10
Troubleshooting
Logano plus GB312 - Technical specifications are subject to change without prior notice
74
BC
OE
-
The appliance is
in standby mode,
heat demand is
present but too
much heat is
being delivered.
The current heat
demand from the
system is lower than
that supplied by the
minimum burner
modulation setting.
-
-
BC
OU
-
Beginning of
sequence for
starting up
burner.
-
-
-
BC
OC
-
Beginning of
burner start-up.
-
-
-
BC
OL
-
Gas valve open-
ing.
-
-
-
BC
OF
-
Lack of flow
through boiler.
Temperature differ-
ence between supply
and return > 27 °F,
> 15 K.
Temperature differ-
ence between supply
and high limit tem-
perature sensor
> 27 °F, 15 K.
Check supply temp.
with BC10,
Check return temp.
with RC35 or S-Key,
Check resistance of
high limit sensor.
Adjust setting of
boiler pump.
Check surface temp.
of cast section with
mounted high limit
sensor with temp.
meter.
Check if cast section
is blocked with dirt.
Type
1)
Display
code
Event
code
Cause
Description
Testing sequence/
Cause
Action
Tab. 16 Operating codes1) V = locking; B = inhibiting; BC = operating code
