Checking And Acknowledging Faults - Viessmann VITODENS 300 Service Instructions Manual

Troubleshooting
Calling up current fault codes
Fault display design
A Fault symbol
B Plain text fault display (only for
weather-compensated control
units)
C Fault number
D Fault code
1. Calling up acknowledged fault
messages
Press d for approx. 3 seconds.
The fault will then be displayed.

Checking and acknowledging faults

Weather-compensated control units
76
(cont.)
4. E in the display indicates that the
burner control unit is locked out.
After the fault has been removed,
acknowledge by pressing reset E.
Plain text fault display
&
Burner control unit
&
Outside temperature sensor
&
Flow sensor
&
Boiler sensor
&
Mixed flow sensor
&
DHW cylinder sensor
&
Flue gas sensor
&
DHW outlet sensor
&
Room temperature sensor
&
Collector sensor
&
Solar DHW sensor
&
Remote control
2. Select the acknowledged fault
with a or b.
Red fault indicator U flashes for all
faults.
A fault message code flashes in the
programming unit display when a fault
message is issued.
Any fault codes present may be called
up with a or b.