Daikin EWAT_B User Manual

Operating Manual
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EWAT_B
Local HMI
Network
Auto
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5.5.4 CxOff CondPressHigh – High Condensing Pressure alarm
This alarm is generated in case the Condensing saturated temperature rise above the Maximum condensing saturated
temperature and the control is not able to compensate to this condition.
In case of water cooled chillers operating at high condenser water temperature, if the Condensing saturated temperature
exceeds the Maximum condenser saturated temperature, the circuit is only switched off without any notification on the
screen as this condition is considered acceptable in this range of operation.
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.
String in the alarm list:
CxOff CondPressHigh
String in the alarm log:
 CxOff CondPressHigh
String in the alarm snapshot
CxOff CondPressHigh
One or more condenser fans do not
operate properly (A/C units).
Check if fans protections have been
activated.
Check that the fans can turn freely.
Check that there is not any obstacle to the
free ejection of the air blown.
Condenser pump may not be operating
correctly (W/C units)
Check if the pump can run and give the
required water flow.
Dirty or partially blocked condenser coil
(A/C units).
Remove any obstacle;
Clean the condenser coil using soft brush
and blower.
Dirty condenser heat exchanger (W/C
units)
Clean the condenser heat exchanger.
Inlet air temperature of the condenser is
too high (A/C units).
The air temperature measured at the inlet
of the condenser may not exceed the limit
indicated in the operational range (working
envelope) of the chiller.
Check the location where the unit is
installed and check that there are no any
short circuit of the hot-air blown from the
fans of the same unit, or even from fans of
next chillers (Check IOM for proper
installation).
Entering water temperature at condenser
is too high (W/C units).
Check the cooling tower operation and
settings.
Check the three way valve operation and
settings.
One or more condenser
fan turning in wrong
direction (A/C units).
Check for correct phases sequence (L1,
L2, L3) in the electrical connection of the
fans.
Excessive charge of
refrigerant into the unit.
Check liquid sub-cooling and suction
super-heat to control indirectly the correct
charge of refrigerant.
If necessary recover all the refrigerant to
weight the entire charge and to control if
the value is in line with kg indication on unit
label.
Condensing pressure transducer could not
operate properly.
Check for proper operation of the high
pressure sensor.
Wrong unit configuration (W/C units).
Check that the unit has been configured for
high condenser temperature applications.
Reset
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5.5.5 CxOff EvapPressLow - Low Pressure alarm
This alarm is generated in case the evaporating pressure drops below the Low Pressure Unload and the control is not able
to compensate to this condition.
Symptom
Cause
Solution
Circuit status is Off.
The compressor does not load anymore or
even unload, circuit is stopped
immediately.
Bell icon is moving on controller’s display.
String in the alarm list:
CxOff EvapPressLow
String in the alarm log:
 CxOff EvapPressLow
String in the alarm snapshot
Transitory condition like a fan staging (A/C
units).
Wait until the condition is recovered by
EXV control
Refrigerant charge is low.
Check sight glass on liquid line to see if
there is flash gas.
Measure sub-cooling to see if the charge is
correct.
Protection limit not set to fit customer
application.
Check the evaporator approach and the
corresponding water temperature to
evaluate the low pressure hold limit.
High Evaporator Approach.
Clean the evaporator

Daikin EWAT_B Specifications

General

Brand	Daikin
Model	EWAT_B
Category	Chiller
Language	English