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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2. Maintenance
If the problem is much more serious, contact your local Midea or your local representative for assistance.
Cleaning Heat Exchangers
Check t
he chiller tightness and whether there’s leak of heat exchange tubes. It is necessary to do
nondestructive inspection for the principal weld (longitudinal and circumferential weld of
evaporator/condenser barrel) of pressure vessel. Inspect and clean cooler tubes at the end of the first
operating season. Tube condition in the exchanger will determine the scheduled frequency for cleaning,
and will indicate whether water treatment is adequate in the water circuit. Too much scale will cause big
loss of capacity and efficiency.
Refer to the following pressure-temperature curve for condition in heat exchangers:
High pressure-cooling water temperature (high pressure beyond 0.6~1.2MPa is abnormal)
Fig.26 High pressure at full load (standard unit)
Low pressure-chilled water temperature (low pressure beyond 0.14~0.37MPa is abnormal)
Fig.27 Low pressure at full load (standard unit)
Cleaning work must be done when too much scale found. Physical and chemical cleaning can be
chosen according to the device you have. Generally, chemical cleaning is much easier to carry out.
Methods are as below and the services of a qualified water treatment specialist should be obtained to
develop and monitor a treatment program.