Viessmann Vitopend 100-W - Page 75

75
Displayed
fault code
System character-
istics
Cause Measures
F18 Continuous opera-
tion
Lead break, out-
side temperature
sensor or room
temperature sen-
sor
Check the sensor (see
page 77).
F30 Burner locked out Short circuit, boiler
water temperature
sensor
Check the boiler water
temperature sensor (see
page 80).
F38 Burner locked out Lead break, boiler
water temperature
sensor
Check the boiler water
temperature sensor (see
page 80).
F51 No DHW heating Short circuit, outlet
temperature sen-
sor/cylinder tem-
perature sensor
Check the sensor (see
page 80).
F59 No DHW heating Lead break, outlet
temperature sen-
sor/cylinder tem-
perature sensor
Check the sensor (see
page 80).
F6F WLAN connection in-
terrupted
Communication
between control
unit and WLAN
module interrupted
Check connecting cable
between control unit and
WLAN module.
Check setting of parame-
ter P06 and P07.
F70 Function at the ex-
ternal extension faul-
ty
Short circuit, col-
lector temperature
sensor S1 at the
external extension
Check sensor.
Installation and
service instruc-
tions for external
extension
F78 Function at the ex-
ternal extension faul-
ty
Lead break, col-
lector temperature
sensor S1 at the
external extension
Check sensor.
Installation and
service instruc-
tions for external
extension
Troubleshooting
Fault display
(cont.)
5837146
Service