10
Troubleshooting
Logano plus GB312 - Technical specifications are subject to change without prior notice
73
10.2 Operating and fault messages
10.2.1 Operating messages
Type
1)
Display
code
Event
code
Cause
Description
Testing sequence/
Cause
Action
2P
564
Boiler sensor
temperature gra-
dient too steep
( >126°F/min;
>70°K/min).
Heat exchanger cut-
out due to excessive
rate of temperature
rise.
Little or no heat draw
(e.g. thermostatic
valves and mixer
closed).
Boiler flow rate too
small.
Circulation pump not
working.
Circulation pump fit-
ted opposite way
round to intended
direction of flow.
Deposits in water car-
rying parts of boiler
(dirt from heating sys-
tem, limescale).
Ensure adequate
heat transfer.
Fit adequately
dimensed pumps.
Check whether pump
is being activated.
Replace pump if nec-
essary.
Fit pump correct way
round.
Flush/clean water
side of boiler heat
exchanger with
agents suitable and
approved for alumi-
num.
BC
OA
-
Appliance is in
optimized switch-
ing mode.
A new call for burner
operation has
occurred within the
optimized switching
period. Appliance is
in anti-cycle phase.
The standard opti-
mized switching
period is 10 min.
Check output setting
on BC10 basic con-
trol unit.
Check control setting
on RC35 program-
ming unit.
Adjust boiler output
to required heat
demand for building.
Adjust control setting
to system conditions.
BC
OH
-
The appliance is
in standby mode;
no heat demand
present.
The boiler is on
standby and there is
no call for heat from
the heating system.
-
-
BC
OY
-
The current boiler
water tempera-
ture is higher
than the set
boiler water tem-
perature.
The current boiler
water temperature is
higher than the set
boiler water tempera-
ture.
The boiler is shut
down.
-
-
BC
OP
-
Waiting for fan to
start up.
Start-up of the fan
has to be detected
before the sequence
can be continued.
-
-
Tab. 16 Operating codes1) V = locking; B = inhibiting; BC = operating code