
EWWD440~850AAYNNO**
Packaged water-cooled water chillers
4PW25558-1B
Installation and operation manual
35
Safety devices for individual compressor errors
For resetting methods in case of abnormal stops. See
O
PERATING
RANGE
Operating limit
When you operate the unit, use it within the operating range below:
■
Standard model
Water flow rate
Use the unit within the following range.
Further, water flow rate is set as a value with the purpose of
protecting the unit on condition that water quality of the unit meets
the standard.
For maintaining the unit performance, use the unit near the rated
water flow rate.
Rate of water quantity can be confirmed with manufacturer’s label.
Table 5: Usable water quantity range
6. Differential pressure error
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Low condenser water temperature
• High unit water temperature
• Temperature of chilled water and
that of condenser water
overturned considerably
Differential pressure required for
lubrication of compressor cannot be
secured
(Not immediately after starting)
7. Main power lost error (When support by separate installation of starter was
done)
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Power failure
• Voltage drop
Loss of power of starter
8. Pump interlock error
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Inadequate pump circuit
• Inadequate interlock circuit
Pump interlock contact does not
return within 180 seconds after the
unit accepts operation command
9. Suction pressure sensor error
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Disorder of sensor alone
• Inadequate insertion of PLC
connection connector
Disconnection or short circuit of
suction pressure sensor
10. Discharge pressure sensor error
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Disorder of sensor alone
• Inadequate insertion of PLC
connection connector
Disconnection or short circuit of
suction pressure sensor
11. Discharge temperature sensor error
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Disorder of sensor alone
• Inadequate insertion of PLC
connection connector
Disconnection or short circuit of
discharge temperature sensor
(Attached to the top of condenser)
12. Chilled water outlet temperature sensor error
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Disorder of sensor alone
• Inadequate insertion of PLC
connection connector
Disconnection or short circuit of
chilled water outlet temperature
sensor
1. Discharge gas 1 or 2 high temperature error
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Refrigerant gas leakage
• Low load continuous operation
outside recommended operation
range
• Clogging of strainer in refrigerant
system
Discharge gas temperature exceeds
set point
2. Potentiometer 1 or 2 full shut error
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Disorder of capacity control
sensor alone
• Inadequate insertion of PLC
connection connector
• Malfunction of motor for capacity
control
Capacity control opening has not
returned to 0% when compressor
starts
3. Motor 1 or 2 overload
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Voltage that falls outside of service
standard was applied
• Big voltage imbalance between
phases
• Power open-phase
• Frequent ON-OFF by shortening
ON-OFF limiting timer intentionally
• Disorder of magnetic switch alone
• Refrigerant gas leakage
• Some valve of the unit closed
• Power phase-reversal
Either one of following 4 points
occurred
• Motor overload
• Power open-phase
• High motor coil temperature
• Power phase-reversal
4. Potentiometer 1 or 2 sensor error
(1)
(1) In the device name, "1" represents left side compressor viewed from the front of
switch box and "2" represents right side compressor.
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Disorder of sensor alone
• Inadequate insertion of PLC
connection connector
Disconnection or short circuit of
capacity control opening sensor
5. No. 1 or 2 discharge temperature sensor error
P
OSSIBILE
CAUSES
D
ETAILS
OF
ACTIVATION
• Disorder of sensor alone
• Inadequate insertion of PLC
connection connector
Disconnection or short circuit of
discharge temperature sensor
(Attached to discharge pipe)
WARNING
Request your dealer to execute necessary repairs.
Imperfection in repair may result in electric shock or fire.
Inspection or repair in case of abnormalities may be
dangerous.
Operation range during continuous stable operation
Usable range during pull-down operation
NOTE
Make sure that the unit operates within the
operating range 1 hour after operation start.
Model
Chiller water (l/min)
Cooling water (l/min)
EWWD440
710-1990
710-1960
EWWD600
930-2720
1030-3020
EWWD850
1270-3020
1420-4150
25
5
4
16
10
15
20
25
30
35
40
45
50
Cooling w
ater outlet
temper
ature °C
Chilled water outlet temperature °C