There is described an air conditioning system with a refrigerant circuit, wherein the air conditioning system includes a leakage detection system. The leakage detection system comprises a room temperature sensor, an inlet temperature sensor for detection of a refrigerant temperature at a refrigerant inlet of a refrigerant evaporator, and an outlet temperature sensor for detection of a refrigerant temperature at a refrigerant outlet of the refrigerant evaporator. The sensors (34, 36, 40) are coupled with a calculating unit. In addition, there is described a method for leakage detection, in which a room temperature of the room to be air-conditioned is detected before the refrigerant evaporator on an air inlet side, a refrigerant inlet temperature is detected at the refrigerant inlet of a refrigerant evaporator, and a refrigerant outlet temperature is detected at a refrigerant outlet of the refrigerant evaporator.

Disclosed therein are a heat pump system for a vehicle and a method of controlling the heat pump system, which determines that frosting begins on an exterior heat exchanger and carries out a defrosting control if a difference value between outdoor temperature and refrigerant temperature of an outlet side of the exterior heat exchanger is above a frosting decision temperature in a heat pump mode, thereby increasing frost-prevention and defrosting effects and enhancing heating performance and stability of the system because the system recognizes the beginning of frosting on the exterior heat exchanger at a proper time so as to carry out the defrosting control.

The present invention relates to a vehicular heat management system capable of inducing an increase in refrigerant superheat degree without unconditionally turning off a compressor when the refrigerant superheat degree on the discharge side of a chiller is less than or equal to a lower limit value.

The vehicular heat management system includes: a compressor; a condensing heat exchanger; an expansion valve; an evaporation heat exchanger; and a control part configured to, when a refrigerant superheat degree on a discharge side of the evaporation heat exchanger is lowered to a predetermined lower limit value or less, control, step by step, at least two devices directly involved in the increase and decrease of the refrigerant superheat degree to increase the refrigerant superheat degree until the refrigerant superheat degree exceeds the lower limit value.

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 (ΔT.sub.w) of a change in an index indicating the temperature of the object of temperature regulation.

There is disclosed a vehicle air conditioner device of a so-called heat pump system to accurately perform efficient and comfortable heating of a vehicle interior. The vehicle air conditioner device includes a heating medium circulating circuit 23 which heats air to be supplied from an air flow passage 3 to a vehicle interior. A controller calculates a required heating capability TGQhtr of the heating medium circulating circuit to complement a shortage of an actual heating capability Qhp to a required heating capability TGQ of a radiator 4. The controller calculates a decrease amount ΔQhp of the actual heating capability Qhp from a difference ΔTXO between a refrigerant evaporation temperature TXO of an outdoor heat exchanger 7 and a refrigerant evaporation temperature TXObase in non-frosting, and adds the decrease amount ΔQhp to the required heating capability TGQhtr to execute the heating by the heating medium circulating circuit.

A vehicle heating, ventilating, and air conditioning (HVAC) system can be configured to reduce and/or prevent condensation build up on one or more elements of the system. Subsequent to a power state of the vehicle being switched from an active state to an inactive state, a fresh mode air source can be selected as an intake for a blower. It can be determined whether an ambient temperature is greater than or equal to a predetermined temperature. It can then be determined whether the compressor was in operation prior to the vehicle having been switched from the active state to the inactive state. It can be determined whether a temperature of an evaporator of the HVAC system is rising. If it is determined that the ambient temperature is greater than or equal to the predetermined temperature value, that the compressor was in operation prior to the vehicle having been switched from the active state tot eh inactive state, and that the temperature of the evaporator is rising, a blower can be activated to blow air from the fresh mode air source across the evaporator.

The present disclosure relates to a method of controlling a compressor, and may include: pilot driving which drives a compressor of an air conditioner by receiving a start signal; determining whether oil is short which compares the oil amount of the compressor, driven in the pilot driving, with a predetermined reference oil amount; normal driving which maintains the driving of the compressor when it is determined that the oil amount is the reference oil amount or more; and stopping which stops the driving of the compressor when it is determined that the oil amount is smaller than the reference oil amount. Accordingly, by stopping the compressor when the oil is short, it is possible to prevent damage to the compressor.

A control method of an air conditioning system for a vehicle includes a process A of determining whether arrival at a destination is imminent based on data detected from a data detecting unit by a controller and comparing a target temperature of an evaporator with an actual temperature of the evaporator in a state of cooling a vehicle interior while the vehicle is running. A process B includes controlling a blow motor, a compressor, and a vent discharge control unit by determining whether the evaporator is cleaned by the controller through process A, and controlling an outdoor air/indoor air mode operation unit by detecting external humidity and internal humidity. A process C includes controlling the blow motor and the outdoor air/indoor air mode operation unit by comparing an external temperature with the temperature of the evaporator.

The invention concerns a method for managing a thermal management device (1) for a motor vehicle, comprising the following steps: —increasing the speed of rotation of the compressor (3) to its maximum speed, —determining a modified setpoint temperature (T15-sp3) of the third element (300) greater than the first setpoint temperature (T15-sp1), so that the temperature of the second element (200) at the outlet of the first evaporator (11) tends towards its setpoint temperature (T11-sp), —adjusting the opening diameter of the second expansion device (13) so that the temperature of the third element (300) at the outlet of the second evaporator (15) reaches a modified setpoint temperature (T15-sp3), until the temperature of the second element (200) at the outlet of the first evaporator (11) reaches the setpoint temperature (T11-sp). The invention further relates to the thermal management device (1) for implementing said management method.

A thermal management method and system in a vehicle include a chiller to cause heat transfer between a coolant loop that defines a path in which a coolant circulates and a refrigerant loop that defines a path in which a refrigerant circulates. The system includes an electronic expansion valve (EXV) in the refrigerant loop to control a flow of the refrigerant into a first part of the chiller, and a coolant pump in the coolant loop to control a flow of the coolant into a second part of the chiller. A controller controls the EXV and the coolant pump based on a target amount for the heat transfer.