35
Fault code
*1
Shown on
display
System characteristics
Cause of fault
Measure
F 4b
F 4b
Parameter memory stick
not found
Parameter set enabled,
but memory stick not
plugged into burner con-
trol unit; memory stick
faulty
Plug memory stick into
burner control unit; re-
place memory stick.
F 4c
None
Parameter memory stick
matching
Parameters could not be
transferred from memory
stick.
Replace memory stick or
burner control unit.
F 4d
F 4d
Incorrect password for
parameter memory stick
Invalid password entered
for memory stick
Check password and
memory stick. See instal-
lation instructions for
burner components.
F 4F
F 4F
Type of parameter mem-
ory stick
Memory stick does not
match burner control
unit.
Replace memory stick or
burner control unit.
I
Danger
Plug-in terminals on
the burner control
unit are live.
Only replace memory
stick when burner
control unit has been
isolated from power
supply.
F 40
None
Burner control unit in a
fault state
Incorrect set default val-
ue for fan in parameter
set
Replace memory stick.
I
Danger
Plug-in terminals on
the burner control
unit are live.
Only replace memory
stick when burner
control unit has been
isolated from power
supply.
F 41
F 41
Fan speed deviation
Fan faulty; cable "100A"
faulty or broken; fan un-
suitable for the required
speed
Check the cable and re-
place cable "100A" or fan
if required.
F 42
F 42
No feedback from fan
Fan faulty; external pow-
er supply to fan not con-
nected or faulty; cable
"100A" faulty or broken;
fan blocked (poss. by a
foreign body)
Check cable "100A";
check external power
supply; replace cable or
fan; remove foreign body.
F 43
F 43
Burner control unit in a
fault state
Internal fault of the burn-
er control unit and during
test of ionisation input
Replace burner control
unit.
F 50
F 50
Burner control unit in a
fault state
Internal fault in servomo-
tor feedback; output re-
lay does not respond.
Replace burner control
unit.
F 53
9
Gas shortage at gas
pressure switch; valve
leak test
Gas valve does not
open; gas valve leaking
Replace gas train.
After replacing the gas
train, extended reset (see
page 34)
*1
All fault codes are saved to the fault memory and the last 10 can be called up.
Troubleshooting
Diagnosis
(cont.)
5783 337 GB
Diagnosis