Maintenance
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Part 6: Maintenance
6.1. Unit’s operation process
Check whether the external packing of the unit is in good condition
Check whether the attached accessories and the files are complete
Carefully read this IOM
Hoisting and unpacking
The unit shall be installed in specified position
Install the main machine (including the stop valve, filter, water pressure meter, water flow switch, expansion tank
and temperature gauge etc.)
Connect the power line, communication line, total waterway system’s water flow switch, module’s water flow
switch, system’s outflow water/backwater temperature sensor, etc., which are required to be connected.
Clean the water pipeline through bypassing inlet and outlet pipes of main unit conduit (close the water inlet and
outlet stop valve);
Drain the air from the water system and fill it with water;
Pre-check before operation for the following items:
A. Power voltage
B. Power supply connection, especially check the section of power supply wire, and fastening of ground connection
and connection terminal;
C. Water pipes must be kept clean and protected from any pollutant or impurity. At last, rinse the water pipe three
times (with the unit bypassed) to guarantee all impurities and oxides in the circulation system have been removed.
D. Confirm that the water source is connected correctly;
E. Check if the water circulation system works effectively, if the water system is filled with water, and make sure
there are no leakage or bubble problems.
When there is no problem with the above contents, power up the unit, complete the initialization and parameter
setting of the controller, and let the oil heating band of the compressor be heated for at least 12 hours
If it is the module machine, set one unit as the main machine (1# module), and connect system’s inlet and outlet
water temperature sensor, water flow switch and external interlock to this machine; If the main machine (1#
module) is replaced, you must reset another one.
Operate the unit according to the “Description of operation” in Chapter 4 and Chapter 5 of this manual; Check the
following items after the unit’s operation is stable in the first time:
A. Inlet and outlet water temperature of the heat exchanger
B. Water flow at the outlet of the heat exchanger
C. Compressor’s operating current when the unit is in operation
D. Please use the needle valve installed inside the machine to check the operating temperature of system’s
refrigerant (related to the pressure)
Please refer to the following requirements when conducting inspection:
----High-pressure side: the saturation condensing temperature should be about 3-8 degrees higher than the air
conditioner’s cooling inlet and outlet water temperature;
----Low-pressure side: The saturation evaporation temperature should be about 3-8 degrees lower than the air
conditioner’s freezing inlet and outlet water temperature.
6.2. Periodic Care and Maintenance
Prior to shipment, all machines have been strictly tested and inspected to ensure that all products are in good
performance and remain in perfect working condition when leaving the factory. However, in order to ensure that the
machine can be operated well for a long time, it is necessary to strictly implement the following periodic maintenance
items:
The following instructions are for users only. All items shall be strictly implemented on a regular basis to avoid
paying expensive maintenance costs.
Regular maintenance does not require special training.
Inspection and cleaning of water-side heat exchanger
If you want to determine whether the water-side heat exchanger is clean or not, please check the water temperature
at heat exchanger’s water inlet and outlet and compare them with the saturation temperature. For the heat exchanger of
the efficient operation, after the mean value of the water temperature at the water inlet and outlet of the heat exchanger
is subtracted by the saturation evaporation temperature of the refrigerant on the evaporation side or the saturation
Cooke Industries - Phone: +64 9 579 2185 Email: [email protected] Web: www.cookeindustries.co.nz