Operating instructions

55
Message
System characteristics Cause Measures
9A Collector sensor
Collector temperature
sensor lead broken
Check resistance (Pt 500)
at plug-in connection F21
and terminals X6.10/
X6.11; replace sensor if
required.
If the Vitosolic is connec-
ted, check the Vitosolic
sensor (see Vitosolic
service instructions).
9B Return sensor solar
Return temperature sen-
sor lead broken,
Check resistance (Pt 500)
at plug-in connection F18
and terminals X6.6/X6.7;
replace sensor if
required.
If the Vitosolic is connec-
ted, check the Vitosolic
sensor (see Vitosolic
service instructions).
A4 Check valve
Solar check valve stuck
or faulty
Check the check valve
and replace, if required.
A6 Secondary pump
No flow in secondary cir-
cuit (secondary circuit
pump stopped)
Check voltage at connec-
tion 211. 2 and check sec-
ondary pump mechani-
cally; replace if required.
A7 Solar circuit
No flow in solar circuit
(solar circuit pump stop-
ped)
Check voltage at connec-
tion 212.4 and check solar
circuit pump; replace if
required (see Vitosolic
installation and service
instructions).
A8 Pump heating circuit 1
No flow in heating circuit
A1 (circuit pump stop-
ped)
Test voltage at connection
212.2 and check pump
mechanically; replace if
required.
Troubleshooting
Messages
(cont.)
5441 603 GB
Service