CHUNLAN -B, Руководство по обслуживанию

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Typical case analysis
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Solution: Replace with complete wire controller connecting cable of sufficient length.
Case VII: A user installed two sets of FR180/S Chunlan air duct type air conditioners. After a
period of use, it was found that cooling effect was not good, no cold air was blown out, and
air suction hose was frosting.
Analysis: One fan motor was found not operating. Measurement showed that this motor was
damaged. After replacing the motor, air delivery was still small and hose side was frosting.
Return air strainer was checked for clogging. After cleaning, air delivery was still small.
Finally, it was found that return air duct was leaking and indoor unit strainer was seriously
blocked.
Solution: Repair leakage in return air duct and remove indoor unit strainer for cleaning.
Case VIII: A user installed two sets of FR260/S Chunlan air duct type air conditioners in 2001.
Shortly afterward, it was found that E6 protection occurred on one of them. Our Jinan service
agent went on site for inspection. Measurement showed that each parameter of power supply
was normal. After re-poweron and operation for 2 hours, E6 protection occurred again. Later,
E2 and E7 protections occurred sometimes, but after re-poweron, normal operation lasted for
a period and no abnormity was found in voltage, current or pressure. Bizarre enough, after
swapping indoor/outdoor main control boards and wire controllers of two units, the same
protections occurred on the same unit.
Analysis: According to past maintenance experience, main control board manufactured before
2002 and used in humid environment can cause such wrong protections sometimes.
Solution: Replace with new indoor/outdoor main control boards.
Case IX: An installation company installed more than 10 air duct type air conditioners in
Dafeng, Jiangsu. For commissioning, when wire controller was plugged on, it was found that
wire controllers of several units displayed E5 protection and some even had no display. After
replacing with good wire controllers, the same failure occurred. This fault was not cleared
after replacing main control board.
Analysis: Bad connection on wire controller socket due to being covered by coating and paint
used for room decoration.
Solution: Use needle to remove covering material at wire controller socket and reconnect.
Case X: 9 sets of FR260/S air duct type air conditioners were installed in a ballroom. User
complained about high temperature in rooms (29
℃
) that cannot be brought down and poor
cooling and heating effect. Site inspection showed that current system and pressure were
normal. Area of application was about 150m
2
/unit. Unit type selection was correct and room
thermal insulation was good.
Analysis: (1) Poor sealing between return air duct and air delivery port diffuser. Clearance
was between 2mm and 15mm. That return air duct only returned ceiling hot air was the main
cause of te phenomena.
(2) Air delivery in each room was not even, hence poor effect.