Embodiments of the present invention provide a heat recovery system for an electric vehicle (1), comprising first and second switchable heat sources (65, 19) and a control means (20) operable to selectively switch one of the heat sources into thermal communication with a compressor (11) in a thermodynamic cycling system (12), the thermodynamic cycling system being in thermal communication with a heat sink (59, 159); and a detection means (39, 71, T3) operable to detect a temperature differential between each of the switchable heat sources and a fluid entering the compressor; wherein the control means is operable (adapted, arranged) to switch one of the first and second switchable heat sources into thermal communication with the thermodynamic cycling system when a temperature differential is detected between the fluid entering the compressor in the thermodynamic cycling system and the heat available from the switchable heat source, the temperature differential being such that the compressor (11) is operable to upgrade low grade heat from the switchable heat source (65, 19) to a higher grade heat upon operation of the compressor (11).

Embodiments of the present invention provide a refrigerant management system (10) in a heat flux management system (1) for an electric vehicle (150) and a method of refrigerant management, the system comprising a vehicle air conditioning circuit comprising a heat pump circuit (4) with a heating function and a refrigeration cycle refrigerant circuit (6), the air conditioning circuit comprising a heat pump condenser (17) in thermal communication with a heat source (19), a refrigerant evaporator (25) in thermal communication with the heat source (19), an evaporator (31) associated with an expansion valve (29), and a refrigerant compressor (11), wherein the components are fluidly connected to one another by a refrigerant line (9), an accumulator (37) fluidly coupled in the refrigerant line downstream of the heat pump condenser (17), the refrigerant evaporator (25) and evaporator (31) and upstream of the refrigerant compressor (11),

wherein the air conditioning circuit is switchable between a heating mode in which the heat pump circuit (4) is in fluid communication with the compressor (11) and the heat pump condenser (17) is isolated from fluid communication with the compressor (11) and a cooling mode wherein the refrigerant circuit (6) is in fluid communication with the compressor by actuation of at least one valve (15, 21, 41, 47);
wherein the air conditioning circuit comprises a sensor (39) at the compressor inlet (239) operable to monitor refrigerant temperature and pressure; and
wherein when the system is in the heating mode, a shut off valve 41 in line between the heat pump condenser (17) and the accumulator (37) is operable to open to initiate a cold start mode in which a temporary fluid communication is provided between the heat pump condenser (17) and the accumulator in the heat pump circuit when:
the sensor (39) detects one or both of: a superheated refrigerant at the compressor inlet (239) and a temperature gradient of more than 3 Kelvin between ambient (T3) and the compressor inlet (239).

There is disclosed a vehicle air-conditioning device in which a refrigerant subcool degree in a radiator is appropriately controlled, so that comfortable and efficient vehicle interior air conditioning is achievable. The vehicle air-conditioning device executes a heating mode in which a controller lets a refrigerant discharged from a compressor 2 radiate heat in a radiator 4, decompresses the refrigerant by which heat has been radiated by an outdoor expansion valve 6, and then lets the refrigerant absorb heat in an outdoor heat exchanger 7. In the heating mode, the vehicle air-conditioning device controls a refrigerant subcool degree SC of the radiator 4 by the outdoor expansion valve 6. On a basis of a radiator inlet air temperature THin that is a temperature of the air flowing into the radiator 4, the controller corrects a target subcool degree TGSC that is a target value of the refrigerant subcool degree SC in the radiator 4 in a lowering direction, as the radiator inlet air temperature THin rises.

An air conditioner includes a heat medium circuit, a refrigerant cycle device, a discharge capacity controlling section, a heat generation amount controlling section, a target temperature determining section, and an upper limit determining section. The heat medium circuit includes a heating heat exchanger and an electric heater. The refrigerant cycle device exchanges heat between a heat medium in the heat medium circuit and a refrigerant discharged from an electric compressor. During a heater priority mode, the rotational speed of the compressor is increased to reach an upper limit and a heating amount of the heater is increased as a temperature difference increases. During a compressor priority mode, the heating amount of the heater is decreased and the rotational speed is increased to compensate for a decreasing amount.

A vehicle air conditioner includes: a refrigerant circuit which includes a compressor, an external heat exchanger, an expansion valve, and an evaporator; and a cooling fan. The vehicle air conditioner further includes: a refrigerant temperature detection part; a vehicle environment temperature detection part; and a controller. The refrigerant temperature detection part is configured to determine the temperature of a refrigerant which flows into the expansion valve. The vehicle environment temperature detection part is configured to determine a temperature outside the refrigerant circuit under an installation environment. The controller is configured to control a speed of the cooling fan in a cooling operation time such that a cooling performance with respect to the external heat exchanger is decreased when the temperature difference between a determined refrigerant temperature by the refrigerant temperature detection part and a determined external temperature by the vehicle environment temperature detection part is equal to or less than a first set temperature difference.

Methods and systems for controlling a heating, ventilation, and air-conditioning (HVAC) intake. An air-conditioning control device receives the detected ambient air from an ambient air sensor, and the detected air temperature at a front of a condenser. The two temperatures are compared to determine whether to change the HVAC intake. In response to determining the air temperature at the front of the condenser is higher than the ambient air, the HVAC intake is placed into a recirculate position to allow air from the vehicle compartment to enter the HVAC intake.

Methods and systems for controlling a heating, ventilation, and air-conditioning (HVAC) intake. An air-conditioning control device receives the detected ambient air from an ambient air sensor, and the detected air temperature at a front of a condenser. The two temperatures are compared to determine whether to change the HVAC intake. In response to determining the air temperature at the front of the condenser is higher than the ambient air, the HVAC intake is placed into a recirculate position to allow air from the vehicle compartment to enter the HVAC intake.

A refrigeration system includes a startup mode control module that receives an off time of a compressor and an ambient temperature, determines whether the off time and the ambient temperature indicate that the compressor is in a flooded condition, and selects, based on the determination, between a normal startup mode and a flooded startup mode. A compressor control module operates the compressor in the normal startup mode in response to the startup mode control module selecting the normal startup mode, operates the compressor in the flooded startup mode in response to the startup mode control module selecting the flooded startup mode, and transitions from the flooded startup mode to the normal startup mode after a predetermined period associated with operating in the flooded startup mode.

There is disclosed a vehicle air conditioner which is capable of enlarging an effective range of a dehumidifying and heating mode to environmental conditions and smoothly dehumidifying and heating a vehicle interior. A vehicle air conditioner 1 executes a dehumidifying and heating mode in which a controller lets a refrigerant discharged from a compressor 2 radiate heat in a radiator 4, and decompresses the refrigerant by which heat has been radiated and then lets the refrigerant absorb heat in a heat absorber 9 and an outdoor heat exchanger 7, the controller decreases an outdoor blower voltage FANVout of an outdoor blower 15 and decreases an air volume into the outdoor blower 15 in a case where a temperature Te of the heat absorber 9 is high even when the controller adjusts a valve position of an outdoor expansion valve 6 into a lower limit of controlling in a situation in which a temperature TCI of the radiator 4 is satisfactory.

A refrigeration system includes a startup mode control module that receives an off time of a compressor of the refrigeration system and an ambient temperature, determines whether the off time and the ambient temperature indicate that the compressor is in a flooded condition, and selects, based on the determination, between a normal startup mode and a flooded startup mode. A compressor control module operates the compressor in the normal startup mode in response to the startup mode control module selecting the normal startup mode, in the flooded startup mode in response to the startup mode control module selecting the flooded startup mode, and transitions from the flooded startup mode to the normal startup mode after a predetermined period associated with operating in the flooded startup mode. The compressor is operated at a first speed in the normal startup mode and at a second speed in the flooded startup mode.