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Air and Water cooled inverter chillers and heat pump
EWAD TZ - EWAD TZ B - EWWD VZ
Air and Water cooled inverter chillers
and heat pump
D-EOMZC00105-17EN
Operation Manual
65/84
Symptom
Cause
Solution
Unit status is Off.
All circuits are stopped immediately. Bell
icon is moving on controller’s display.
String in the alarm list:
UnitOffPhaveVoltage
String in the alarm log:
UnitOffPhaveVoltage
String in the alarm snapshot
UnitOffPhaveVoltage
Loss of one phase.
Check voltage level on each of the phases.
Not correct sequence connection of
L1,L2,L3.
Check sequence of L1, L2, L3 connections
according indication on chiller’s electrical
scheme.
Voltage level on the unit’s panel is not in
the allowed range (±10%).
Check that voltage level on each phases is
into the allowed range that is indicated on
the chiller label.
Is important to check the voltage level on
each phases not only with chiller not
running, but mainly with chiller running
from minimum capacity up to full load
capacity. That's because voltage drop can
occur from a certain unit cooling capacity
level, or because of certain working
condition (i.e. high values of OAT);
In these cases the issue can be related
with the sizing of power cables.
There is a short-circuit on the unit.
Check for correct electrical isolation
condition of each unit’s circuit with a
Megger tester.
Reset
Notes
Local HMI
Network
Auto
6.4 Circuit Alerts
6.4.1
Economizer Pressure Sensor fault (A/C units only)
This alarm is generated to indicate that the sensor is not reading properly.
Symptom
Cause
Solution
Circuit status is On.
Economizer is Off.
Bell icon is moving on controller’s display.
String in the alarm list:
Cx EcoPressSen
String in the alarm log:
Cx EcoPressSen
String in the alarm snapshot
Cx EcoPressSen
Sensor is broken.
Check
for
sensor
integrity.
Check correct sensors operation according
information about mVolt (mV) range related
to pressure values in kPa.
Sensor is shorted.
Check if sensor is shorted with a resistance
measurement.
Sensor is not properly connected (open).
Check for correct installation of the sensor
on refrigerant circuit pipe. The transducer
must be able to sense the pressure through
the valve’s needle.
Check for absence of water or humidity on
sensor electrical contacts.
Check for correct plug-in of the electrical
connectors.
Check for correct sensors wiring also
according electrical scheme.
Reset
Notes
Local HMI
Network
Auto
6.4.2
Economizer Temperature Sensor fault (A/C units only)
This alarm is generated to indicate that the sensor is not reading properly.
Symptom
Cause
Solution
Circuit status is On.
Economizer is Off.
Bell icon is
moving on controller’s display.
String in the alarm list:
Cx EcoTempSen
String in the alarm log:
Cx EcoTempSen
Sensor is shorted.
Check for sensor integrity.
Check
correct
sensors
operation
according information about kOhm (k
)
range related to temperature values.
Sensor is broken.
Check if sensor is shorted with a
resistance measurement.