EWWQ090G ÷ EWWQ720L - R410A - Water-cooled scroll chillers
EWLQ090G ÷ EWLQ720L - R410A - Condenser less
EWHQ100G ÷ EWHQ400G - R410A - Heat pump scroll chillers
EWAQ-G 075
- R410A - Air-cooled scroll chillers
EWAQ-
- R410A - Air-cooled scroll chillers
EWYQ-
- R410A - Air-cooled scroll heat pumps
Air and Water cooled scroll chillers & heat pump
Operation
Manual
Operation Manual
78
EWWQ - EWLQ - EWHQ
EWAQ - EWYQ
Air or Water cooled scroll chiller &
heat pump
D-EOMHW00107-15EN
This means that this alarm is generated if at least one of the previous digital contact is open. When
this happens an immediate shutdown of the compressors and all the other actuators in this circuit
is commanded.
Symptom
Cause
Solution
Circuit status is Off.
The compressor does not load
anymore or even unload, circuit is
stopped.
Bell icon is moving on controller’s
display.
Led on the button 2 of External HMI is
blinking
String in the alarm list:
+CxOff CircAlm
String in the alarm log:
CxOff CircAlm
String in the alarm snapshot:
CxOff Circ Alm
Mechanical High Pressure Switch
(MHPS) open
Perform same check of the High
Pressure Alarm 6.1.7.3
MHPS damaged or not calibrated.
Check for correct plug-in of the
electrical connectors.
Check for proper operation of the high
pressure switch.
Compressor 1/2 Thermal Protection
open
Excessive charge of refrigerant.
Check liquid sub-cooling and suction
super-heat to control indirectly the
correct charge of refrigerant
Check the correct operation of the
electronic expansion valve. Blocked
valve can to impede the correct
refrigerant flow.
Compressor 1/2 Soft Starter Failure
Check Alarm code on the Soft Starter
and
refer
to
the
related
documentation to fix the alarm.
Check the size of the Soft Starter
compared
with
the
associated
compressor maximum current.
6.1.7.6 Start Fail Alarm
This alarm can occurs only if the condenser less unit type is configured (see section 0). This alarm
is generated just the UC recognizes a low evaporating pressure and a low saturated condensing
temperature at the starting of the circuit. This alarm is auto-reset just occurs, as the unit tries
automatically to restart the circuit. At the third occurrence of this failure a Restart Fault Alarm is
generated (see alarm 6.1.7.7).
Symptom
Cause
Solution
Circuit status is Off.
The circuit is stopped.
Bell icon is moving on controller’s
display.
Led on the button 2 of External HMI is
blinking
String in the alarm list:
+Cx StartFailAlm
String in the alarm log:
Cx StartFailAlm
String in the alarm snapshot:
Cx StartFail Alm
Low outside ambient temperature
Check the operating condition of the
condenser-less unit
Refrigerant charge low.
Check sight glass on liquid line to see
if there is flash gas.
Measure sub-cooling to see if the
refrigerant charge is correct.
Condensing Setpoint not correct for
the application
Check if necessary to increase the
condensing saturated temperature
setpoint
Dry cooler not correctly installed
Check that the dry cooler is safe from
strong wind
Evaporator or condensing sensor
pressure broken or not correctly
installed
Check the proper operation of the
pressure transducers.
