Viessmann Vitotronic SPS Service Instructions Manual page 49

Overview of fault messages
TID Pp. No. Fault message
71 "High press. (transmitter)"
72 "Sensor fault T ECO C1 or
C2"
73 "Sensor fault T ECO C1 or
C2 outlet"
74 "Sensor fault P ECO C1 or
C2"
75 "No operation due to appl.
limits"
76 "Pause due to appl. limits
V300AS"
77 "Excess temp. in heat
pump casing"
78 "EEV press. diff. too high"
82 "Sensor fault T ECO C1 or
C2"
(cont.)
Effect
All compressors are switched
off.
Economiser switches off but
heat pump continues to run.
Economiser switches off but
heat pump continues to run.
Economiser switches off but
heat pump continues to run.
Heat pump stops.
Heat pump stops.
Heat pump stops.
Heat pump stops.
Economiser switches off but
heat pump continues to run.
Troubleshooting
Cause
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
■
Economiser temperature sen-
sor or connecting lead faulty
Economiser outlet tempera-
ture sensor or connecting lead
faulty
Economiser pressure sensor
or connecting lead faulty
"Application limit" event
counter has reached the coun-
ter set value.
Heat pump runs for a consid-
erable time outside the appli-
cation limit.
Check the temperatures on
the primary and secondary
side.
"Stop due to hot gas" event
counter has reached the coun-
ter set value.
Secondary temperature at out-
let has risen too rapidly.
Check the temperatures on
the secondary side.
Temperature in the heat pump
casing has reached the alarm
set value.
Risk of malfunction of elec-
tronic components
Heat insulation on lines or
■
heat exchanger faulty or fall-
en off
Primary or secondary tem-
■
peratures too high
Expansion valve is no longer
working properly due to high
pressure differential.
Superheating temperature at
expansion valve EEV too high.
Heat pump runs at or beyond
the application limit.
Economiser temperature sen-
sor or connecting lead faulty
49