5-33
January 24, 2017
Fault Diagnosis and Judgment
CLG835H
Overhauling method
Items
Fault conditions
Cause
Troubleshooting meth-
ods
1
Air bubbles persistently exist in sight glass, com-
pressor air intake hose joint is not cold enough
and even warm, the upper end and lower end of
reservoir do not have temperature difference, and
temperature is higher than or equal to ambient
temperature
Refrigerant leakage.
Insufficient refrigerant fill-
ing amount.
Check and repair leakage
parts, and refill refrigerant.
Refer to A/C Refrigerant Fill-
ing Method
2
Compare the pressures of air conditioning system
operating at high and low pressures with normal
pressures (see table attached hereinafter)
Pres
sur
e
of
low pr
essure
sid
e
a
nd hig
h pressure
si
de are bo
th
lo
w
1. Normally refrigerate for several min-
utes, stop refrigerating for several
minutes, and normally refrigerate for
several minutes…repeat like this.
2. Compressor is operating continu-
ously.
3. The pressure at the beginning of
refrigeration is normal, and pressures
at low pressure side and high pres-
sure side when refrigeration stops
are obviously low.
There is too much water
in refrigerating system to
cause ice blockage in
expansion valve (orifice is
frozen due to water accu-
mulation to block orifice)
Replace reservoir, vacuum
pumping for more than 1 h,
and fill refrigerant once again
as specified in Removal and
Installation of A/C Compo-
nents
1. Touch compressor air intake hose
joint (thick joint) by hand to feel no
coldness.
2. There are no big differences in tem-
perature of the high temperature
zone and the low temperature zone
of a condenser.
3. The temperature of each part of res-
ervoir is basically the same to that of
condenser outlet and close to ambi-
ent temperature.
The interior part of refrig-
erating system is very
dirty, and the expansion
valve orifice is blocked by
dirt
1. Switch on refrigeration for
about 1 minute and switch
off refrigeration for about
3~5 minutes with doors
and windows open under
high engine speed (engine
can be at idle speed but air
volume shall be in highest
position), then step on
accelerator to refrigerate
for about 1 minute…repeat
like this for three times so
that contamination and
blockage may be elimi-
nated.
2. If the above methods are
ineffective, clean or
replace expansion valve; If
gray black or brown black
color appears in sight
glass, please make sure to
replace reservoir.
The expansion valve con-
trol head leaks and the
valve hole switches
smaller automatically
Replace the expansion
valve; If gray black or brown
black color appears in sight
glass, please make sure to
replace reservoir.
Summary of Contents for CLG835H
Page 2: ......
Page 4: ...Contents January 24 2017 CLG835H...
Page 6: ...1 2 General Information January 24 2017 CLG835H...
Page 38: ...1 34 Machine Inspection Table January 24 2017 CLG835H...
Page 156: ...3 2 Power Train System January 24 2017 CLG835H...
Page 214: ...3 2 Power Train System January 24 2017 CLG835H...
Page 272: ...3 60 Testing and adjustment January 24 2017 Power Train Test CLG835H...
Page 276: ...4 4 Hydraulic System January 24 2017 CLG835H...
Page 552: ...6 2 Driver s Cab System January 24 2017 CLG835H...
Page 608: ...7 2 Structure January 24 2017 CLG835H...
Page 662: ...8 4 Electrical System January 24 2017 CLG835H...
Page 677: ...8 19 January 24 2017 Structure Function Principle CLG835H Power System P18E00014...
