Functional Diagram of Refrigerator Air Conditioner
1 - A/C compressor; 2 - Capacitor; 3 - Receiver-drier; 4 - Expansion valve; 5 - Evaporator; 6 - Evaporator of the rear air conditioner; 7 - Valve for shutting off the refrigerant of the rear air conditioner; 8 - Refrigerant injection valve for the rear air conditioner; A - high pressure (gaseous phase); B - High pressure (liquid phase); C - Low pressure (liquid phase); D - Low pressure (gaseous phase)
Additional heater. Diesel models
1 - Control unit of the heat transfer module; 2 - Burner housing; 3 - Coolant outlet; 4 - Combustion air purge module; 5 - Combustion air supply; 6 - Connector; 7 - Heat transfer module; 8 - Burner; 9 - Exhaust outlet; 10 - Coolant supply; 11 - Fuel supply; A6m2 - Combustion air purge; A6n1 - Additional heater control unit; A6r2 - Heater
Ventilation flows
The air supplied by the ventilation system to the passenger compartment through the filter can be heated or cooled, depending on the choice of the driver and passengers. The heater or air conditioner is located in the cabin, in the housing under the instrument panel. The entire flow of air supplied to the passenger compartment is directed for heating or cooling through the same casing. The temperature and air flow rate are regulated by means of the controls located on the control panel.
The heat generated during engine operation is transferred by the coolant to the heater radiator located in the passenger compartment. The intake airflow from the ventilation system passes through the radiator and is heated by the heat of the engine coolant flowing inside the radiator. The degree of heating is controlled by mixing in a certain ratio of cold and hot air using a mixing damper with a servo.
Used air is removed from the passenger compartment through vents with non-return valves.
The increase in air flow through the heat exchanger is provided by a fresh air fan.
If it is necessary to turn off the fresh air supply, for example in case of a bad smell, the system switches to circulation mode, in which only the air available there circulates in the passenger compartment.
Switching the system to the circulation mode is confirmed by the ignition of the control lamp.
Cabin air conditioning system
Work on the air conditioning system must be carried out by a specialist workshop. Never open the refrigerant circuit, as the refrigerant may cause frostbite if it comes into contact with the skin.
The air conditioning system can lower the interior temperature below the outside temperature. When the system is operating, the humidity in the passenger compartment decreases. In wet weather, the incoming fresh air is pre-cooled and then reheated to the set temperature. Thus, it is dried. With this procedure, the fogging of the glasses is removed.
The air conditioning system consists of a heater and a refrigerator. The KV refrigerator consists of a compressor, a condenser, a throttle, an evaporator, a refrigerant tank and pipelines. Refrigerant circulates in the system (type R134a), which, depending on temperature and pressure, can be in a liquid or gaseous state.
The air conditioner compressor is driven by the engine crankshaft through a ribbed belt. It creates pressure up to 30 atm. in the unit's refrigeration circuit, whereby the refrigerant, which is a gas, is heated. In the condenser, the refrigerant is cooled by the air flowing from outside (cooling air remains in the outside environment). As a result, the heated refrigerant condenses, turning into a liquid.
Having a lot of pressure, it is passed through the throttle, as a result of which its pressure drops. After that, the refrigerant evaporates in the circuit, while being strongly cooled. In the evaporator, the refrigerant removes heat from the air blown through it. As a result, the air is cooled. Cooled air enters the car interior. As a result of heating in the evaporator, the refrigerant turns into a gas and enters the compressor under low pressure, after which the circulation process is repeated.
Additional heater
An additional fuel-fired heater is installed on models with diesel engines. When the engine is started, it automatically starts to work depending on the temperatures of the coolant and the environment. Manual control is not provided. It can only be turned on or off with a switch on the center console.
In addition to the fuel-fired heater, an additional electric heater is also installed.