Midea MGRH10A-PA1Z, Manual

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Aqua Mini Full DC Inverter Unitary Chiller 50Hz
44
the chilled water system shuts down during summer. The lower temperature in a heating system is often the
ambient temperature at fill conditions(for example, 50
o
F or 10
℃
).
h). Water quality control
When industrial water is used as chilled water, little furring may occur; however, well water or river water,
used as chilled water, may cause much sediment, such as furring, sand, and so on. Therefore, well water or
river water must be filtered and softened in softening water equipment before flowing into chilled water
system. If sand and clay settle in the evaporator, circulation of
chilled water may be blocked, and thus leading to freezing accidents; if hardness of chilled water is too high,
furring may occur easily, and the devices may be corroded. Therefore, the quality of chilled water should be
analyzed before being used, such as PH value, conductivity, concentration of chloride ion, concentration of
sulfide ion, and so on.
PH 6-8
Total hardness less than 50 ppm
Electrical conductivity less than 200 mV/cm (25
°
C)
Sulfide ion none
Chlorine ions less than 50 ppm
Ammonia ions none
Sulfate ion less than 50 ppm
Silicon less than 30 ppm
Total iron less than 0.3 ppm
Sodium ion No requirement
Calcium ion less than 50 ppm
Filling the installation
- Before filling, check that the installation drain cock is closed.
- Open all installation and terminal air vents.
- Open the gate valves.
- Begin filling, slowly opening the water filling cock outside the unit.
- When water begins to leak out of the terminal air vent valves, close them and continue filling until the
pressure gauge indicates a pressure of 1.5 bars.
Emptying the installation
- Before emptying, place the mains switch in the
“
off
”
position.
- Make sure the installation fill/top-up water cock is closed.
- Open the drain cock outside the unit and all the installation and terminal air vent valves.