EWAP110~340MBYNN
Packaged air-cooled water chillers
4PW22677-1
Operation manual
16
Symptom 4: The circuit does not start up
Symptom 5: One of the following safety devices is activated
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
Symptom 6: Unit stops soon after operation
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
One of the following safety devices is
activated:
• Compressor thermal protector (Q*M)
• Overcurrent relay (K*S)
• Discharge thermal protector (S*T)
• Low pressure
• High pressure switch (S*PH)
• Reverse phase protector (R*P)
• Freeze-up
Check on the controller and refer to
Symptom 5: One of the following
safety devices is activated
The anti-recycling timer is still active.
The circuit can only start up after
approximately 10 minutes.
The guard timer is still active.
The circuit can only start up after
approximately 1 minute.
The circuit is limited to 0%.
Check the enable/disable capacity
limitation remote contact.
Symptom 5.1: Overcurrent relay of compressor
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
Failure of one of the phases.
Check fuses on the supply panel or
measure the supply voltage.
Voltage too low.
Measure the supply voltage.
Overload of motor.
Reset. If the failure persists, call your
local dealer.
RESET
Push the blue button on the over-
current relay inside the switch box
and reset the controller.
Symptom 5.2: Low pressure
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
Waterflow to water heat exchanger
too low.
Increase the waterflow.
Shortage of refrigerant.
Check for leaks and refill refrigerant,
if necessary.
Unit is working out of its operation
range.
Check the operation conditions of
the unit.
Inlet temperature to the water heat
exchanger is too low.
Increase the inlet water temperature.
Dirty evaporator.
Clean the evaporator or call your
local dealer.
Low pressure safety setting too high.
Refer to the installation manual
"Customization in the service menu",
paragraph "Setting of the minimum
outlet water temperature" for correct
values.
Flowswitch is not working or no
waterflow.
Check the flowswitch and the water
pump.
RESET
After pressure rise, this safety resets
automatically, but the controller still
needs to be reset.
Symptom 5.3: High-pressure switch
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
Condenser fan does not operate
properly.
Check that the fans turn freely. Clean
if necessary.
Dirty or partially blocked condenser.
Remove any obstacle and clean
condenser coil using brush and
blower.
Inlet air temperature of the
condenser is too high.
The air temperature measured at the
inlet of the condenser may not
exceed 43°C.
Fan turning in the wrong direction.
Two phases of the power supply to
the fan motor must be inverted (by a
licensed electrician).
RESET
After pressure decrease, push the
button on the high-pressure switch
and reset the controller.
Symptom 5.4: Fan thermal protector is activated
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
Mechanical failure (fan is blocked).
Check that the fan rotates freely.
Air flow in the unit too low or outdoor
temperature too high.
Clean the air heat exchanger
properly.
RESET
After temperature decrease, the
thermal protector is reset
automatically.
If the protector is activated
frequently, replace the motor or call
your local dealer.
Symptom 5.5: Reverse phase protector is activated
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
Two phases of the power supply are
connected in the wrong phase
position.
Invert two phases of the power
supply (by licensed electrician).
One phase is not connected
properly.
Check the connection of all phases.
RESET
After inverting two phases or fixing
the power supply cables properly,
the protector is reset automatically,
but the controller still needs to be
reset.
Symptom 5.6: Discharge thermal protector is activated
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
Unit is working outside the operation
range.
Check the operation condition of the
unit.
RESET
After temperature decrease, the
thermal protector resets
automatically but the controller still
needs to be reset.
Symptom 5.7: Flowswitch is activated
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
No waterflow or too low waterflow.
Check the water pump and the water
circuit for obstructions.
RESET
After finding the cause, the
flowswitch is reset automatically, but
the controller still needs to be reset.
Symptom 5.8: Freeze-up protection is activated
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
Waterflow too low.
Increase the waterflow.
Inlet temperature to the evaporator is
too low.
Increase the inlet water temperature.
Flowswitch is not working or no
waterflow.
Check the flowswitch and the water
pump.
RESET
After temperature increase the
freeze-up is reset automatically, but
the circuit controller needs to be
reset.
Symptom 5.9: Compressor thermal protector is activated
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
Compressor motor coil temperature
too high.
Compressor is not cooled sufficiently
by the refrigerant medium.
RESET
After temperature decrease the
thermal protector is reset
automatically, but the circuit
controller needs to be reset.
If the protector is activated
frequently, call your local dealer.
P
OSSIBLE
CAUSES
C
ORRECTIVE
ACTION
The schedule timer is activated and
is in off mode.
Work according to the settings in the
schedule timer or disable the
schedule timer.
One of the safety devices is
activated.
Check safety devices (refer to
Symptom 5: One of the following
safety devices is activated
).
Voltage is too low.
Test the voltage in the supply panel
and, if necessary, in the electrical
compartment of the unit (voltage
drop due to supply cables is too
high).
