AUX air conditioner service manual
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analyze this phenomenon, we shall check whether air flow of indoor unit is sufficient. If it is in normal
condition, check whether there’s secondary flow restriction; judge the fault by analyze phenomena
carefully.
Case 4: Filter of outdoor unit was blocked by dirt
Unit Model：ASW-H18A4
Phenomena: air conditioner can’t cool and start & stop frequently
Cause Analysis: air conditioner failed to cool, outdoor unit started and stopped frequently, indoor unit
could be started by remote controller and run normally, but outdoor unit started and stopped every
three minutes, and air was not cool in the three minutes, so we presumed that refrigerating system
couldn’t work well; check low pressure with pressure meter: balanced pressure was 1.1MPa when air
conditioner was turned off, and pressure dropped to 0.1MPa when air conditioner was turned off and
returned to balanced pressure when it was turned off again. When outdoor unit run, frost could be
found from filter to capillary to high pressure tube, so the air conditioner was blocked by dirt.
Solution: replaced filter
Experience Conclusion: If outdoor unit starts up frequently, we should find out it is resulted by faults
in circuit or in cooling system. Generally, following symptoms will occur if filter is blocked: capillary
outlet and sometimes evaporator are frosted; low pressure is lower than normal, high pressure is
slightly lower than normal value; when air conditioner is turned out, balanced pressure closes to the
saturated pressure in ambient temperature; compressor discharge temperature and shell temperature
rise. If current is higher than normal value and air conditioner starts and stops frequently, fault may
not be in the compressor. We should consider symptoms comprehensively. Generally, when we fix an
air conditioner, we should check current and maintenance pressure, if current is relative large and
pressure is a relative low, system is blocked, and so we should check filter and capillary firstly.
Case 5 Leakage of connection line of evaporator
Unit Model：ASW-H09A4/H
Phenomena: couldn’t cool
Cause Analysis: according to the client, air conditioner can’t cool. We checked indoor and outdoor
units, both run properly, so circuit is in good condition; we checked running pressure of outdoor unit
was minus and there’s no refrigerant leaking from line joints, there’s no leakage on indoor evaporator
and outdoor unit; we disassembled the indoor unit and found that there’s a crack on the protection
spring of evaporator junction.
Solution: welded the line again, vacuums the system and added refrigerant, and air conditioner
functions proper since then.
Experience Conclusion: It is very difficult to find out leakage sources, we shall pay particular
attention to connection tube of evaporator.
Case 6 flare mouth of connection tube is broken
Unit Model：ASW-H09A4/HY
Phenomena：Poor cooling and heating efficiency
Cause Analysis: turned on the air conditioner and pushed on cooling mode, indoor unit produced wind
properly, two units were very clean, but temperature different of air inlet and outlet is very low; air
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