Manual_S5_Airplus_2015_04_20
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Wodtke GmbH - Tübingen. All Rights and Changes Reserved.Printed 04/2015
Part No. 950 976
18.2 Overview of Class 2 Error & Fault Codes (Not Safety-Related)
Class 2 errors are of subordinate importance (not safety-related) and manual reset is not required
after resolving the cause of the fault. The automatically returns to normal operation after resolving
the cause of the fault.
Fault code
Class 2
Cause of fault
Target values
Resolution of fault
L- LO =
Air volume in intake pipe un-
derrun, L-LO indicator blinks in
alternation with the respective
programme indicator.
Measurement point: Air vol-
ume sensor in intake pipe [=
two resistors in bridge circuit,
one
resistor
continuously
heated. Cooling = function of
flow speed]
External error / operating error! Minimum air
volume in intake pipe underrun longer than
5 seconds.
This occurs due to opening of the combus-
tion chamber doors, for example
no air
through-put through the intake pipe
Another cause: if the air through-put through
the unit is no longer possible due to extreme
contamination of the heating gas flues / con-
nector or the resistance in the combustion
line is too high or the combustion air line is
closed/clogged.
L
>
2.0
Value is que-
ried continually
starting 1 mi-
nute after start.
After a restart,
the query also
does not hap-
pen until after
1 minute.
There is not a unit defect!
Close combustion chamber
door (if open) or find other
cause (e.g. access panel
open, door not sealed). Per-
form maintenance/cleaning
as required. Unit continues
to operated in the previous
programme after error is re-
solved.
Exception: Flue gas tem-
perature has dropped. Then
the indicator "TR" appears
see Cl. 1 error code
BU Er1 =
BUS error (RS 485 - interface)
BUS error on input "RS 485" with normal
shutdown HE OFF / G OFF / BU ER1. Bus
communication with external heating con-
troller disrupted for longer than 60 seconds
or external heating controller/gateway incor-
rectly connected/defective or RS 485 input
defective.
Error can only occur if the "BUS" input is
switched active (activation / deactivation via
menu level 2 - see Chapter 8.3.3).
Inspect BUS cabling (conti-
nuity, polarity, installation)
to
the
external
gate-
way/controller. Error is reset
automatically + furnace re-
started as soon as the BUS
connection is active again.
Attention:
with "BU Er1,"
the furnace can only be
manually operated if the
"BUS" input is deactivated
(activation / deactivation via
menu level 2 - see Chapter
8.3.3).
18.3 Internal Regulation Function "R.M"
This function is summarised here because it partially also serves for technical safety monitoring of the units and is
significantly influenced by external parameters. These are regulation functions - the units respond to external influ-
ences / operating parameters here.
Regulation function / dis-
play indicator
Cause
Target values
Resolution of fault
R.M =
Internal modulation
No error in an actual sense
(regulation function)
Case A:
Value for flue gas temperature TR
was exceeded, the unit switches back to
lowest load until the values are met. This is
a regulation function (not a defect), which
can be triggered by operating with pellets
with a high heating value (average output
of the unit is over the rated heating output
as a result).
Case B:
The temperature on the air volume
sensor was exceeded. The furnace regu-
lates to the lowest output. Once the tem-
perature lowers sufficiently, the furnace re-
turns to the previously adjusted output.
This is a regulation function (not a defect)
which can be triggered by the combustion
air temperature being too high, for exam-
ple.
TR
max
< 999 °C
with hysteresis
6 C
T
L
< 90 °C
There is an automatic return
from modulation "R.M" to the
preset output as soon as the de-
vice values have lowered by the
cited hysteresis.
