Buderus Logano plus GB312 Installation Manual page 74

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