Fault Messages - Buderus LOGANO PLUS GB312 Installation Instructions Manual

10
Troubleshooting
Display Event
1)
Type code code
BC OF -
Table 21 Operating codes 1) V = locking; B = inhibiting; BC = operating code

10.2.2 Fault messages

Display
1)
Type code Fault code
K 2E 207
K 2U 565
V 2U 575
V 3C 537
V 3C 538
V 3C 540
Table 22 Fault messages
1) V = locking; B = inhibiting; BC = operating code
54
Cause Description
Lack of flow through Temperature difference
boiler. between supply and return
> 27 °F, > 15 K.
Temperature difference
between supply and high
limit temperature sensor
> 27 °F, 15 K.
Cause
The water pressure is < 8.7
psi (0.6 bar).
Difference between supply
and return temperature too
great.
(>72 °F; >40 K)
Boiler sensor/
ISTB sensor.
No speed signal.
Fan speed too slow.
Fan speed too fast.
Test procedure/cause
Check supply temp. with
BC10, Check return temp.
with RC35 or S-Key, Check
resistance of high limit sensor.
Testing sequence/
Description Cause
- Is system pressure
at least 14.5 psi
(1 bar)?
Heat exchanger cut-out System configuration
due to excessive problems.
temperature spread.
The maximum Check water flow.
permissible temperature
at the ISTB has been
reached.
The SAFe is not receiving Check connecting leads
a speed signal even between SAFe and fan for
though the fan is poor contact, breaks and
supposed to be running. damage.
Check connectors on
SAFe and fan.
The actual speed Dirt in fan.
detected is slower than
Fan defective.
the set speed.
The actual speed Check PWM signal/SAFe
detected is faster than connecting lead for poor
the set speed. contact, breaks and
damage.
Check connectors for
damage.
Measure
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.
Measure
Adjust operating
pressure.
Check system
configuration.
Check water flow.
Check non-return valve
direction
of flow.
Check boiler sensor/
STB.
Establish good electrical
contact. Replace lead if
necessary.
If fan has power (but is
not running) replace fan.
If fan has no power,
replace the SAFe
Clean fan if necessary.
Replace fan.
Establish good electrical
contact. Replace lead if
necessary.
Replace fan.
Logano plus GB312 – 6 720 647 367 (2012/11)