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2).The evaporator is frosting;
Frosting on the sedan A/C evaporator can be treated according to
the following aspects:
1).The thermo expansion valve is in abnormal operation: replace the
thermo expansion valve;
2).The evaporator is deficiency in draught: find out the reason and
eliminate it;
3). Thermo sensitive resistance of the temperature controller is in
incorrect mounting position, so it is incapable of sensing the surface
temperature of the surface temperature. Install the thermo sensitive
resistance per correct position;
4). Thermo sensitive resistance of the temperature controller is out
of service so that the compressor can not stop; uninterrupted
refrigeration will lower down the surface temperature of the
evaporator. When the temperature is below 0℃, water vapor in the
air flowing through the evaporator will be frosted on external surface
of the evaporator: replace the thermo sensitive resistance;
5).Design temperature of the temperature controller thermostat is
over low that causes surface temperature of the evaporator below
0℃ to frost: replace the thermostat;
3)The evaporator assembly is
blocked
3) The ice block is caused by the moisture in the system and the
dirty block is caused by the impurities such as the aluminium chips in
the system; result of the ice block is that the evaporator is not cool
sometimes, while the result of the dirty block is that the evaporator is
not cool or is inadequate in the cooling volume: eliminate the
moisture or the impurities.
4)The thermo expansion valve
is blocked or leaked;
4).Constant malfunction of the thermo expansion valve: power head
(gas phase head) of the thermo expansion valve is leaked that
causes inadequate opening or incapable of being opened of the
thermo expansion valve, thus the evaporator is not cool or is
inadequate in cooling volume: replace the thermo expansion valve.
1).There has dirt on the
condenser flat pipe and the
heat emission fin, which will
reduce the heat transfer
capability and increase the high
pressure in the refrigeration
system;
Clean out dirt and impurities on the flat pipe and the heat emission
fin;
2).There is impurity blockage
on the condenser heat
emission fin;
Purge them with compressed air;
3).The condenser heat
emission fin is of flexural
deformation;
Calibrate it with the nipper pliers and replace the condenser if it is
severe;
Condenser
4).The condenser is leaking;
Replace the condenser
1)Dry reservoir assembly is
blocked;
The block reason is the pulverizing of the drier as well as too many
impurities in the system; the phenomena is that the high pressure is
increased and there has apparent temperature difference between
inlet and outlet of the dry reservoir assembly: replace the dry
reservoir;
Dry reservoir
2)Filter screen inside the dry
reservoir assembly is damaged;
Thermo expansion valve maybe blocked so that the a/c will not
refrigerate: replace the dry reservoir and check the thermo
expansion valve;