
90
Fault code dis-
played
System characteristics
Cause
Measures
0F
Control mode
Maintenance
"0F" is only displayed in
the fault history
Service required
Note
After servicing, set code "24:0".
20
Regulates without flow tem-
perature sensor (low loss
header)
Short circuit, system flow
temperature sensor
Check low loss header sensor (see
page 104)
21
Control mode
Display fault in energy cock-
pit
Sensor outside tolerance
range
Check sensor on DHW cylinder
and collectors
22
Control mode
Display fault in energy cock-
pit
Sensor outside tolerance
range
Check sensor on DHW cylinder
and collectors
23
Control mode
Display fault in energy cock-
pit
Incorrect commissioning
Determine solar circuit flow rate (if
installed) and enter value estab-
lished
24
Control mode
Display fault in energy cock-
pit
DHW circulation pump not
working
Check setting of parameter 39
("
General"
group). If required, car-
ry out an actuator test.
25
Control mode
Display fault in energy cock-
pit
Transfer pump not work-
ing
Check setting of parameter 20
("
Solar
" group). If required, carry
out an actuator test.
26
Control mode
Display fault in energy cock-
pit
DHW circulation pump
and transfer pump not
working
Check settings of parameter 20
("
Solar
" group) and parameter 39
("
General
" group). If required, car-
ry out an actuator test.
27
Control mode
Display fault in energy cock-
pit
Incorrect commissioning
Determine solar circuit flow rate (if
installed) and enter value estab-
lished
28
Regulates without flow tem-
perature sensor (low loss
header)
Lead break, system flow
temperature sensor
Check low loss header sensor (see
page 104)
If no low loss header sensor is
connected, set parameter 52:0.
30
Burner blocked
Short circuit, boiler water
temperature sensor
Check boiler water temperature
sensor (see page 104)
38
Burner blocked
Lead break, boiler water
temperature sensor
Check boiler water temperature
sensor (see page 104)
40
Mixer being closed
Short circuit, flow temper-
ature sensor, heating cir-
cuit 2 (with mixer)
Check flow temperature sensor
(see page 109)
44
Mixer being closed
Short circuit, flow temper-
ature sensor, heating cir-
cuit 3 (with mixer)
Check flow temperature sensor
(see page 109)
48
Mixer being closed
Lead break, flow tempera-
ture sensor, heating circuit
2 (with mixer)
Check flow temperature sensor
(see page 109)
49
Mixer being closed
Incorrect assignment of
extension for mixer, heat-
ing circuit 2
Check and adjust rotary selector
S1 (see page 109)
4C
Mixer being closed
Lead break, flow tempera-
ture sensor, heating circuit
3 (with mixer)
Check flow temperature sensor
(see page 109)
Troubleshooting
Fault codes
(cont.)
5789 302 GB
Diagnosis
Summary of Contents for B2TB
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Page 117: ...117 Parts lists Hydraulics 5789 302 GB Components ...
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