23
When the power cord is parallel to the signal wire, make
sure that they are enclosed in respective conduits and
are kept a reasonable wire spacing. (Distance between
the power cord and signal wire: 300mm if below 10A,
and 500mm if below 50A)
NOTE
In the case of multiple units connection, the HMI of
65KW and 110KW can be parralled with in the same
system.
CAUTION
8.5 Water system installation
8.5.1 Basic requirements of connection of
chilled water pipes
•
After the unit is in place, chilled water pipes can be
laid.
•
The relevant installation regulations should be
abided with when conducting connection of water
pipes.
•
The pipelines should be free of any impurity, and all
chilled water pipes must conform to local rules and
regulations of pipeline engineering.
CAUTION
Connection requirements of chilled water pipes
a) All chilled water pipelines should be thoroughly flushed, to
be free of any impurity, before the unit is operated. Any impurity
should not be flushed to or into the heat exchanger.
b) Water must enter the heat exchanger through the inlet;
otherwise the performance of the unit will decline.
c) The pump installed in the water pipeline system should be
equipped with starter. The pump will directly press water into the
heat exchanger of the water system.
e) The pipes and their ports must be independently supported
but should not be supported on the unit.
f) The pipes and their ports of the heat exchanger should be
easy to disassemble for operation and cleaning, as well as
inspection of port pipes of the evaporator.
g) The evaporator should be provided with a filter with more
than 40 meshes per inch at site. The filter should be installed
near to the inlet port as much as possible, and be under heat
preservation.
h) The by-pass pipes and by-pass valves 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) The common outlet pipelines of combined units should be
provided with mixing water temperature sensor.
•
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.
•
When the ambient temperature is lower than 2°C,
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.
WARNING
Summary of Contents for KEM-HT-75
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