Saab 9-5

since 1997 of release

Repair and car operation

Systems of heating, ventilation and air conditioning

General information

Description of systems

The design of systems of ventilation with a heater and To/in is presented on an illustration.

Design of system of ventilation with a heater and To/in

The salon is divided into two zones, – the driver and passengers, – for each of which it is possible to establish individual parameters of ventilation, heating and air conditioning, except a circulation mode. Management of ventilation system with a heater and To/in is given in Head Governing bodies and operation receptions.

Hot OZh is passed via the heat exchanger, heating up air passing through it. Supply of air in salon is regulated by zaslonka. If to turn on the heater fan, air will move in salon more intensively. The fan can work with different speed. At the closed zaslonka of OZh arrives on a small contour back in a contour of a radiator of the engine.

Before getting to salon, air passes through the filter in which the main share of a dust settles. It is necessary to observe periodicity of replacement of the filter since the dusty filter limits supply of air that will lead to an air stagnation in salon. In addition the coal filter clearing air of final gases of diesel engines, etc. can be established.

Distribution of streams of air of system of ventilation is carried out also with the help a zaslonok. On all models the air circulation mode is provided.

Air leaves salon through two ventilating openings, located in a back part of the car.

Air central air (To/in) enters into a standard complete set of some models, and on other models can be established in addition. Besides, the system of automatic control by a heater and In (ACC) can be established. Components of ACC system are specified illustrations.

Arrangement of components of ACC system

Works with To/in system should be carried out in a specialized workshop. Do not open a contour of circulation of a coolant as at contact with skin the coolant can cause frostbite.

By means of To/to system air temperature in salon it is possible to lower rather external temperature. At system work humidity of air in salon decreases. In the crude weather, arriving fresh air previously it is cooled, then again heats up to the set temperature. Thus its drainage is made. By means of this procedure it is possible to get rid of a zapotevaniye of glasses.

Components of To/in system and their arrangement are specified illustrations.

Arrangement of components of To/in system

In system the coolant (R134á type) which depending on temperature and pressure can be in a liquid or gaseous state circulates. The schematical description of streams of a coolant is provided on an illustration.

Coolant streams in To/in system

The compressor of the conditioner is given by a belt from a cranked shaft of the engine. He creates pressure in a contour of the coolant representing gas, and causes its heating. In конденсаторехладагент it is cooled with external air. Thereof the warmed-up coolant passes to a liquid phase. Then under a high pressure the coolant is passed via the broad valve therefore pressure of a coolant falls. After that the coolant evaporates in a contour, at the same time strongly being cooled. In the evaporator the coolant selects heat from air blown through it. Thereof air is cooled and arrives in car salon. As a result of heating in the evaporator the coolant turns into gas and under low pressure arrives in the compressor then process of circulation repeats.

Design of the broad valve

On model with the diesel V6 engine the additional heater working at diesel fuel can be established. Besides, for increase in a water stream through a radiator of a heater of the models delivered on the markets with a frigid climate, the circulating pump (see an illustration the Design of system of ventilation with a heater and To/in) can be established.

Design of an additional heater

Security measures at To/in system service

The To/in system should be served by exclusively prepared technicians trained in safe working methods with use of the appropriate equipment and with observance of rules of depressurization, and also acquainted with receptions of collecting and storage of an automobile coolant.

1. Do not allow contact of a coolant to skin;
2. At work near To/in system put on goggles;
3. At coolant hit on skin or in eyes do not pound the struck place. Immediately wash out the struck site cold water within not less than 15 minutes. Immediately address for medical care in medical institution. Self-treatment is not allowed;
4. The coolant is stored in a new cylinder under pressure. Store a cylinder at temperature not above the +50th hail. Take the measures excluding falling of a cylinder from height or other situations which can lead to its damage;
5. Works should be carried out in well aired room. The coolant quickly evaporates, leads to reduction of access of oxygen and the complicated breath;
6. The gaseous coolant is heavier some air and rather quickly should gather below, for example, under the car;
7. At combustion of a coolant poisonous gas is formed. Store a coolant far from open sources of fire. Do not smoke at work with To/in system;
8. At carrying out welding works near To/in system do not subject to its influence of high temperature or an open flame. The overheat can lead to pressure increase in system and to ignition;
9. Condenser or evaporator cleaning by means of water vapor is not allowed. It is necessary to use only cold water or the compressed air.