Kaysun KEM-30 DNH3, Техническое руководство

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h. The by-pass pipes and by-pass valves as shown in the figure of “ Connection drawing of pipeline
system” must be mounted for the heat exchanger, to facilitate cleaning of the outside system of water
passage before the unit is adjusted. During maintenance, the water passage of the heat exchanger can be
cut off without disturbing other heat exchangers.
i. The flexible ports should be adopted between the interface of the heat exchanger and on-site pipeline, to
reduce transfer of vibration to the building.
j. To facilitate maintenance, the inlet and outlet pipes should be provided with thermometer or manometer.
The unit is not equipped with pressure and temperature instruments, so they need to be purchased by the
user.
k. All low positions of the water system should be provided with drainage ports, to drain water in the
evaporator and the system completely; and all high positions should be supplied with discharge valves, to
facilitate expelling air from the pipeline. The discharge valves and drainage ports should not be under heat
preservation, to facilitate maintenance.
l. All possible water pipes in the system to be chilled should be under heat preservation, including inlet pipes
and flanges of the heat exchanger.
m. The outdoor chilled water pipelines should be wrapped with an auxiliary heating belt for heat preservation,
and the material of the auxiliary heat belt should be PE, EDPM, etc., with thickness of 20mm, to prevent the
pipelines from freezing and thus cracking under low temperature. The power supply of the heating belt
should be equipped with an independent fuse.
n. When the ambient temperature is lower than 2 , and the unit will be not used for a long time, water inside
the unit should be drained. If the unit is not drained in winter, its power supply should not be cut off, and the
fan coils in the water system must be provided with three-way valves, to ensure smooth circulation of the
water system when the anti-freezing pump is started up in winter.
o. The common outlet pipelines of combined units should be provided with mixing water temperature sensor.
Warning:
● For the water pipeline network including filters and heat exchangers, dreg or dirt may seriously damages
the heat exchangers and water pipes.
● The installation persons or the users must ensure the quality of chilled water, and de-icing salt mixtures
and air should be excluded from the water system, since they may oxidize and corrode steel parts inside the
heat exchanger.
11.2.2 Water Quality
-, -
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.
Applicable standard of water quality for the unit
PH
value Total
hardness Conductivity Sulfide
ion Chloride
ion Ammonia
ion Sulfate
ion Silicon Iron
content Sodium ion Calcium
ion
7
8.5
<50ppm <20μV/cm(25 ℃ ) No <50ppm No <50ppm <30ppm <0.3ppm No
requirement
<50ppm
Performance adjustment factors
The antifreeze must be required according to anyone condition as following:
1. The outlet water temperature is below 5 ;
2. The ambient temperature is below 0
;
3. Don’t start up the unit for a long time.