29
Error
Error
Recommendation
Recommendation
Fig.8-26 Design of the store tank
Fig. 8-27-1
Fig. 8-27-2
8.5.4 Minimum chilled water flow
8.5.7 Selection and installation of the pump
1) Select the pump
a) Select the water-flow of the pump
The rated water-flow must no less than the unit rated
water-flow; in terms of multi-connect the units, that water-
flow must no less than total units’ rated water-flow.
b) Select the left of the pump.
H=h1+h2+h3+h4
H: The lift of the pump.
h1: Main unit water resistance.
h2: Pump water resistance.
h3: Water resistance of the longest water-loop distance,
includes:
pipe resistance, different valve’s resistance, flexible pipe
resistance, pipe elbow and three-way resistance, two-
way resistance or three-way resistance, as well as filter
resistance.
H4: the longest terminal resistance.
2) Installation the pump
a) The pump should be installed at the water inlet pipe,
both of which sides must mount the soft connectors for
vibration-proof.
b) The backup pump for the system (recommended).
c) Units must with a main unit controls (Please see Fig. 8-18
for the controls wiring diagram).
8.5.8 Water quality
1) 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.
8.5.5 Maximum chilled water flow
8.5.6 Minimum and Maximum water flow
The minimum chilled water flow is shown in the table 8-8
If the system flow is less than the minimum unit flow
rate, the evaporator flow can be recirculated, as shown
in the diagram.
For minimum chilled water flow rate
The maximum chilled water flow is limited by the
permitted pressure drop in the evaporator. It is provided
in the table 8-8
If the system flow is more than the maximum unit flow
rate, bypass the evaporator as shown in the diagram to
obtain a lower evaporator flow rate.
Table 8-6
Recirculation
Recirculation
UNIT
UNIT
Item
Model
Waterflow rate(m
3
/h)
Minimum
Maximum
KEM-30 DRS4.1
3.8
6.4
KEM-60 DRS4.1
8.0
13.0
KEM-90 DRS5
10.2
18.0
Summary of Contents for KEM-90 DRS5
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