Chery T21 2014 Service Manual page 1390

31 - AIR CONDITIONING
4. Listen to the operation sound of A/C compressor assembly while it is operating at maximum and minimum
displacement positions.
5. Using an engine sound scope or a long screwdriver with handle, hold the A/C compressor assembly near
your ear for detecting, in order to locate the noise source easier.
6. To duplicate a high temperature condition (high pressure), air is limited to flow through the A/C condenser.
Install a manifold pressure gauge set to ensure that the discharge pressure is lower than 2550 kPa.
7. Check the condition of compressor assembly belt.
8. Check the compressor assembly hub, pulley and bearing assembly. Make sure that the hub and pulley are
aligned correctly, and the pulley bearing is securely installed to the A/C compressor assembly.
9. Check if the refrigerant line routes incorrectly, is damaged or has an interference that could result in an
abnormal noise. Also, check the refrigerant line for twist or bend, otherwise the refrigerant will be limited to
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flow, which will cause a noise.
10.Loosen all the compressor assembly tightening bolts and retighten them.
11. If noise occurs when the liquid refrigerant in A/C suction pipe is under a slugging condition, replace the
condenser and check the refrigerant oil level and the charging condition for refrigerant.
12.If the slugging condition still exists after replacing the condenser, replace the A/C compressor assembly.
WARNING
 DO NOT race engine when vacuum pump operates or vacuum exists in the A/C system. Failure to do so
may result in a serious damage to the A/C compressor assembly.
Refrigerant Leakage Inspection
WARNING
 DO NOT perform pressure test or leakage test to R134a service device or vehicle A/C system with
compressed air. Air mixture and R134a is inflammable at high pressure. These mixtures have potential
danger, and it may cause a fire or explosion, resulting in vehicle damage, personal injury or death.
 Avoid inhaling vapor or moisture from the A/C refrigerant and refrigerant oil.
 Only use technical service device to discharge the R134a system. If system is discharged unexpectedly,
ventilate the work place before servicing.
CAUTION
 If the A/C refrigerant filling amount is empty or low, the A/C system may have leak. Check all A/C lines,
joints and parts for remaining oil. The remaining oil is the indication mark of A/C system leaking position.
Check refrigerant for leakage
1. After recharging refrigerant, use the gas leak detector to check the refrigerant gas for leakage.
2. Perform operations under the following conditions:
 Stop the engine.
 Ensure the ventilation is well (the gas leak detector may react to volatile gases which are not from
refrigerant, such as gasoline vapor or exhaust gas).
 Repeat the test for 2 or 3 times.
 Make sure that there is some refrigerant remaining in the refrigerant system.
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Chery Automobile Co., Ltd.