FRIULAIR PURESTREAM CHILLERS CWE-Q 041, Use And Maintenance Manual

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7425MUM753 Model: CWE-Q - Use and Maintenance Manual Rev. 15
Cause
Alarm signal or
symptom
Solution Execution
6. Fans don't start
Very low outside air temperatures and
consequent intervention of the
condensation control
Fan icon off.
Condensation pressure
normal
The machine is working
anyway
No voltage output from the fan-speed
regulator
Fan icon on and fans
stopped
Check the voltage output from the
regulator and replace, if
necessary
Specialised
personnel
Intervention of the thermal protection
inside the fan OR
magnetothermic protection of the fan
open (QV1-QV2)
AC25
Fans thermal protection
Check that the working conditions
of the machine (outside air
temperature) are compatible with
the operating limits. Wait for the
fan motor to cool.
User
Fan fuse blown.
Fan icon on and fans
stopped
Look for short circuits in the motor
windings of the fans.
Check the fan roller bearings.
Specialised
personnel
Electrical connections of the fans
loose
Fan icon on and fans
stopped
Check and tighten
Specialised
personnel
7. The unit is working without ever stopping
Excessive thermal load.
Reduce the thermal load.
Reduce the temperature of
the incoming water and/or the
flow-capacity of the water by
closing the exit tap of the unit
a little.
User
No refrigerant. See point 8
8. Compressor suction pipe covered with frost
No refrigerant.
High superheating, low
subcooling and high
discharge temperature
of the compressor.
Traces of oil on the
refrigerant circuit.
Check the refrigerant circuit
with a leak detector.
Repair any ruptures and
recharge the circuit.
Specialised
personnel
9. The pump doesn't start
Excessive water flow-capacity.
Magnetothermic protection of the
pump open (QP1-QP2)
AP26, AP27
Pump 1, 2 thermal protection
alarm
Reduce the flow-capacity of the
water by closing the output tap of
the pump a little bit.
Rearm the thermomagnetic
protection of pump QP1.
User
Short circuit or overcurrent.
AP26, AP27
Pump 1, 2 thermal protection
alarm
Look for a short circuit in the
winding of the pump motor.
Check for possible over-
absorption of current due to too
low voltage; check the power
supply voltage.
Specialised
personnel
10. The unit starts and stops alternatively;
The outlet water temperature varies greatly
Low water flow
Verify the water flow.
Open the water shut-off valves of
the plant.
If it is possible, reduce the
pressure drop of the water circuit.
If it is possible, add a pump with
proper available pressure.
Specialised
personnel