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Installation and operation manual
32
EWWD440~850AAYNNO**
Packaged water-cooled water chillers
4PW25558-1B
Daily inspection
For continuing normal operation of the unit, perform inspections listed
below periodically and keep record of the inspections.
Following criteria indicate the value within normal operating range of
this unit. It does not necessarily mean that the unit is operating
abnormally in case that measured values deviate from the reference
values.
Disposal requirements
Dismantling of the unit, treatment of the refrigerant, oil and any other
parts, must be done in accordance with the relevant local and
national regulations.
C
AUTIONS
WHEN
STOPPING
FOR
A
LONG
TIME
■
Turn OFF the power
■
Drain off
After drain off, in addition to the cleaning of the unit for
preventing corrosion, dry the unit sufficiently or fill it with clean
water (antifreeze in cold climates or areas where outside
temperature reaches 0°C or less at night).
In case you use antifreeze, select antifreeze that does not have
deleterious effect on steel, copper and neoprene rubber.
■
Restart of operation after a long-term stop
Prior to restart of operation after a long-term stop, check
following items:
1. Measure the insulation resistance of the circuit (Use a 500 V DC
insulation-resistance tester).
Make sure that the insulation resistance of the power circuit
is 10 M
Ω
or more and 3 M
Ω
or more for the control circuit.
2. Electrify the unit at least 6 hours before operation.
In addition, prior to full-scale operation, perform an inching of the
compressors. (See
"First operation (Very important)" on
When the ambient temperature is low and preliminary
electrification time to the unit is short, abnormal sound may
occur at first time start of the compressors.
If abnormal sound lasts for 5 seconds or more after starting of
compressors, or the sound does not disappear at starting, stop
operation of the unit and consult your dealer.
Inspection timing
Inspection item
Inspection method
Criteria
Inspection results
Daily inspection
Discharge pressure
Check with pressure gauge
0.7-1.3 MPa
MPa
Suction pressure
Standard model 0.22-0.35 MPa
Power supply voltage
Check with voltmeter
Rated voltage (Stated in
manufacturer’s label)±10%
V
Chilled water outlet temperature
Check with thermometer
5-10°C
°C
Condenser water inlet temperature
25-40°C
Vibration and operating sound
Auscultation/ palpation
There will be no abnormal sound or
vibration
Refrigerant level
Check evaporator level gauge
Liquid level will be visible
No. 1 compressor oil level
Check with oil level gauge
Oil level will be visible
No. 2 compressor oil level
Daily inspection through
touch panel indication
Motor 1 current
—
A
Motor 2 current
Discharge pressure
0.7-1.3 MPa
MPa
Suction pressure
Standard model 0.22-0.35 MPa
load 1
—
%
load 2
Chilled water inlet temperature
°C
Chilled water outlet temperature
5-10°C
Condenser water inlet temperature
25-45°C
Condenser water outlet temperature
30-50°C
Discharge temperature
40-90°C
Discharge overheat temperature
8-30°C
Discharge gas temperature 1
40-90°C
Discharge gas temperature 2
Operating time 1
—
Hr
Operating time 2
Number of ON-OFFs 1
Times
Number of ON-OFFs 2
CAUTION
When you stop the unit for a long time, do not
leave it with water piping filled with water
Fill the water piping with antifreeze or drain off.
Leaving the water piping filled with water may lead to
water leakage or damage of heat exchanger tubes.