Operating instructions

32
Display screen Measures
Control unit issues
a heat demand
no
Increase set value
and ensure heat is
drawn off
yes
Fan starts
no
after approx. 51 s
fault F9
Check the fan, fan
connecting cables,
power at the fan
and fan control
yes
Ignition
no
Fault F4 Check the connec-
tion ignition mod-
ule
yes
Gas train opens
no
Fault F4 Check the gas
train (control volt-
age 230 V); check
the gas supply
pressure
yes
Ionisation current
builds (higher than
2 µA)
Symbol
A
no
Fault F4 Check the ionisa-
tion current, check
the electrode
adjustment and
the gas pipe for air-
locks.
Troubleshooting
Function sequence and possible faults
5366 836 GB