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Start-up and Operation
Starting procedures
• Switch the water chiller power on, press MODE button on the control panel to choose refrigerating
or heating, and then press ON/OFF button to start the water chiller operation.
• Keep the water chiller operating for more than 30MIN, and when system operation is stable, check
the following items to ensure the normal operation of the water chiller:
1.Check whether the water flow and pressure of the water chiller are stable in a normal range.
2.Test high and low pressure of the water chiller. During normal operation, low pressure shall be
85-145psig (0.586-1.0MPa), while high pressure shall be 2.290-500psig (2.0-3.45MPa).
3.Check current of compressor.
4.Check power supply.
5.Check whether there is water in the sight glass of liquid line.
6.Test system superheat degree. Under ARI circumstances (inlet water temperature at , outlet
water temperature at and ambient temperature at ), normal system superheat degree of each
circuit is 5. In case superheat degree of any circuit measured is beyond this range, superheat
setting of expansion valve shall be appropriately regulated. In such case, the new setting shall be
stabilized in 15-30min.
7.Under ARI circumstances, the normal system supercooling degree of each circuit is 5. In case
supercooling degree of any circuit measured is beyond this range, necessary regulation shall be
carried out following the check of supercooling. In the case of normal superheat but abnormal
supercooling, please contact professional maintenance personnel.
8.In the case of inadequate cooling agent exhibited through running pressure, sight glass,
superheat degree and supercooling degree, leak points shall be identified, and gaseous cooling
agent shall be charged to the circuit. During the water chiller operation, cooling agent is filled
from low pressure line till normal working pressure becomes available. Low running pressure
gives an indication of low supercooling degree, meaning inadequate cooling agent.
9.In case working pressure reveals excessive cooling agent, cooling agent shall be reclaimed from
liquid line little by little (so as to reduce loss of refrigerant oil as far as possible).
• Ensure that all temperature sensors are correctly located with their capillary tubes firmly fixed so
as to prevent vibration and abrasion.
• Check the water chiller, and clear away wastes, tools and parts. Secure all sheet metal parts of the
housing, including control panel and compressor access panel, and restore all screws.
Cautions:
CAUTION
• In winter, close water supply valve of all evaporators, open drain valve and the vent valve in
the pipeline of the water chiller so as to discharge water from the evaporator, and mount a
drain plug. Regarding to ultra-thin top cooling fans, completely release water in the pipeline
by a drain valve, and then open the bottom drain valve to remove all residual water in the
evaporator. In case water in the cold water pipe cannot be completely discharged, proper
antifreezing solution can be injected so as to prevent freezing of residual water that may lead
to damage of the water chiller.
