Other Fault Messages - Viessmann PLC VITOCAL 350-HT PRO Operating Instructions For The System User

Overview of fault messages
ID Fault message
17! "EEV requires min. 1 stage
more"
18 "Sensor fault, refrig."
19 "Refrig. leak, alarm"
20 "All soft starters faulty"
21 "Ctrllr IHE"
22 "Pressure switch, primary cir-
cuit"
28 "All high press. switches
trig."
29 "All winding protectors faulty" The system switches off
30 "All oil press. too low"

Other fault messages

Note
You may acknowledge the following fault messages at
any time. These fault messages do not prevent opera-
tion of the heat pump. If a fault remains active or
occurs several times, please contact your heating con-
tractor or Viessmann Service.
ID Fault message
41 "Replace PLC battery"
42 "Sensor fault, outside temp"
43 "Sensor fault, outlet temp,
evaporator"
44 "Sensor fault, inlet temp, con-
denser"
45 "Sensor fault, inlet temp,
evaporator"
46 "Man. switching act."
47 "Sensor fault, hot gas t"
48 "Sens.fault,oil press.1"
(cont.)
Effects
The system switches off
The system switches off
The system switches off
The system switches off
The system switches off
The system switches off
The system switches off
The system switches off
Effects
The specified set values may be
lost if there is a power failure
The outside temperature cannot
be measured
The outlet temperature of the
evaporator cannot be measured
The inlet temperature of the
condenser cannot be measured
The inlet temperature of the
evaporator cannot be measured
Manual switching does not ena-
ble the system to operate opti-
mally
The hot gas temperature can no
longer be measured
Compressor 1 remains shut
down for as long as the fault is
current
Possible cause
The electronic expansion valve requires
one more compressor in order to operate
optimally
Refrigerant sensor is faulty
The refrigerant sensor has measured an
excessively high concentration of refrig-
erant in the air
All soft starters have a fault status
Overall superheating has not been
reached or hot gas too warm
The pressure in the primary circuit is too
low
All safety high pressure switches have a
fault status.
Note
To reset the safety high pressure
switches, see the heat pump installation
and service instructions.
All winding protectors have a fault status
All oil pressure differentials are too low
Possible cause
The SPS (PLC) battery is almost
or completely drained and must
be replaced
Outside temperature sensor faul-
ty
Faulty temperature sensor at
evaporator outlet
Faulty temperature sensor at
condenser inlet
Faulty temperature sensor at
evaporator inlet
Manual switching in the program
or in the visualisation
Hot gas temperature sensor faul-
ty
The oil pressure sensor of com-
pressor 1 is faulty
Appendix
31