Viessmann Vitodens 200-W B2HE Installation And Service Instructions Manual page 84

Troubleshooting
Fault messages
(cont.)
Fault number System characteristics
on the display
F.352 Burner in a fault state
F.353 Burner blocked
F.354 Burner in a fault state
F.355 Burner in a fault state
F.357 Burner in a fault state
84
Cause
CO limit within appliance
exceeded
Insufficient gas supply,
burner output reduced
Gas modulation valve tol-
erance outside permissi-
ble range
Analogue signal reference
check: Flame signal is al-
ready present at burner
start.
Insufficient gas supply
Measures
Check entire flue gas path for the
following:
Flue gas recirculation
■
Leaks
■
Flue gas back pressure caused
■
by water pocket (if flue system
fall is insufficient)
Constrictions
■
Blockages
■
Repair flue system if necessary.
Reset device.
Check the gas supply.
Optically check input-side screen
in the gas train for contamination.
Reset device.
Check connecting cables to the
gas train for damage.
Check gas train.
Check the flue system for block-
ages or constrictions.
Reset device.
Check system for condensate
backup.
Note
To prevent water damage, detach
fan unit before removing the burn-
er.
Reset device.
Check that the gas shut-off valve is
open.
Optically check input-side screen
in the gas train for contamination.
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.
Reset device.