Viessmann PLC VITOCAL 350-HT PRO Service Instructions For Contractors page 33

Overview of fault messages
ID Fault message
49 "Sensor fault,oil press.2"
50 "Sensor fault,oil press.3"
51 "Sensor fault, room temp"
52 "Soft starter 1 faulty"
53 "Soft starter 2 faulty"
54 "Soft starter 3 faulty"
55 "Oil press. diff. 1 too low"
56 "Oil press. diff. 2 too low"
57 "Oil press. diff. 3 too low"
58 "Winding protectn 1 trig."
59 "Winding protectn 2 trig."
60 "Winding protectn 3 trig."
61 "High press. switch 1 trig."
62 "High press. switch 2 trig."
63 "High press. switch 3 trig."
64 "Refrig. leak, pre-alarm"
65 "Suct. switching act."
66 "Fault, oil sump heater 1"
(cont.)
Effects
Compressor 2 remains shut
down for as long as the fault is
current
Compressor 3 remains shut
down for as long as the fault is
current
The room temperature cannot
be measured
Compressor 1 switches off and
attempts to start up again after
the restart block
Compressor 2 switches off and
attempts to start up again after
the restart block
Compressor 3 switches off and
attempts to start up again after
the restart block
Compressor 1 remains shut
down until the fault is acknowl-
edged
Compressor 2 remains shut
down until the fault is acknowl-
edged
Compressor 3 remains shut
down until the fault is acknowl-
edged
Compressor 1 remains shut
down until the fault is acknowl-
edged
Compressor 2 remains shut
down until the fault is acknowl-
edged
Compressor 3 remains shut
down until the fault is acknowl-
edged
Compressor 1 remains shut
down until the fault is acknowl-
edged
Compressor 2 remains shut
down until the fault is acknowl-
edged
Compressor 3 remains shut
down until the fault is acknowl-
edged
Room ventilation is switched on
The application limits are not be-
ing observed
Compressor 1 switches on auto-
matically as soon as the fault is
no longer current
Troubleshooting
Possible cause
The oil pressure sensor of com-
pressor 2 is faulty
The oil pressure sensor of com-
pressor 3 is faulty
Room temperature sensor faulty
Soft starter of compressor 1 is
faulty
Soft starter of compressor 2 is
faulty
Soft starter of compressor 3 is
faulty
Oil pressure differential in com-
pressor 1 is too small
Oil pressure differential in com-
pressor 2 is too small
Oil pressure differential in com-
pressor 3 is too small
Winding protection of compres-
sor 1 is faulty
Winding protection of compres-
sor 2 is faulty
Winding protection of compres-
sor 3 is faulty
High pressure switch of com-
pressor 1 is faulty
High pressure switch of com-
pressor 2 is faulty
High pressure switch of com-
pressor 3 is faulty
The refrigerant sensor has meas-
ured an average concentration of
refrigerant in the air
Suction switching is still active in
the visualisation
The oil sump heater of compres-
sor 1 was switched off for too
long
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