AUX E Series, Руководство по обслуживанию

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AUX air conditioner service manual
199
Generally, system shall be purged under a pressure of 0.6MPa which can be pressurized with
refrigerating compressor, nitrogen bottle or air compressor (compressed air can’t be used in Freon
system). System shall be blown in sections, with dirt outlet set on the lowest point of each section.
Each dirt outlet shall be plugged up with cork (tied with steel wire). When pressure reaches 0.6MPa,
stop pressuring, and draw out cork, and discharge the dirt in this system by using high-velocity air
flow.
Hang a piece of white cloth on the dirt outlet to check if system has been cleaned completely. If white
cloth is clean, dirt in the system has been evacuated with gas, blowing can be stopped; if there’s some
stain on the white cloth, blowing shall continue.
Section three Troubleshooting for four-way valve and compressor
1. Troubleshooting method for four-way valve of heat pump air conditioner
⑴
Troubleshooting of four-way valve
①
Air conditioner can make cooling air but can’t make any heating air
Check service power voltage of electromagnetic loop by using millimeter; when unit is turned off,
measure the resistance of loop which normally shall be around 1400
Ω
. Switch on the air conditioner
and try to hear sound of magnetic operation so as to judge if control valve works well; check high
pressure with pressure meter, if it is very low, so we can judge that slide of reverse valve can’t be
moved and can’t change the flow direction of refrigerant when the unit made in heating operation.
②
Fail to function in both cooling and heating operations
There’re two possibilities: discharge capacity of compressor is not sufficient or four-way valve itself is
of poor quality. Firstly, judge the quality and discharge capacity of compressor: remove four-way
valve, connect refrigerating system and run it. If the system can cool the room in a relative high
efficiency, the compressor is of good quality, and so it’s the four-way valve that can’t work well and
cause leakage of four copper tubes, high and low pressure tubes are short circuited.
③
Air conditioner is set in cooling operation but functions in heating operation.
Four-way valve is blocked inside and can’t reverse the direction;
④
Cooling normally after it is started and run 2~3 times
According to the work principle of four-way valve, we can judge that valve core can’t seal tightly, and
air leaks in 4 directions under high pressure, so pressure is not large enough to seal capillary control
valve, and slid of reverse valve can’t function successfully in one time.
⑵
Steps to change four-way valve
If it is clear that four-way valve is broken, it shall be replaced with the new one of same size and type,
and in the following way:
①、
Remove the old four-way valve from air conditioner
②、
Install new four-way valve and remove electromagnetic loop. 4 copper tube nozzles shall be
positioned in their original directions and angles, reverse valve shall be positioned horizontally.