Disclosed are climate systems for vehicles and methods for controlling the climate systems. In some implementations, a climate system includes: (1) a temperature sensor configured to measure a temperature within the compartment of the vehicle; (2) a first compressor powered by an engine of the vehicle to compress a refrigerant; (3) a second compressor driven by an electric motor to compress the refrigerant; and (4) a controller electrically coupled to the first compressor and the second compressor. The controller configured to: (1) calculate a thermal load of the compartment based on a difference between a desired temperature and a measured temperature; and, (2) based on the calculated load, selectively activate: (i) the engine, (ii) the first compressor, and/or (iii) the second compressor.

Methods and systems for providing control of a heat pump of a motor vehicle are presented. In one operating mode, speed of a heat pump compressor is controlled responsive to an outlet pressure of the heat pump compressor. In a second operating mode, speed of the heat pump compressor is controlled responsive to a pressure ratio between an inlet and an outlet of the heat pump compressor.

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.

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.

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 HVAC system for a vehicle that includes a propulsion system, a frame, a passenger compartment, and a door coupled to the frame. The HVAC system includes a refrigeration circuit that selectively controls the temperature of the passenger compartment based on a sensed temperature within the passenger compartment. The refrigeration circuit includes an exterior heat exchanger, a first air moving device coupled to the exterior heat exchanger, an interior heat exchanger, a second air moving device coupled to the interior heat exchanger, and a compressor. The HVAC system also includes a controller that is operable to detect a condition of the vehicle that includes at least one of a position of the door, a location of the vehicle, and a load of the propulsion system. The controller is programmed to adjust the refrigeration circuit in response to the sensed passenger compartment temperature and the detected vehicle condition.

Methods and system for operating a heat pump in different operating modes and providing a predictable heat pump response when the heat pump is transitioned between the different operating modes are presented. In one example, a controller that includes executable instructions for providing a bumpless compressor command for operating the heat pump is disclosed.

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 method of controlling a transport refrigeration system including a refrigeration unit including a compressor, and a refrigerated compartment operably coupled to the refrigeration unit, and the transport refrigeration system is operable in a standby mode in which the transport refrigeration system is connected to and powered by a mains power source, the method including providing a first compressor speed, wherein the first compressor speed is less than a maximum speed of the compressor of the refrigeration unit; determining when the transport refrigeration system is being operated in the standby mode; determining whether a current time is within a first time period; and when it is determined that the transport refrigeration system is being operated in the standby mode, and when it is determined that the current time is within the first time period: operating the compressor of the refrigeration unit in accordance with the first compressor speed.

A transport refrigeration unit system (26) for cooling a trailer compartment (24) is provided. The transport refrigeration unit system (26) includes an engine for controlling a cooling rate capacity, the engine operable at a nominal high speed and a nominal low speed. Also included is a controller (50) in operative communication with the engine to control an engine speed of the engine. Further included is a user interface (52) in operative communication with the controller (50), the user interface (52) providing a high capacity cooling mode to a user, wherein initiation of the high capacity cooling mode includes the engine operating at a speed greater than the nominal high speed to result in a high capacity cooling rate.