An air conditioner for a vehicle includes a refrigeration cycle, a heating unit and a control unit. The refrigeration cycle includes an air-conditioning evaporator, a chilling evaporator, an air-conditioning side flow path, a detour flow path and an air-conditioning flow rate adjustment unit. The control unit includes a determination unit that determines whether a condensation condition is satisfied when a refrigerant is flowing through the chilling evaporator via the detour flow path in a state where an inflow of a refrigerant into the air-conditioning evaporator is prohibited. When the determination unit determines that the condensation condition is satisfied, the control unit controls the air-conditioning flow rate adjustment unit to allow an inflow of a refrigerant into the air-conditioning evaporator as a condensation suppression operation for suppressing condensation of a refrigerant in the air-conditioning evaporator.

A vehicle air conditioning device is provided which is capable of accurately judging the need for temperature regulation of an object of temperature regulation mounted in a vehicle and efficiently performing temperature regulation. A compressor 2 to compress a refrigerant, an indoor heat exchanger (radiator 4 and heat absorber 9) for exchanging heat between air supplied to a vehicle interior and the refrigerant, an outdoor heat exchanger 7 disposed outside the vehicle interior, and a control device 11 are provided to perform air conditioning of the vehicle interior. An equipment temperature adjusting device 61 for adjusting the temperature of the object of temperature regulation mounted in the vehicle is provided. The control device controls the equipment temperature adjusting device 61 on the basis of a gradient (ΔTw) of a change in an index indicating the temperature of the object of temperature regulation.

An evaporator apparatus for a refrigeration cycle of an HVAC system or a refrigeration system is disclosed that includes: a primary evaporator pathway for a working fluid of the refrigeration cycle extending through a primary expansion device and a primary evaporator; a secondary evaporator pathway for the working fluid in parallel with the primary evaporator pathway and extending through a secondary expansion device and a secondary evaporator; a coolant circuit for cooling a device, the secondary evaporator configured for heat exchange between the working fluid and process fluid of the coolant circuit; and a controller configured to control: the primary expansion device to maintain a target superheat of working fluid at a primary control location downstream of the primary evaporator; and the secondary expansion device based on monitoring a temperature of process fluid to maintain a target temperature of process fluid at a coolant control location in the coolant circuit.

When a temperature of a coolant is a first predetermined temperature or higher, an air conditioner ECU executes a first control that sets a target evaporation temperature higher by a predetermined temperature and the air conditioner ECU executes a second control that changes the target evaporation temperature in accordance with a cooling load inside the vehicle cabin. When the second control is executed after the first control is executed, the air conditioner ECU sets a first target evaporation temperature set by the first control as the target evaporation temperature, and calculates a second target evaporation temperature that is changed by the second control based on the target evaporation temperature immediately before the first control is executed. When the second target evaporation temperature becomes larger than the first target evaporation temperature, the air conditioner ECU sets the second target evaporation temperature as the target evaporation temperature.

A control unit that controls a travelling state and an air conditioning state of a vehicle includes: a drive control unit performing a vehicle speed control and a power train control, the vehicle speed control selectively executing an acceleration operation where an engine mounted on the vehicle is operated and a deceleration operation where the engine is stopped to allow the vehicle to coast, the power train control selectively executing activation or deactivation of the engine; m and an air conditioning control unit that controls an air conditioning system provided in the vehicle to execute an air conditioning control. A content of control is changed for at least one of the vehicle speed control, the power train control and the air-conditioning control while the air conditioning system is operating, compared to a case where the air conditioning system is not operating.

A vehicle air-conditioning apparatus is provided which is capable of expanding an effective range of a dehumidifying and heating mode to achieve comfortable vehicle interior air conditioning. A control device (controller) executes a dehumidifying and heating mode to let a refrigerant discharged from a compressor 2 radiate heat in a radiator 4, let a part of the refrigerant flow from a bypass circuit (refrigerant pipe 13F) to an indoor expansion valve 8, and let the residual refrigerant flow through an outdoor expansion valve 6. In the dehumidifying and heating mode, the control device has a state of controlling the operation of the compressor 2, based on a heat absorber temperature Te and executes a radiator temperature priority mode which enlarges a capability of the compressor when heat radiation in the radiator is insufficient.

A refrigerant management system in a heat flux management system for an electric vehicle and a method of refrigerant management is provided. The system includes a vehicle air conditioning circuit including a heat pump circuit and a refrigeration cycle refrigerant circuit, the air conditioning circuit including a heat pump condenser in thermal communication with a heat source, a refrigerant evaporator in thermal communication with the heat source, an evaporator associated with an expansion valve, and a refrigerant compressor where the components are fluidly connected to one another by a refrigerant line. An accumulator is fluidly coupled in the refrigerant line downstream of the heat pump condenser, the refrigerant evaporator and evaporator and upstream of the refrigerant compressor, and the air conditioning circuit is switchable between a heating mode and a cooling mode in which the refrigerant circuit is in fluid communication with the compressor by actuation of at least one valve.

A refrigerant circuit system includes a compressor configured to compress refrigerant, a condenser configured to cause the compressed refrigerant to radiate heat, first and second evaporators each configured to decompress and expand the heat-radiated refrigerant by regulating a valve opening degree, first and second evaporators provided in parallel and configured to cause the refrigerant, respectively decompressed and expanded by the first and second expansion valves, to absorb heat, and a controller configured to, based on first information related to a temperature of a first temperature regulated object, regulated by the first evaporator, second information related to a temperature of a second temperature regulated object, regulated by the second evaporator, and third information related to a degree of superheat of the refrigerant at an inlet of the compressor, control the valve opening degrees of the first and second expansion valves and a compression ratio of the refrigerant by the compressor.

A method for operating a coolant circuit of a refrigeration system of a vehicle having multiple system sections. A single pressure sensor is located in each system section. A temperature sensor is arranged downstream at each component to be balanced in the system sections, such as heat exchangers and a coolant compressor. The sensor signals of the pressure and temperature sensors are supplied to a control unit for the control or regulation of the refrigeration system. Furthermore, a pressure approximation value at the position of the temperature sensor is calculated by a pressure loss value determined using a pressure loss calculation function starting from the position of the pressure sensor arranged in the system section of the component up to the position of the temperature sensor if the temperature sensor and the pressure sensor are arranged at different positions in the system section.

A vehicle air-conditioning device is a heat pump type vehicle air-conditioning device including an external heat exchanger that performs heat exchange between refrigerant flowing the inside thereof and outside air. With the vehicle air-conditioning device, a controller functions as a temperature-difference calculation unit that calculates the temperature difference ΔT between the refrigerant in a refrigerant flow path on the exit side of the external heat exchanger and the outside air, and in addition, the controller functions as a frost formation determination unit that determines that frost formation is caused on the external heat exchanger on the basis of the elapsed time to of a state in which the temperature difference ΔT is equal to or larger than a frost-formation temperature difference at which the frost formation may be caused on the external heat exchanger.