Viessmann Vitotronic SPS Service Instructions Manual page 47

Overview of fault messages
TID Pp. No. Fault message
29 51 "Sensor outside measuring
range"
30 G "Sensor outside measuring
range"
31 H "Sensor outside measuring
range"
32 I "Sensor outside measuring
range"
33 J "Sensor outside measuring
range"
34 K "Sensor outside measuring
range"
35 "High pressure control
compressor 1"
36 "High pressure control
compressor 2"
37 "High pressure control
compressor 3"
41 "High press. (transmitter)"
42 20 "Alarm from booster heat-
er"
46 "Low press. (transmitter)"
47 "Low pressure control"
(cont.)
Effect
Heating water buffer cylinder
is no longer charged
The heat pump is switched
off
Compressor 1 is switched off
Compressor 2 is switched off
Compressor 3 is switched off
All compressors are switched
off
Compressor 1 is switched off. Safety high pressure switch
Compressor 2 is switched off.
Compressor 3 is switched off.
All compressors are switched
off.
Enabling of the external heat
generator is switched off.
All compressors are switched
off
All compressors are switched
off
Troubleshooting
Cause
Upper temperature sensor in
heating water buffer cylinder
or connecting lead faulty
Low pressure sensor or con-
necting lead faulty
Oil pressure sensor on com-
pressor 1 or connecting lead
faulty
Oil pressure sensor on com-
pressor 2 or connecting lead
faulty
Oil pressure sensor on com-
pressor 3 or connecting lead
faulty
High pressure sensor or con-
necting lead faulty
has responded (pressure too
high)
For causes, see TID 41
A mechanical reset is required
according to the model of
safety high pressure switch.
Pressure on the high pressure
side has risen above the maxi-
mum permissible level. Heat
can no longer be dissipated.
Circulation pump faulty or
■
flow rate too low
Heat exchanger/condenser
■
contaminated
Air in the system
■
Slider or valve closed
■
See display and operating in-
structions for the external heat
generator
Pressure on the low pressure
side has fallen below the mini-
mum permissible level.
No pressure could be built up.
Circulation pump faulty or
■
flow rate too low
No circulation through evap-
■
orator
Expansion valve faulty
■
Too little refrigerant in refrig-
■
erant circuit
The low pressure sensor in
the heat pump has responded
(pressure too low).
For causes, see TID 46.
47