63
Displayed fault
code
System characteristics
Cause
Measures
349
Burner in a fault state
Air mass rate flow not de-
tected correctly in fan unit.
■
Check for dust contamination in
the ventilation air.
■
Check burner gauze assembly
for contamination.
Reset the appliance. If the fault oc-
curs repeatedly, replace the gas
fan unit.
350, 351
Burner in a fault state
Ionisation current lies out-
side the permissible range
Replace the HBMU heat manage-
ment unit. See chapter "Replacing
the HBMU heat management unit".
352
Burner in a fault state
Combustion CO limit ex-
ceeded
Check entire flue gas path for the
following:
■
Leaks
■
Flue gas back pressure caused
by water pocket (if flue system
fall is insufficient)
■
Constrictions
■
Blockages
Repair flue system if necessary.
Reset the appliance.
353
Shutdown with restart if de-
mand exists
Insufficient gas supply,
burner output reduced
Check the gas supply.
Visually check the inlet strainer in
the gas solenoid valve for dirt.
Reset the appliance.
354
Burner in a fault state
Gas modulation valve tol-
erance outside permissi-
ble range
Replace gas fan unit.
355
Burner in a fault state
Analogue signal reference
check: Flame signal is al-
ready present at burner
start.
Replace the HBMU heat manage-
ment unit. See chapter "Replacing
the HBMU heat management unit".
357
Burner in a fault state
Insufficient gas supply
■
Check that the main gas valve
and the gas shut-off valve are
open.
■
Test static gas pressure and gas
flow pressure.
■
Check that on-site gas line and
gas flow switch are correctly
sized.
Note
If the building pressure regulator
has a leak, you may notice rising
pressure when the burner is idle.
When the system is restarted,
the gas flow switch may trip.
■
If the static pressure doesn't
drop, check cable to the fan unit.
Check that the coil resistance at
the fuel valve is approx. 4 k
Ω
(plug 35).
■
Check the ignition electrode for
damaged insulation.
Reset the appliance.
Troubleshooting
Fault messages
(cont.)
6173886
Diagnosis
Содержание B0KA
Страница 14: ...14 1 4 5 3 2 Fig 4 Installation sequence Removing the boiler from the packaging 6173886 Installation ...
Страница 28: ...28 1 2 Fig 20 Installation sequence Fitting the front panel 6173886 Installation ...
Страница 78: ...78 1 2 3 6 4 5 7 Fig 42 Troubleshooting Repairs cont 6173886 Diagnosis ...