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Operation Manual
D
–EOMWC00A07-16_02EN
10.4.5
Evaporator Water Freeze Protect
This alarm is generated to indicate that the water temperature (entering or leaving) has dropped below a safety limit.
Control tries to protect the heat exchanger starting the pump and letting the water circulate.
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:
UnitOffCondWaterTmpLo
String in the alarm log:
UnitOffCondWaterTmpLo
String in the alarm snapshot
UnitOffCondWaterTmpLo
Water flow too low.
Increase the water
flow.
Inlet temperature to the evaporator is
too low.
Increase the inlet water temperature.
Flow switch is not working or no water
flow.
Check the flow switch and the water
pump.
Refrigerant temperature become too
low (< -0.6°C).
Check the water flow and filter. No
good heat exchange condition into
the evaporator.
Sensors readings (entering or leaving)
are not properly calibrated.
Check the water temperatures with a
proper instrument and adjust the
offsets.
Wrong freeze limit setpoint.
The freeze limit has not been
changed as a function of glycol
percentage.
Reset
Notes
Local HMI
Network
Auto
It’s required to check if the condenser
has any damage due to this alarm.
10.4.6
Evaporator Water Temperatures Inverted
This alarm is generated any time the entering water temperature is lower than the leaving by 1°C and at least one
compressor is running since 90 seconds.
Symptom
Cause
Solution
Unit status is Off.
All circuits are stopped with a normal
shutdown procedure.
Bell icon is moving on controller’s
display. String in the alarm list:
UnitOffEvpWTempInvrtd String in
the alarm log:
UnitOffEvpWTempInvrtd
String in the alarm snapshot
UnitOffEvpWTempInvrtd
Entering and leaving water
temperature sensors are inverted.
Check cabling of the sensors on the
unit controller.
Check offset of the two sensors with
the water pump running.
Entering and leaving water pipes are
reversed.
Check if the water flows in counter
flow respect to refrigerant.
Water pump operate reverse.
Check if the water flows in counter
flow respect to refrigerant.
Reset
Notes
Local HMI
Network
Auto
