2Fault Displays - Buderus Logano plus GB402 Installation And Maintenance Instructions Manual

Supple-
Display mentary
code code Cause
OL - Opening the gas
valve.
OF - Insufficient boiler
flow rate.
Tab. 20 Operating codes
10.2.2 Fault displays
Display Fault
1)
Type code code
B 2E 207
V 2U 533
B 2U 565
V 2U 575
Tab. 21 Fault displays
1) V = interlocking; B = blocking
Logano plus GB402 - Subject to technical modifications!
Description
-
Temperature differential
between the flow and
return > 15 K.
Temperature differential
between flow and safety
temperature sensor
> 15 K.
Cause Description
Water -
pressure
< 0.6 bar.
Incorrect The boiler control
hydraulic unit has
connection of recognised an
boiler or incorrect flow on
pump. the water side.
Excessive Heat exchanger
differential protection due to
between the excessive
flow and temperature
return spread.
temperature.
> 40 K
Intelligent high The actual boiler
limit safety flow temperature
cut-out, flow. reaches the
intelligent high limit
safety temperature
for the flow of
140 °C, and a
flame current is
detected or the
solenoid valves are
open.
Test procedure/
cause
-
Check the flow
temperature on the
BC10, check the
return temperature
with RC35 or the
service key, measure
the resistance of the
boiler sensor (high
limit safety cut-out)
and compare with the
curve.
Test procedure/cause
Check whether the heating
system pressure is at least
1 bar.
Check that the boiler flow
and return have not been
swapped.
Check pump for correct
flow direction.
Problems with the
hydraulics.
Check the flow rate on the
water side.
10
Troubleshooting
Action
-
Adjust the setting of the
boiler circuit pump.
Check the surface
temperature of the cast
section that is equipped
with the safety
temperature sensor using
a thermometer.
Check whether a cast
section is blocked with
dirt.
Action
Correct the operating
pressure.
Connect flow and return
correctly.
Ensure correct pump
flow direction.
Check the system
hydraulics.
Ensure adequate flow
rate.
Replace boiler sensor/
high limit safety cut-out.
Replace ignition/
monitoring electrode.
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