10
Troubleshooting
Logano plus GB402 - Subject to technical modifications!
60
V
4Y
523
Boiler
temperature
sensor break.
Temperature too
low at the boiler
temperature
sensor
(< -5 °C)
Check the sensor lead.
Replace in case of
damage.
Check the plug-in
connection.
Clean or replace if
contaminated.
Replace in case of
damage.
Refit plug it is found to
be loose.
Check sensor values
according to table.
Replace the
temperature sensor in
case of deviations.
Check the voltage at the
temperature sensor
according to table (SAFe
documentation).
Replace the SAFe in
case of deviations.
V
4U
524
Boiler sensor
short circuit.
The boiler sensor
detected an
excessively high
temperature
(> 130 °C).
Check the sensor lead.
Replace in case of
damage.
Check the plug-in
connection.
Clean or replace if
contaminated.
Replace in case of
damage.
Refit plug it is found to
be loose.
Check sensor values
according to table.
Replace the
temperature sensor in
case of deviations.
Check the voltage at the
temperature sensor
according to table (SAFe
documentation).
Replace the SAFe in
case of deviations.
V
4A
575
Intelligent high
limit safety
cut-out
responds.
The boiler flow
temperature has
reached its
maximum
permissible level.
The high limit safety cut-out
has responded.
Check gas valve.
(Does the flame
extinguish after a control
shutdown?)
B
5L
542
Incomplete
communication
with the SAFe.
The MC10
generates this fault
if not all required
data is supplied by
the SAFe.
Check the cabling between
the SAFe and the MC10.
Replace the SAFe if the
connections are OK.
Type
1)
Display
code
Fault
code
Cause
Description
Test procedure/cause
Action
Tab. 21 Fault displays
1) V = interlocking; B = blocking
