5.3.1. General information and security measures

General information and security measures

General information

See also Part of the Device of ensuring comfort of the Head Governing bodies and methods of operation.

Works on service of system have to be performed in the conditions of a specialized workshop.

Function chart of the K/V typical system

1 — the heater Fan
2 — the Evaporator
3 — the Broad valve
4 — the Receiver dehumidifier
5 — the condenser Fan
6 — the Condenser
7 — the Compressor
and — External air
b — the heated air which is Taken away outside

with — not cooled air forced by the fan
d — the Cooled air coming to salon
And — Gas of high pressure
In — Liquid of high pressure
With — Liquid of low pressure
D - Gas of low pressure

Do not open a working contour at all To/in, - at contact with skin coolant can cause a frostbite!

The air given by system of ventilation to interior of the car can be warmed up or cooled depending on the choice of the user. The heat exchanger of a heater and the K/V evaporator settle down in salon, under the dashboard. All stream of the air given to salon goes for heating or cooling through the same casing. Temperature and speed of a stream of air is regulated by means of the governing bodies located on the control panel.

The principle of management of the choice of temperature condition (on the example of the mode of intensive warming up of salon)

The list of the main components of systems of heating and air conditioning of salon with the short description of their appointment and the principles of functioning is given below.

The operating shutdown relay To/in

This relay carries out a role of the electric switch closing a chain of coupling of the К/В compressor. At achievement by temperature of cooling liquid of some critical value the module of engine management (ECM) develops special team according to which this relay makes shutdown of air conditioning system. Five-second compulsory shutdown of the K/V compressor can be also initiated by the module of management at start of the engine, and also in the mode of slow dispersal. The relay is among the replaced components.

The forcing fan

Due to rotation of a krylchatka of the forcing fan air supply on an entrance of the heat exchanger of the K/V evaporator further given to interior of the car according to the installations chosen by the operator is provided (with a preliminary transmission through the heater heat exchanger, or bypassing the last).

Electric motor of the drive of the forcing fan

The choice of the high-speed mode of an electric motor is carried out by the operator from the control panel of functioning of systems of heating/air conditioning. At the operating handle turned in situation by OFF the chain of grounding of an electric motor remains opened and the fan does not function. In the first (LO) position of the handle force of the current given on an electric motor is limited to three resistors of special resistive assembly, as a result, the krylchatka of the fan rotates in the low-speed mode. Further switching between the modes M1, Sq.m and HI provides step-by-step decrease in resistance of resistive assembly with the corresponding increase in speed of rotation of a krylchatka.


The compressor provides the movement of coolant in a refrigerator path of the air conditioning system. The compressor is located at the left on the block of the engine and is put in action by the belt drive from a pulley of a bent shaft of the last (through the operating clutch coupling). Basic elements of the compressor are actually compressor knot distributing knot, the operating clutch coupling and a driving pulley.

Compressor clutch coupling

The clutch coupling To/in serves as the executive mechanism operating activation of the compressor. The coupling is magnetic and provides activation/deactivation of the compressor at the command of the operator from the switch on the control panel, and also according to the special teams developed in certain conditions by the module of engine management (ECM). The clutch coupling of the compressor is among the maintainable and replaced components.


The condenser is installed ahead of a radiator of the cooling system and is the air and liquid heat exchanger providing heat removal from a working body (coolant) of a refrigerator path of air conditioning system. Intensity of functioning of the condenser is provided at the expense of a prokachivaniye through the heat exchanger of the additional air forced by the special fan. The condenser is also among the maintainable and replaced components.

Condenser fan

The fan provides adequate selection of heat from the coolant condenser which is pumped over through the heat exchanger even at the motionless car when the running air stream completely is absent. Food on a driving electric motor of the fan moves via the special operating relay.


The K/V evaporator is placed in the general with the forcing fan, and the operating shutdown relay To/in a casing. The evaporator consists from working by the principle, the return principle of functioning of a radiator of the cooling system, heat exchanger and broad valve.

Evaporator heat exchanger

Getting to the evaporator coolant boils, intensively selecting heat from the air banished through the heat exchanger by the forcing fan. Sharp cooling of an air stream is followed by condensation to the moisture which is contained in it. Condensate drops out on heat exchanger plates from where then it is taken away on a drainage path. Thus, the evaporator, besides the cooling function, plays also a dehumidifier role. The heat exchanger is among the maintainable and replaced components.

Broad valve

The valve provides adiabatic expansion of the high pressure of coolant which is in a phase of liquid at hit it in the evaporator. Such expansion considerably increases intensity of the heat sink from the air banished through the heat exchanger. At the same time the valve exercises control of a consumption of the coolant coming to the evaporator, allowing to avoid a heat exchanger flood.

Air inlet gate servo-driver

At activation of the air circulation mode by the operator from the control panel the special servomotor provides removal of the managing director of the gate blocking a path of giving in salon of fresh air. Activation of such mode allows to avoid penetration into the car badly of the smelling air, and also to carry out intensive cooling of the salon filled with air, heated by direct sunshine during the parking of the car.

The mode of circulation has to be activated only for insignificant time as the air which is repeatedly banished on the closed cycle quickly becomes stuffy.


The air drained in the evaporator is banished through the heater heat exchanger. Warming up of air is carried out due to selection of heat from the hot heat carrier of the cooling system of the engine banished via the heat exchanger. The choice of temperature condition is carried out by the operator by rotation of the corresponding handle operating position of the mixing gate regulating a consumption of the air banished through a heater.

Connecting hoses and lines of a refrigerator path

Connection among themselves of working elements of the K/V system is carried out by means of the whole complex of the flexible hoses and metal lines which are used, respectively, in low pressure and high-pressure contours of a working path of air conditioning system. Lines of communication of a refrigerator path are among the replaced components.

Receiver dehumidifier

The receiver dehumidifier is located on an exit from the condenser and carries out accumulation of liquid coolant and removal of the moisture which is present at it. Further, the drained working body comes to the evaporator.

Service unions

The equipment of a refrigerator path service ports allows to carry out a discharge and charging of the К/В system. The service union of a contour of high pressure is built in the metal line of communication leaving a receiver dehumidifier. The low pressure service union is switched on in a piece of the flexible hose connecting the returnable line of the evaporator to the compressor.

Security measures at service of components of air conditioning system

The working path of the K/V system is under pressure! Do not try to disunite any nipple I will corrode or to remove separate components without preliminary discharge of system in the conditions of a specialized workshop. As a working body in system coolant of the R134a type is used, - make sure that at the station there is a necessary equipment suitable for use at service of air conditioning systems using coolant of this type. At a rassoyedineniye of nipple sockets of a refrigerator path surely put on goggles!

Service of air conditioning system has to be made only by forces of specially trained staff trained in safe working methods with use of the appropriate equipment with observance of the rules of depressurization acquainted with methods of collecting and order of storage of automobile coolant.