Pre-Startup Checks; General - Daikin EWWQ380B-SS Installation, Operation And Maintenance Manual

Water-cooled screw chillers
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Pre-startup checks

General

Once the machine has been installed, use the following procedure to check that it has been done correctly:
Switch off the power supply of the machine before performing any checks.
Failure to open the power switches at this stage can result in serious injury to the operator or even death.
Inspect all the electrical connections to the power circuits and to the compressors, including t he contactors, fuse carriers
and electrical terminals and check that they are clean and well secured. Even though these checks are carried out at the
factory on every machine that is shipped, vibrations during transportation may loosen some electrical conn ections.
Check that the electrical terminals of cables are well tightened. A loose cable can overheat and give rise to problems
with the compressors.
Open discharge, liquid, liquid injection and suction (if installed) valves.
Do not start up the compressors if the delivery, liquid, liquid injection or suction valves are closed. Failure to open
these valves can cause serious damage the compressor.
It is absolutely forbidden to close the valves on the delivery and suction piping when the unit is running.
These valves can be closed only when the compressor is off during maintenance of the unit. This operation must be
carried out by qualified technical personnel holding the qualifications requested by local and/or European laws and
with the adoption of the foreseen Personal and Collective Protection Devices.
Check the power supply voltage at the general door-block disconnector switch terminals. The power supply voltage must
be the same as that on the nameplate. Maximum allowed tolerance  10%.
Voltage unbalance between the three phases must not exceed  3%.
The unit comes with a factory-supplied phase monitor that prevents compressors from starting if the phase sequence is
incorrect. Properly connect the electrical terminals to the disconnector switch so as to ensure alarm-free operation. If the
phase monitor triggers an alarm once the machine has been powered, just invert two phases at the general
disconnecting switch supply (unit power supply). Never invert the electrical wiring on the monitor.
Starting up with the wrong sequence of phases irreparably compromises operation of the compressor. Ensure that
phases L1, L2 and L3 correspond in sequence to R, S, and T.
Fill the water circuit and remove air from the system's highest point and open the air valve above the evaporator shell.
Remember to close it again after filling. The design pressure on the water side of the evaporator is 10.0 bar. Never
exceed this pressure at any time during the life of the machine.
Before putting the machine into operation, clean the water circuit. Dirt, scaling, corrosion residue and other foreign
material can accumulate inside the heat exchanger and reduce its heat exchanging capacity. Pressure drops can
increase as well, thus reducing water flow. Proper water treatment therefore reduces the risk of corrosion, erosion,
scaling, etc. The most appropriate water treatment must be determined locally, according to the type of system and
local characteristics of the process water.
The manufacturer is not responsible for damage to or malfunctioning of equipment caused by failure to treat water or
by improperly treated water.
CAUTION
CAUTION
ATTENTION
CAUTION
IMPORTANT
D–EIMWC00508-16EN - 27/48

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