SSANGYONG Rexton Y200, Руководство пользователя

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GENERAL HVAC SYSTEM 7B-3
SSANGYONG Y200
REPAIR INSTRUCTIONS
Air Conditioning
Vehicle air conditioning is the cooling (refrigerant),
heating and ventilation of the air in the passenger
compartment. Refrigerant is accomplished by making
practical use of the three laws of nature. These laws of
nature and their practical application are as follows:
•
Heat transfer
•
Latent heat of vaporization
•
Effect of pressure on boiling or condensation
Heat Transfer
The principle of heat transfer are that the heat always
flow from hot to cold, the rate of heat transfer will
increase as the difference in temperature between two
objects increases, and the mass of an object remains
the same regardless of its heat contents.
Latent Heat of Vaporization
Everything in the world is composed of matter and the
matter exists in one of following states;
•
Solid
•
Liquid
•
Vapor
When a liquid boils, it changes to vapor and absorbs
heat without raising the temperature of the resulting
vapor.
When the vapor condenses, it changes back to a liquid
and gives off heat without lowing the temperature of
the resulting liquid.
Effect of Pressure on Boiling or Condensing
When the pressure on the liquid or vapor changes, the
boiling point changes. Increasing the pressure
increases the boiling point, while the boiling point
decreased by decreasing the pressure on the liquid
or vapor.
Another effect of the compression is an increase in
temperature even through heat has not been added.
For example, if you compress the refrigerant R-134a
from 206kPa (30 psi) to 1206kPa (175 psi) the
temperature of vapor will increase from 0 ° C (32 ° F) to
54 ° C (130 ° F) and boiling point increase. Condensing
point also will increase.
Testing the refrigerant system
1. Check the outer surfaces of the radiator and the
condenser cores to be sure that the airflow is not
blocked by dirt leaves or other foreign material.
Check between the condenser and the radiator as
well as all outer surfaces.
2. Check for any restrictions or kinks inthe condenser
core, the hoses and the pipes.
3. Check the operation of the blower fan.
4. Check all the air ducts for leaks or restrictions. Low
airflow rate may indicate a restricted evaporator
core.
5. Check for slippage of the compressor clutch.
6. Check the drive belt tension.
Handling O-Ring
1. Even though O-rings may look identical, it is
extremely important that only recommended service
replacement air conditioning O-rings be used, or
excessive leakage of the refrigerant may occur.
2. Always O-ring and installation area should be kept
clean. Any foreign material and dust may result in
excessive refrigerant leakage.
3. Before installation, verify that both O-ring and
fittings have not been nicked or deformed.
Deformed or nicked parts must be replaced.
4. Failure to use the proper service replacement parts
and procedures may result in excessive refrigerant
leakage.
Handling Refrigerant
1. Always work in a well-ventilated area.
2. If you have difficulty breathing, seek medical
attention immediately. If refrigerant comes in
contact with any part of your body, flush the
exposed area with water. If a rush or pain develops
seek medical attention.
Handling of Refrigerant Lines and Fittings
1. Using too low or too high a torque when tightening
a fitting can result in loose joints or deformed joint
parts.
2. Back up the opposing fitting to prevent the distortion
of the connecting lines or the components. Back
up both the swaged fitting on the flexible hose
connections and the coupling to which it is attached
two wrenches to prevent turning the fitting and
damaging the ground seat.
Maintaining Chemical Stability In the
Refrigeration System
The efficient operation and life of the air conditioning
system is dependent upon the chemical stability of
the refrigeration system.
When foreign materials, such as dirt, air or moisture,
contaminate the refrigeration system, they will change
the stability of the refrigeration and the polyalkalene
glycol (PAG) compressor oil. They will also affect the
pressure-temperature relationship, reduce efficient
operation and can possibly cause interior corrosion and
abnormal wear of moving parts.