In a chilled water system, the higher temperature T2 is the highest anticipated ambient temperature when
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℉ or 10℃).
14.7 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.
Filling the installation
Before filling, check that the installations 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.
PH
Total hardness
Electrical conductivity
Sulfide ion
Chlorine ions
Ammonia ions
Sulfate ion
Silicon
Total iron
Sodium ion
Calcium ion
6~8
less than 50 ppm
less than 200 mV/cm (25℃)
none
less than 50 ppm
none
less than 50 ppm
less than 30 ppm
less than 0.3 ppm
No requirement
less than 50 ppm
V.2
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