Viessmann VITOCROSSAL 200 Service Instructions Manual page 45

Diagnosis
(cont.)
Faults without fault display
Fault
Combustion fault
through pulsation
Burner restarts and
switches off after the
safety time has
expired
CO is formed or burner
is very sooty
CO content too low
2
Excessive flue gas
temperature
Whining noises
Cause
Excessive gas
throughput
Too little or too much
air
Condensate banked
up in flue system
Incorrect flue outlet
Cores "L1" and "N" at
the power supply ter-
minals of the control
unit interchanged
Too little or too much
air
Insufficient draught in
flue system
Incorrect setting
Excessive gas
throughput
Incorrect CO set-
2
tings
Measure
Adjust gas throughput in accord-
ance with rated boiler heating out-
put.
Adjust gas throughput in accord-
ance with rated boiler heating out-
put.
Check condensate drain.
Check flue outlet.
Check the power supply and swap
the cores.
Adjust correctly. Check ventilation of
installation room.
Check flue system.
Check that burner has been adjus-
ted for the correct gas type, and
change gas restrictor if required
(see from page 9).
Adjust burner in accordance with the
details from page 14 .
Adjust gas throughput in accord-
ance with rated boiler heating output
(see supply values, page 66).
Check condition of secondary heat-
ing surfaces of the boiler, and clean
if required.
Adjust burner in accordance with the
details from page 14 .
Troubleshooting
45