Daikin MICROTECH III Operating Manual page 39

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
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
Reset
Local HMI
Network
Auto
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
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
Reset
Local HMI
Network
Auto
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Cause
Water flow too low.
Inlet temperature to the evaporator is
too low.
Flow switch is not working or no water
flow.
Refrigerant temperature become too
low (< -0.6°C).
Sensors readings (entering or leaving)
are not properly calibrated.
Wrong freeze limit setpoint.



Cause
Entering and leaving water
temperature sensors are inverted.
Entering and leaving water pipes are
reversed.
Water pump operate reverse.



Operation Manual
Solution
Increase the water
flow.
Increase the inlet water temperature.
Check the flow switch and the water
pump.
Check the water flow and filter. No
good heat exchange condition into
the evaporator.
Check the water temperatures with a
proper instrument and adjust the
offsets.
The freeze limit has not been
changed as a function of glycol
percentage.
Notes
It's required to check if the condenser
has any damage due to this alarm.
Solution
Check cabling of the sensors on the
unit controller.
Check offset of the two sensors with
the water pump running.
Check if the water flows in counter
flow respect to refrigerant.
Check if the water flows in counter
flow respect to refrigerant.
Notes
D–EOMWC00A07-16_02EN