Fault Messages On The Display - Viessmann VITODENS 100-W Installation And Service Instructions Manual

Troubleshooting
Function sequence and possible faults
Yes
Burner in opera-
tion

Fault messages on the display

Displayed System characteris-
fault code tics
30 Burner blocked
38 Burner blocked
51 No DHW heating
52 Burner blocked
59 No DHW heating
5A Burner blocked
36
No
Stops below the set
boiler water tem-
perature and re-
starts immediately
2
Cause
Short circuit, boiler
water temperature
sensor
Lead break, boiler
water temperature
sensor
Short circuit, outlet
temperature sen-
sor
Short circuit, flow
sensor
Lead break, outlet
temperature sen-
sor
Lead break, flow
sensor
(cont.)
Faults are indicated by a flashing fault
code with fault symbol "U" on the dis-
play.
For fault code explanations see the fol-
lowing table.
Measures
Check the boiler water
temperature sensor (see
page 41).
Check the boiler water
temperature sensor (see
page 41).
Check the sensor (see
page 43).
Check connections and
lead; replace sensor if re-
quired.
Check the sensor (see
page 43).
Check connections and
lead; replace sensor if re-
quired.
Check the flue sys-
tem for tightness
(flue gas recircula-
tion); check the
gas flow pressure