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Ventilation systems, heating and air conditioning
 | See. Some also comfort the Head Controls and operation receptions. |
Air supplied the ventilation system into the passenger compartment through the filter can be heated or cooled, depending on the choice of the driver and passengers. Heater or air conditioner located in the cabin, in the case under the dashboard. The entire flow of air submitted to salon is sent for heating or cooling through the same casing. The temperature and flow rate of air is regulated using the controls on the control panel. The heat generated when the engine is transmitted to the coolant radiator located in the cabin heater. The supplied air flow from the ventilation system passes through the cooler and heated by the heat of the engine coolant flowing in the radiator. The degree of heating is adjusted by blending in a specific ratio of cold and hot air by mixing flap valve. Used air is removed from the passenger compartment through the vents with non-return valves. Increasing the air flow through the heat exchanger fan provides fresh air. If you want to turn off the supply of fresh air, for example, a bad smell, the system switches to recirculation mode, in which circulates in the cabin air is only available there. Switching system in circulation mode is confirmed by the activation of a control lamp (see chap. Controls and receptions of safe operation). The air conditioning system cabin Driving circuit of the air conditioner Functional diagram of a typical air conditioning system shown in the illustration. Work on the air-conditioning system should be carried out a specialized workshop. In no case do not open the refrigerant circuit, as in contact with skin refrigerant can cause frostbite. With air-conditioning system in the cabin air temperature can drop below the ambient temperature. When the humidity inside the system decreases. In wet weather the incoming fresh air is pre-cooled, and then reheated to a predetermined temperature. Thus it is done draining. Using this procedure removes misting. The air conditioning system includes a compressor, a condenser, a throttle, an evaporator, a refrigerant tank and connecting conduits. The air conditioning system includes a condenser positioned in front of the radiator, an evaporator, located in the general housing with heat exchanger of a heater, a compressor, the receiver / dryer and refrigerated tubes connecting the above components. Evaporator inlet damper set providing differential pressure required to operate the system. As a working fluid path system K / V type R134a refrigerant is used, it changes its aggregate state depending on the combination of defining parameters (temperature and pressure). The fan supplies air to the cabin evaporator operates on the principle, the principle of reverse operation of the radiator, the carburetor heat is removed from the air and is transferred to the refrigerant. Heating, the refrigerant evaporates at the evaporator outlet passes to a gaseous state. Conditioner compressor is driven in rotation by the crankshaft of the engine via a belt transmission and provides in the working path of the excess pressure to 30 atm. As a result of the adiabatic compression in the gaseous state refrigerant is heated. Proceeding in a refrigerant cooled condenser through-flow of outside air, and condensing, in the box becomes a high pressure liquid. When passing through the throttle pressure liquid refrigerant is discharged. Then, the refrigerant evaporates in the circuit, and at the same time strongly cooled by passing through the evaporator removes heat from the blown air therethrough. The cooled air is supplied to the interior of the vehicle. By heating the refrigerant in the evaporator is transformed into low-pressure gas, and is returned to the compressor and then circulating process is repeated. Safety precautions when servicing the air conditioning system components  | The system is under pressure! Do not attempt to disconnect any pipes related to the air conditioning system, without removing it from the working fluid. Removing fluid from the system - a rather complex operation that should be performed at a service station. The system refrigerant is R134a type. Make sure that the station has a need for this type of refrigerant equipment. Wear protective glasses, disconnecting the tube system. |
The air conditioning system should be serviced exclusively prepared technicians trained in safe work, using proper equipment in compliance with the rules of depressurization, familiar with the methods of collection and storage procedures automotive refrigerant. - Refrigerant R134a, used at the moment, much less aggressive than previously used type of refrigerant R12. However, it is very dangerous to health. Avoid contact with eyes or skin - you can get burned. Although it is not toxic, its vapors can cause suffocation - do not remove it from the system, while indoors. Its vapors are heavier than air, so are not under the car when it is removed from the system;
- Do not allow refrigerant vapor to open flame. With his burning, poisonous gas. Gas mixed with air in certain proportions, can become explosive. Inhalation of vapors through a lit cigarette can lead to tragic consequences;
- Do not allow refrigerant to the atmosphere. In contrast to the R12 refrigerant type R134a does not cause depletion of the ozone layer, but leads to the greenhouse effect in the atmosphere;
- The system uses a seal made of a special material designed for use with a given type of refrigerant (for 134a - green). In order to make sure we do not mix different types of refrigerants for fueling a certain type of refrigerant used a certain type of adapters;
- Discharge system should be carried out in the workshop Mercedes-Benz;
- Before carrying out any work related to the heating of any units of the car (welding, soldering, drying after painting), discharge system. Discharge is also necessary before servicing any of the system components of air conditioning;
- When working near the air-conditioning system, wear safety glasses;
- After contact with the refrigerant to the skin or eyes, do not rub the affected area. Rinse immediately with cold water for at least 15 minutes. Call a doctor or hospital. Self-medication is not permitted;
- The new refrigerant cylinder is stored under pressure. Keep the bottle at a temperature no higher than 50 ?� C. Take measures to avoid the fall of the balloon from a height or other situations that could cause damage;
- Work should be done in a well-ventilated area - the refrigerant has a high volatility and its vapor accumulation can lead difficulty breathing;
- Refrigerant gas is heavier than air and relatively quickly should gather below, for example, under the car;
- Clean the condenser or evaporator using steam is not allowed - only use cold water or compressed air.
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