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Start-up and Operation
Long-term shutdown
• For long-term shutdown, the following procedures shall be carried out before system halt:
1. Check whether cooling agent piping leaks, and if so, be sure to have it repaired.
2.Maintain water pump and air conditioning plant as proposed by manufacturer.
3.Discharge all circulating water from the system, unscrew dewatering outlet in the water
supply and return circuit, dismantle side panel of the water chiller, and unscrew the dewatering
outlet in the bottom of water pump and plate type heat exchanger so as to ensure complete
discharge of circulating water.
4.Turn off power switch of the water chiller and water pump.
Restarting the system after long-term shutdown
1.Open the valve of the water return and supply pipeline, and charge clean water into the cold
water pipeline. Be sure to exhaust at the time of water charge, and close the vent valve when
the system is full of water.
2.Bring connection of flow switch into short circuit so as to measure the water system.
3.Switch on power switch of the water chiller.
4.Press ON/OFF button on the control panel to start the water chiller. When cold water is circulated
in the water system, check whether there is any piping joint leaking.
5.Regulate flow of the cold water pipeline by a balance valve, and check the water pressure of the
water chiller.
6.Regulate the flow switch (arranged in the water discharge pipe of the water chiller), so as to
ensure normal running.
7.Press ON/OFF button on the control panel to stop the water chiller.
8.Restore connection of the flow switch.
In this way, the water chiller can run normally at once.
System protection
Low voltage protection (LP1, LP2)
A low voltage switch is provided to protect the water chiller. When the operation voltage is
below 21±7psig(1.145±0.048MPa), compressor operation is stopped, and when it reaches
36±7psig(0.248±0.048MPa), compressor operation is automatically restored. Two-minute short
circuit is necessary for starting up, in case of unnecessary trip.
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.
CAUTION
• During water pump operation, regulate water flow to half of maximum flow, and disconnect
the contact of the flow switch. Please use ohmmeter to verify if the connection point of the
switch is open or close.
