Viessmann VITODENS 200-W Installation And Service Instructions Manual page 61

Fault codes
(cont.)
Fault code dis- System characteristics
played
20 Regulates without flow tem-
perature sensor (low loss
header).
28 Regulates without flow tem-
perature sensor (low loss
header).
30 Burner blocked
38 Burner blocked
50 Type B2HB only:
No DHW heating by the boil-
er
51 No DHW heating by the boil-
er
58 Type B2HB only:
No DHW heating by the boil-
er
59 No DHW heating by the boil-
er
70 Burner blocked
71 Burner blocked
73 Burner blocked
74 Burner blocked or in a fault
state
75 Burner blocked or in a fault
state
76 Burner blocked or in a fault
state
Cause
Short circuit, flow temper-
ature sensor
Lead break, flow tempera-
ture sensor
Short circuit, boiler water
temperature sensor
Lead break, boiler water
temperature sensor
Short circuit, cylinder tem-
perature sensor or comfort
sensor
Short circuit, outlet tem-
perature sensor
Lead break, cylinder tem-
perature sensor or comfort
sensor
Lead break, outlet temper-
ature sensor
Gas pressure switch pre-
vents burner start.
Mains voltage too low
Feedback input from inter-
nal H1 extension prevents
burner start.
Temperature limiter earth
fault
Internal H1/H2 extension
earth fault
Gas pressure switch earth
fault
Troubleshooting
Measures
Check low loss header sensor (see
page 74)
Check low loss header sensor (see
page 74).
If no low loss header sensor is
connected, set code 52:0.
Check the boiler water temperature
sensor (see page 74).
Check the boiler water temperature
sensor (see page 74).
Check cylinder temperature sensor
(see page 74) or comfort sensor
(see page 75)
Check the sensor (see page 75).
Check cylinder temperature sensor
(see page 74) or comfort sensor
(see page 75).
Check the sensor (see page 75).
Check gas supply (gas pres-
■
sure).
If installed: Check gas pressure
■
switch for correct function.
If necessary, disconnect plug 111
from the control unit and check
whether the burner starts.
Check the power supply.
Check that internal H1 extension
and any devices connected to it
are correctly connected and work-
ing properly (internal: Plug 53/96
power interruption)
Check temperature limiter, con-
necting cables and plug-in connec-
tion for contact to earthed compo-
nents. Remove contact if necessa-
ry.
Press reset button R.
Check internal H1/H2 extension,
connecting cables and plug-in con-
nection for contact to earthed com-
ponents. Remove contact if neces-
sary.
Press reset button R.
Check gas pressure switch, con-
necting cables and plug-in connec-
tion for contact to earthed compo-
nents. Remove contact if necessa-
ry.
Press reset button R.
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