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السبت، 23 أغسطس 2014

REMOVAL AND INSTALLATION INSTRUCTIONS AUTO AIR CONDITIONER

REMOVAL AND INSTALLATION
INSTRUCTIONS
AUTO AIR CONDITIONER





Air conditioning system:



Prior to removal and/or installation of the spare part it must be verified that connections, fixings and other installation-relevant properties are identical.

When replacing components, always use new O-rings suitable for the refrigerant.

The compressor oil has a strong hygroscopic effect. Thus, the system must be kept closed if possible and/or the oil is to be filled shortly prior to closing the refrigerant circuit only.

Prior to the installation, O-rings and seals are to be greased with refrigerant oil or special lubricants in order to facilitate installation. No other greases or silicone spray may be used as this results in immediate contamination of the new refrigerant.

For every opening of the refrigerant circuit the dryer must be replaced due to its strong hygroscopic effect. If dryer or accumulator are not replaced on a regular base, the filter pad may decompose and silicate particles may be distributed in the entire system and cause severe damage.

The system connections should never remain open for an extended period of time, but should be immediately closed using caps or plugs. Otherwise, liquid would be entered together
with air into the system.
In order to avoid damage to connection pipes and/or components, always use two wrenches when loosening and fastening the connections.

When routing tubes and cables make sure that no damage is possible caused by vehicles edges or other moving components.

When replacing a component of the air conditioning system, the correct oil quantity in the system is to be ensured. Oil must be refilled or drained as needed.

Prior to refilling the system, it must be checked for leaktightness. Next, the system is to be sufficiently evacuated (approx. 30 minutes) in order to ensure that all humidity is removed from the system.















After filling the refrigerant quantity specified by the vehicle manufacturer, the system is to be checker for proper function and leak-tightness (electronic leak indicator). At the same time, the high and low pressure values must be observed using pressure manometers and compared with the specified values. Compare the outflow temperature on the centre vent with the values specified by the manufacturer.

After the service connections are fitted with protective caps, the maintenance due date is to be indicated on an adhesive service label on the front cross member.

Information regarding the installation of air conditioning system compressors:

Make sure that all contaminations and foreign substances are removed from the refrigerant circuit. For this purpose, the system is to be flushed prior to installing the new compressor. Depending on the level of contamination, refrigerant R134a or a special flushing solution is suitable for flushing. Compressors, dryers (accumulators), expansion valves and/or orifice tubes cannot be flushed. As it must always be assumed and cannot be
ruled out that the system is contaminated (abrasion, swarf) when a compressor is defective, the system must always be flushed when this component is replaced. Make sure that no flushing solution residues remain in the system. Dry the refrigeration circuit using nitrogen as needed.

Replace the filter dryer or accumulator and the expansion valve or orifice tube.









As one and the same compressor can potentially be used for different vehicles or systems, the oil filling quantity and viscosity must be checked and/or corrected according to the manufacturer's specifications before installing the compressor. All the oil must be siphoned off and collected. The compressor must then be newly filled with the entire oil quantity specified by the vehicle manufacturer (system oil quantity).The compressor must be spun 10 x by hand before being installed to ensure the oil is distributed evenly. When installing the drive belt it must be ensured that it is aligned. Some compressors are designed for so-called "multiple applications". This means that they can be installed in different vehicles. Except the number of grooves on the magnetic clutch, there is 100% agreement with the "old part".
After compressor installation and new filling of the refrigerant circuit, the engine should first be started and operated for several minutes at idling speed.

Further specifications (instruction leaflets, manufacturer's specifications, run-in specifications) are to be separately observed.
                                                 kandi younes
.

REPAIR AND SERVICE AUTO AIR CONDITIONER

REPAIR AND SERVICE
 AUTO AIR CONDITIONER







REPAIR AND SERVICE:

Safety information/handling of refrigerant:
 
*    Always wear safety glasses and safety gloves!
Under normal atmospheric pressure and at ambient temperatures liquid refrigerant evaporates so suddenly that contact with skin or eyes may cause frost damage to the tissue (risk of blinding).

*    In the case of contact, rinse the affected locations with plenty of cold water. Do not rub. Immediately seek medical attention!

*    When working on the refrigerant circuit the work-place must be well ventilated. Inhalation of high concentrations of gaseous refrigerant causes dizziness and danger of suffocation. Work on the refrigerant circuit may not be performed from working pits. As gaseous refrigerant is heavier than air, it can there accumulate in high concentrations.

*    Do not smoke!

Cigarette embers can break down refrigerant into toxic substances.

*    Refrigerant must not contact open fire or hot metal. Deadly gases may be generated.

*    Never allow refrigerant to escape into the atmosphere. If the refrigerant container or the air conditioning system are opened, the content discharges under high pressure. The pressure amount depends on the temperature. The higher the temperature is, the higher is the pressure.

*    Avoid any head impact on components of the air conditioning system. After paintwork, vehicles must not be heated above 75 °C (drying furnace). Otherwise, the air conditioning system must be drained first.

*    When removing the service tubes from the vehicle, the connections must not be pointed towards your body. Refrigerant residues may leak.
*    When cleaning the vehicle, the steam-jet cleaner must not be directly pointed onto parts of the air conditioning system.
*    Never change the factory setting of the adjusting screw on the expansion valve.
                                 
                                                             kandi younes

الأربعاء، 13 أغسطس 2014

COMPONENTS OF THE AIR CONDITIONING Troubleshooting Pressure switches and switches

COMPONENTS OF THE
AIR CONDITIONING
Troubleshooting
 Pressure switches and switches
 



Pressure switches and switches

Pressure switches are responsible for protecting the air conditioning system against damage
caused by too high or too low pressures. There are low pressure switches, high pressure switches
and trinary switches. The trinary switch comprises the high pressure switch and the low pressure
switch and an additional switch contact for the condenser fan

How they work
 
The pressure switch (pressure monitor) is normally installed on the high pressure side of the air
conditioning system. In the case that the pressure is too high (approx. 26-33 bar) it switches the
power supply to the compressor clutch off. If the pressure is reduced (approx. 5 bar), its switches
the power supply on again. If the pressure is too low (approx. 2 bar), the power supply is interrupted
as well in order to avoid compressor damage due to insufficient lubrication. The third switch
contact in the trinary switch controls the electrical condenser fan in order to ensure optimum
refrigeration condensation in the condenser
.
Effects of failure
 
A defective or failing pressure switch can manifest itself as follows:
- Insufficient cooling performance
 - Frequent switching on and off of the compressor clutch
Air conditioning system without function. There are a number of possible causes of failure:
-Contact fault at electrical connections
-Contaminations in the system
-Damage to the housing caused by vibrations or accidents

Troubleshooting
  
Test steps for fault diagnostics:

- Visual inspection
- Check connector block for correct fit
-Inspect component for damage
- Pressure measurement with the compressor switched on and the engine running
-Component test in the disassembled condition with nitrogen gas cylinder, pressure reducer


        kandi younes

الأحد، 3 أغسطس 2014

COMPONENTS OF THE AIR CONDITIONING Troubleshooting Expansion valve

COMPONENTS OF THE
AIR CONDITIONING
Troubleshooting
 Expansion valve/orifice tube

 


 
Expansion valve/orifice tube:
 



The expansion valve represents the point of separation between the high pressure and lowpressure sections in the refrigerant circuit. It is installed in upstream of the evaporator. To achieve optimum cooling capacity in the evaporator, the refrigerant flow is controlled by the expansion valve depending on the temperature. As a result, complete evaporation of the liquid refrigerant is ensured and gaseous refrigerant arrives at the compressor only. Expansion valves may differ in their design.

How they work
   
The liquid refrigerant - arriving through the filter dryer from the condenser - flows through the expansion valve and is injected into the evaporator. The evaporating refrigerant releases evaporation cold. This causes the temperature to drop. To achieve optimum cooling capacity in the evaporator, the refrigerant flow is controlled by the expansion valve depending on the temperature. At the end of the evaporator, the refrigerant is transported through the expansion valve to the compressor. If the refrigerant temperature increases at the end of the evaporator, it expands in the expansion valve. This results in an increase of the refrigerant flow (injection quantity) to the evaporator. If the refrigerant temperature lowers at the end of the evaporator, the volume in the expansion valve decreases. As a result, the expansion valve reduces the refrigerant flow to the evaporator.

Effects of failure
A defective expansion valve can manifest itself as follows:
*    Poor cooling capacity
*    Failure of the air conditioning system

There are a number of possible causes of failure:
*    Temperature problems due to overheating or icing
*    Contaminations in the system
*    Leaks at the component or the connection pipes

Troubleshooting
The following test steps should be followed in the case of a malfunction
*    Visual inspection
*    Acoustic test
*    Check connection pipes for tight and correct fit
*    Check components and connections for leak-tightness
*    Temperature measurement on the line system
*    Pressure measurement with the compressor switched on and the engine running
kandi younes