7.1.7 Remove the evaporator assembly.
7.1.8. Use a wrench to disassemble the expansion valve.
7.2. Installation of the Evaporator Assembly
The installation steps are reverse to those for removal.
After the installation, the system should be evacuated, proper
pressure should be maintained and anti-freeze agent should be filled
to check for any leakage. Check if the radiator is blocked and
pressure air can be used to get it through if it is.
III. Trouble Shooting
Types of pressure deviation Possible causes Method for troubleshooting
1. The pressure at the high pressure
side remains unchanged or just
slightly rises (compared with the
value when the engine stalls); the
pressure at the low pressure side is
within or under the range as
shown; the air conditioner is under
refrigeration.
2. The pressure at the high pressure
side is normal; the pressure at the
low pressure side is within the
range as shown; the air conditioner
is under refrigeration.
Lack of refrigerant or the expansion
valve fails
Evacuate the refrigerant
●If the volume of the refrigerant is normal
1. Replace the expansion valve
2. Refill the refrigerant to the system
3. Test the pressure again
●If the volume of the refrigerant is short
1. Check if there is leaking, if there is
fix it
2. Refill the refrigerant to the system
3. Test the pressure again
The pressure at the high pressure side is
higher than the specified value; the
pressure at the low pressure side falls
rapidly to within or under the range as
shown; the air conditioner is under
refrigeration.
The blockage or throttling occur
somewhere in the refrigerant
pipelines
The expansion valve fails
Touch the pipelines to feel the temperature
change
●If there exists temperature differences on
several parts of a certain component
1. Dredge the pipe with compressed air
and nitrogen and replace the expansion
valve.
2. Replace the blocked parts.
●If no trouble found:
1. Dredge the pipelines with compressed air
and nitrogen
2. Test the pressure again.
Initially, the pressures at the high and
low pressure sides are normal, but after a
period of time, the pressure at the high
pressure side is higher than the specified
value and the pressure at the low pressure
side is within or under the range as
shown; the air conditioner is under
refrigeration.
The expansion valve fails
There exists vapor in the refrigerant
pipelines
Check for dirt or rust in the expansion valve
and replace it when necessary
●Dredge the pipelines with compressed air
and nitrogen
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