Viessmann VITODENS 200 Start-Up And Service Instructions page 35

Cause of fault
Internal fault burner control unit or interference
Safety chain was activated (fixed high limit)
Fan speed too high at start (maximum fan rpm exceeded).
Fan speed too low at start (incorrect fan rpm).
Air pressure threshold for ignition level is not reached.
Feedback voltage signal to LGM 29 not available.
Fan speed incorrect.
Fan speed too high prior to ignition (incorrect fan rpm).
Fault fan speed
No flame signal
Basic level of air pressure threshold in standby mode not
correct.
Severe wind conditions in vent system.
Flame signal still present after switching off.
Reset button "EU" pressed repeatedly or while burner is
running.
Corrective action
Check electrode settings.
Check wiring harness plug X13 for proper connection or
damage.
Check whether flue gas system is leak-tight.
If after corrective action fault "FE" still appears on display
replace LGM 29.
Check fixed high limit (see page 43). Bleed air from the
heating system.
Fan or fan electronics defective.
Replace RLS 154 electric fan control.
Replace LGM 29 and/or burner assembly.
Check fan and flue gas system.
Check fan plug, fan, differential pressure sensor (see page 41)
and inlet air damper (flapper).
Check flue gas system for proper sizing and functioning.
Check fan and flue gas system.
Check fan and flue gas system.
Check fan and flue gas system.
Check electrical connections (see page 11).
Purge air from gas line (for LP gas, purge air several times).
Measure ionization current (see page 24).
Check gas pressure (see page 13).
Check gas combination valve (see page 13).
Check ignition transformer.
Check ignition electrodes (see page 20).
Check condensate drain (see page 20).
Check power supply polarity (L,N,G).
Check proper grounding.
Check #158 plug on (replacement) LGM 29 is installed
Check differential air pressure sensor (see page 41).
Check wiring harness and connection to air pressure sensor.
Protect outside wall vent termination from severe winds.
Check gas combination valve (see page 13).
Check electrode block (see page 20).
Power ON/OFF boiler / acknowledge fault.
Press reset button "EU" once.
Troubleshooting
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