Buderus Logano plus GB402 Installation And Maintenance Instructions Manual page 50

10 Troubleshooting
Display
1)
Type code Fault code
V CY 573
V CY 574
V LP 570
Tab. 22 Fault displays
1) V = locking; B = blocking
50
Cause Description
Flow temperature The control unit
receives unrealistic
< -5 °C
values from the flow
(interruption)
temperature sensor.
Flow temperature The control unit
receives unrealistic
> 130 °C (short
values from the flow
circuit)
temperature sensor.
Too many resets Too many resets were
via the interface. carried out via the
interface within a
certain period.
Please note: this fault
can only be reset via
the button on the SAFe.
Test procedure/cause
Check cabling between SAFe and
flow temperature sensor.
Check electrical connection of the
SAFe cable.
Check resistance values of
temperature sensor according to
table.
Check voltage at the temperature
sensor terminals inside the SAFe
according to table.
Check cabling between SAFe and
flow temperature sensor.
Check electrical connection of the
SAFe cable.
Check resistance values of
temperature sensor according to
table.
Check voltage at the temperature
sensor terminals inside the SAFe
according to table.
Faults have been repeatedly reset
but not removed.
The BC10 has developed a fault
causing constant resets.
The SAFe has developed a fault.
Logano plus GB402 – 6 720 804 428 (2012/09)
Correction
Replace cable if required.
Remedy contact problem if
required.
Replace temperature sensor if
required.
Replace SAFe if resistance
values of the temperature
sensor are correct, but voltage
values are incorrect.
Replace cable if required.
Remedy contact problem if
required.
Replace temperature sensor if
required.
Replace SAFe if resistance
values of the temperature
sensor are correct, but voltage
values are incorrect.
Identify the cause for the faults
that have resulted in the resets
and remove them.
BC10 Replace.
Replace the SAFe.