Viessmann VITOCAL 300-G Installation And Service Instructions Manual page 133

Messages
(cont.)
Message
System characteristics Cause
54 DHW solar
No heating of the DHW
cylinder/primary store by
the solar thermal system;
solar circuit pump
remains OFF
58 DHW sensor top
DHW heating is blocked
5C DHW solar
No heating of the DHW
cylinder/primary store by
the solar thermal system;
solar circuit pump
remains OFF
60 Buffer cylinder sensor
Buffer cylinder is heated
once every hour. Heating
stops according to set
value of the return tem-
perature sensor
63 Ext. heat source
External heat source is
blocked. Instantaneous
heating water heater (if
installed) is enabled
68 Buffer cylinder sensor
Buffer cylinder is heated
once every hour. Heating
stops according to set
value of the return tem-
perature sensor
Short circuit, Vitosolic
cylinder temperature
sensor
Lead break, cylinder
temperature sensor F6
Lead break, Vitosolic cyl-
inder temperature sen-
sor
Short circuit, buffer cylin-
der temperature sensor
Short circuit, external
heat source temperature
sensor
Lead break, buffer cylin-
der temperature sensor
Troubleshooting
Measures
Check sensor and replace
if required (see Vitosolic
installation and service
instructions).
Check resistance (Pt 500)
at plug-in connection F6
and terminals X6.2/X6.1;
replace sensor if
required.
Check sensor and replace
if required (see Vitosolic
installation and service
instructions).
Check resistance (Pt 500)
at plug-in connection F4
and terminals X5.6/X5.7;
replace sensor if
required.
Check pressure drop
value (Pt 500) at plug-in
connection F20 and termi-
nals X6.8/X6.9; replace
sensor if required.
Check resistance (Pt 500)
at plug-in connection F4
and terminals X5.6/X5.7;
replace sensor if
required.
133