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Installation Requirements
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can also be cut off during maintenance without affecting the normal operation of other units. Caution: Before
the cut-off, it is necessary to confirm that the corresponding unit is in shutdown state, and when it is cut-off
for a long time in the winter, the cut-off unit must drain the water completely, in order to prevent the heat
exchanger from the frost damage.
The water flow direction shall be connected according to the water inlet pipe and outlet pipe indicated on the
unit, otherwise the performance of the unit will be affected.
The connection among the pipeline, the water pump and the air-conditioner main machine must adopt flexible
connecting pipe, and the flexible connecting pipe shall not be forcibly connected. The purpose is to reduce the
transmission of vibration.
The unit itself does not have water pump, hence the water pump must be installed separately. The unit only gives
a 220V starting signal for the contactor of the control water pump, and the system’s chilled water (evaporator)
pump can be connected to the main board DO5 of the master unit (1 # module). System’s cooling water’s
(condenser) water pump can be connected to the main board DO6 of the master unit (1 # module).
In addition to the main pump, there also need to install a backup water pump, so that the water pump will not
affect the use of the unit when it fails.
The outlet of the water pump shall be installed with a check valve.
If multiple stand-alone modules share one water system, each water pump’s outlet shall also be installed with
a check valve.
Water pump’s water inlet pipe requires the users to provide a water filter which is not less than 30 meshes by
themselves, in order to ensure the reliable operation of the water pump.
The water flow switch must be installed on each module’s cooling-water and chilled-water outlet pipe. See
Chapter 2.9 for installation mode.
All water system’s lowest points shall be provided with drainage valves, so that the water in the evaporator,
condenser and system can be completely drained when not in use in winter.
All water system’s high points shall be provided with automatic exhaust valves to exhaust the air from the
pipeline.
For completely closed water system (without open expansion tank), the automatic water supply valve can
automatically replenish the water supply system to prevent the unit operation Fault due to water shortage of
the system. It is recommended that the outlet pressure of the automatic water supply valve shall be set 0.3 bar
higher than the system static pressure, but the set value shall be lower than the water replenishing pressure
(the pressure of the water replenishing source), otherwise the normal water replenishment cannot be
conducted. In order to ensure normal water replenishment, the automatic water make-up valve is usually
installed at the water return end of the system (water inlet of the water pump). Please make sure the glycol
concentration will not be diluted, when its water system is conducting water replenishing.
A heat-insulating water tank with certain volume shall be installed in water system to prevent the unit from
frequent startup.
The pipe must have independent supporting, and it cannot be supported on the unit.
All water pipes in the system shall be protected with thermal insulation, except for the exhaust valves and
drain outlets so as to facilitate maintenance.
If the refrigerating medium is water, when the ambient temperature is low and if the unit will not be used for a
long period of time, please drain the water inside the unit. If it is only the short shut-down, the water may not
be drained. However, do not cut off unit’s power. If the water pump is not connected to unit’s main board,
please ensure the operation of the water pump. The fan coil in the water system must be installed with
three-way valve, in order to ensure that the water system can circulate smoothly after the anti-freezing water
pump is opened in winter.
If the unit has multiple modules, for the total water inlet and outlet pipe of the water system, each of them
must be provided with a position which is used for installing the temperature sensor, so as to install the water
inlet & outlet temperature sensor of the system. If the auxiliary electrical heating is required to be installed for
Cooke Industries - Phone: +64 9 579 2185 Email: [email protected] Web: www.cookeindustries.co.nz