AUX E Series, Service Manual

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AUX air conditioner service manual
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Experience Conclusion: valve is too tight, so system is obstructed and then frosted. When refrigerating
efficiency of new unit was unsatisfactory, do not add refrigerant without careful consideration.
Case 15 Air conditioner was blocked by dirt
Unit Model
：
ASW-H41A5/A
Phenomena
：
Poor cooling efficiency, wind velocity didn’t change obviously
Cause Analysis: totally 5 cabinet air conditioners were used in a workshop of a Garment Company,
which occupied an area of 350m
2
. According to the client, air conditioners were repaired many times
in this year, but they still failed to work properly. We checked the air conditioner, voltage was 380v,
and current was 9A, low pressure was 5kg, which was normal; however, temperature of wind outlet
was relatively high. Based on the forgoing data, we presumed that faults were caused by weak wind.
The main factors may be: 1.fault in fan 2. Fault in capacitor of fan 3. Filter and evaporator were dirty;
4. Fault in control panel. Checked the system, we found that wind was weak, fan and capacitor were in
good condition; adjusted wind velocity (high, intermediate and low), three levels of fan relay closed
with obvious sound, but wind velocity failed to change distinctively. So we judged that fault was
caused by dirt-block of evaporator. Disassembled evaporator and found that there was a great deal of
fiber in it, and it was frosted.
Solution: clean indoor evaporator, wind volume became normal, air conditioners could produce cool
properly
Experience Conclusion: in some special places, for example, garment factories, hair salon, cotton mill
and other places with more dirt as well as public. In such case, poor cooling efficiency was generally
caused by discharge fault, because the system was blocked by dirt. Firstly we should check filter and
evaporator to find out if they were dirty. To fix such kind of fault, we should check surrounding
factors and then checked faults in air conditioners; checked wind volume of indoor and outdoor units,
if ambient temperature is too high; if the two units’ heat exchange properly, finally checked the system
itself.
Case 16 Folding of Connection pipe
Unit Model
：
ASW-18A4/TA
Phenomenon
：
Poor cooling efficiency
Cause Analysis: Abnormal sound could be heard in indoor unit. When air conditioner runs for three
minutes and under ventilation mode, no abnormal sound was heard, but when compressor was turned
on, indoor evaporator produced abnormal loud sound of cold flow. Checked the system and found that
outlet tube of indoor evaporator and copper tube of condenser were bent on the junction between the
two tubes.
Solution: replace connection tube
Experience Conclusion: in such case, abnormal flow sound is produced by unsmooth flowing of
refrigerant, and only when we check the system carefully can we find where the line is bent, which is
caused by unprofessional performance of maintenance workers.
Case 17 Bending of connection line
Unit Model
：
ASF-H24B4