33
ID
Fault message
Effects
Possible cause
67
"Fault, oil sump heater 2"
Compressor 2 switches on auto-
matically as soon as the fault is
no longer current
The oil sump heater of compres-
sor 2 was switched off for too
long
68
"Fault, oil sump heater 3"
Compressor 3 switches on auto-
matically as soon as the fault is
no longer current
The oil sump heater of compres-
sor 3 was switched off for too
long
69
Pre-alarm, evaporation temp
too low
A compressor switches off to al-
low the evaporation temperature
to rise. It switches on again as
soon as the restart block time
has elapsed
At least one compressor has had
to switch off due to the evapora-
tion temperature being too low
70
Pre-alarm, condensatn temp
too high
A compressor switches off to al-
low the condensation tempera-
ture to drop. It switches on again
as soon as the restart block time
has elapsed
At least one compressor has had
to switch off due to the conden-
sation temperature being too
high
71
"Sensor fault, buff. t, HWBC
top"
Cylinder charging of the heating
water buffer cylinder is no longer
activated
Heating water buffer cylinder
temperature sensor, top is faulty
72
"Sens. fault, buff. t, HWBC
bottom"
Cylinder charging of the heating
water buffer cylinder is no longer
activated
Heating water buffer cylinder
temperature sensor, bottom is
faulty
73
"Ext. set value, HW buffer cyl"
Cylinder charging of the heating
water buffer cylinder is no longer
activated
External set value from higher
ranking system is outside the
range
74
"Sensor fault, temp, resid.
heat"
The residual heat function is not
activated
Flow temperature sensor, residu-
al heat is faulty
75
"Sensor fault, coolant temp."
The coolant buffer cylinder is not
being cooled
Coolant flow temperature sensor
is faulty
76
"Sensor fault, buffer t, CBC
top"
The coolant buffer cylinder is not
being cooled
Coolant buffer cylinder tempera-
ture sensor, top is faulty
77
"Sensor fault, buffer t, CBC
bottom"
The coolant buffer cylinder is not
being cooled
Coolant buffer cylinder tempera-
ture sensor, bottom is faulty
78
"Sensor fault, flow temp,
DHW"
The domestic hot water is not
being heated
Flow temperature sensor, DHW
heating is faulty
79
"Sensor fault, cylinder t,
DHW"
The domestic hot water is not
being heated
DHW cylinder temperature sen-
sor is faulty
80
"Modbus RS485"
Communication via ModBus
RS484 may not be possible
Faulty configuration
81
"Modbus IP"
Communication via ModBus IP
may not be possible
Faulty configuration
82
"M2 flash not installed"
It may not be possible to save
the configuration and log data
SD card fault
83
"Modbus server TCP"
Communication via ModBus IP
may not be possible
Faulty configuration
84
"Failed to save conf. and set
values"
Set values cannot be saved
Write access to the SD card de-
nied or not possible
85
"Failed to load conf. and set
values"
Set values cannot be loaded
Read access to the SD card has
not been granted
86
"Risk of frost"
The heat pump output is re-
duced
The evaporation temperature has
undershot the frost protection
value
Appendix
Overview of fault messages
(cont.)
5801 531 GB
