Troubleshooting By Alarm Code - Zanotti Zer0 120 Workshop Manual

5.3 TROUBLESHOOTING BY ALARM CODE

Icon Alarm
PrL
Low-
PMI pressure
PrH
High-
PMS
pressure
Electric
motor
F1t
protection
FtB
(only for
stand- by
mode units)
E01
Probe failure
Description
Following a signal from the low-
pressure switch , the display
shows the led alarm
error code PRl(PrL).
When the correct pressure
value is restored, the unit
restarts automatically.
If there are multiple signals, the
alarm PMI(PMI) is displayed
which stops the unit completely
Following a signal from the
high-pressure switch , the
display shows the led alarm
and error code PRh(Prh).
When the correct pressure
value is restored, the unit
restarts automatically.
If there are multiple signals, the
alarm PMS(PMS), is displayed
which stops the unit
completely.
Following a signal from the
electric motor protection, the
display shows the led alarm
and error code F1t(F1t).
When the correct pressure
value is restored, the unit
restarts automatically
If there are multiple signals, the
alarm ftb(Ftb), is displayed
which stops the unit completely
The display show E01(E01) the
led alarm
Possible causes
- Refrigerant leakage
- Evaporator packaged
and
of ice
- Failure of evaporator
fans
- Outside temperature
very low (<32°F)
- Failure of condenser
fans
- Dirty condenser of
insufficient air flow
- Moisture in the circuit
- Stand-by motor
defective
- Low supply voltage
- Power source too far
from the unit
- CPR valve set
incorrectly
- Temperature probe
defective or not
properly connected
53
Possible remedies
- Perform a manual
defrost and ensure
that the evaporator is
clean and free of ice
- Confirm the correct
operation of the
evaporator fans
- Clean the condenser
- Check the
condenser fan
- Check if there are
no obstacles in front
of the condenser
such as to obstruct
the proper air flow
- Check if the voltage
is correct
- Check if there is a
short circuit in the
stand-by motor
- Check the
parameter setting of
the thermal overload
relay
- Check the probe
connection