation mode in which the refrigerant discharged from the compressor is circulated through the downstream interior heat exchanger 31, a second pressure reducing valve 53, the exterior heat exchanger 33, and the upstream interior heat exchanger 32 in this order so that the heat exchanger 31 functions as a radiator and the heat exchanger 32 functions as a heat absorber.

Abstract: A air conditioning control device is configured to estimate whether or not the temperature of refrigerant on a high-pressure side in a heat pump device is equal to or lower than a predetermined low temperature and to switch a flow path switching device to an air-heating start-up mode when it is estimated that the temperature of refrigerant on the high-pressure side in the heat pump device is equal to or lower than the predetermined low temperature and switch the flow path switching device to a normal air-heating mode when it is estimated that the temperature of refrigerant on the high-pressure side in the heat pump device is higher than the predetermined low temperature.

Abstract: A heat pump device includes an air conditioning control device configured to switch the heat pump device among a plurality of operation modes including an air-heating operation mode in which an indoor heat exchanger serves as a radiator and an outdoor heat exchanger serves as a heat absorber, and an air-cooling operation mode in which the indoor heat exchanger serves as a heat absorber and the outdoor heat exchanger serves as a radiator. The air conditioning control device switch a refrigerant pipe such that refrigerant is, in the air-cooling operation mode, supplied to part of the outdoor heat exchanger serving as a refrigerant inlet in the air-heating operation mode.