Midea LSBLG255/MZ, Техническое и сервисное руководство

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MCAC-CTSM-2014-03 DX type water-cooled screw chiller (PCB Control)
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In case doing cleaning after the unit stops, the capacity of flume of cooling tower can be 1/2 or 1/3 of
rated value; if doing cleaning as the unit is running, the capacity should achieve rated value.
Precautions on usage of detergent
When doing cleaning, please wear rubber gloves and do not expose your skin or your clothes to the
detergent. In case touching the detergent, please wash it with clean water.
The container for detergent should be made of plastic or glass rather than lead. The used detergent
should be neutralized with lime or soda before draining
Detergent is harmful to human; please keep it away from children.
Turn on the unit after cleaning to ensure it is clean. If necessary, please do cleaning again.
c) Precautions of chemical cleaning

When doing cleaning please wear rubber gloves and do not expose your skin or your clothes to the
detergent. In case of touching the detergent, please wash with clean water immediately.

The container for detergent should be made of plastic or glass rather than lead.

The used detergent should be neutralized with lime or soda before draining.

Detergent is harmful to human body; please keep it away from children.

Turn on the unit to check the effect after cleaning work done. If necessary, please do cleaning again.
Water Treatment
Before every start-up, clean and flush the cooling water circuit. Make sure tower blow-down or bleed-off
is operating. It should be recognized that atmospheric air contains many contaminants that increase the
need for proper water treatment. The use of untreated water can result in corrosion, erosion, sliming,
scaling or algae formation. Midea assumes no responsibility for the results of untreated or improperly
treated water.
Refrigerant Circuit
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Leak testing
Units are factory-charged with refrigerant R-22 (Refer to the Physical Data tables supplied in the IOM
manual book). Leak test must be done under sufficient pressure. This can be done by charging enough
refrigerant into the system to build the pressure up to approximately 70 kPa and adding sufficient dry
nitrogen to bring the pressure up to a maximum of 850 kPa. Leak test with an electronic leak detector.
Water flow through the vessels must be maintained anytime refrigerant is added or removed from the
system. If any leaks are found in welded or brazed joints, or it is necessary to replace a gasket, relieve
the test pressure in the system before proceeding. Brazing is required for copper joints. After leaks are
repaired, system must be evacuated and dehydrated.
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Evacuation
After it has been determined that there are no refrigerant leaks, the system must be evacuated using a
vacuum pump with a capacity that will reduce the vacuum to at least 130Pa (=1mmHg). A mercury
manometer, or an electronic or other type of micron gauge, must be connected at the farthest point from
the vacuum pump. For readings below 130Pa, an electronic or other micron gauge must be used. The