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Building Technologies Division  Basic Documentation LME39…  CC1P7106en 
 7 Functions  08.12.2017 
7.4  Control sequence in the event of fault 
 
If lockout occurs, the outputs for the fuel valves, the burner motor and the ignition 
equipment immediately deactivated (<1 second). 
 
Cause  Response 
Mains failure  Safety shutdown, followed by restart on restoration of mains 
voltage 
Voltage below undervoltage threshold  Safety shutdown 
Voltage above undervoltage threshold  Restart 
Extraneous light during prepurge time   Lockout, blink code 4 
Extraneous light during waiting time   Prevention of startup, lockout after approx. 30 seconds at 
the 
latest, blink code 4 
No flame at the end of safety time  
Factory setting: 
Lockout at the end of safety time, blink code 2 
 
Can be parameterized: 
Max. 3 repetitions, followed by lockout at the end of safety 
time, blink code 2 
Loss of flame during operation 
Factory setting: 
Lockout, blink code 7 
 
Can be parameterized: 
Max. 3 repetitions, followed by lockout, blink code 7 
Air pressure switch welded in working position  Prevention of startup, lockout after approx. 65 seconds at 
the latest, blink code 5 
Air pressure switch welded in no-load position 
- Failure during valve proving  
  (only in connection with LDU11...) 
Lockout approx. 180 seconds at the end of specified time 
blink code 3 
 
Note! 
Time may be extended by the actuator’s running ti
(t11), depending on the application. 
No air pressure signal after completion specified time  Lockout, blink code 3 
CPI contact is open during waiting time  Prevention of startup, lockout after approx. 60 seconds at 
the 
latest, blink code 14 
Table 5: Lockout 
 
In the event of lockout, the LME39… remains locked and the red fault signal lamp lights 
up. The burner control can immediately be reset. This state is also maintained in the 
event of mains failure. 
 
7.5  Resetting the burner control 
 
When lockout occurs, the burner control can immediately be reset. Keep the lockout 
reset button depressed for about 1 second (<3 seconds). The LME39… can only be 
reset when all contacts in the line are closed and when there is no undervoltage. 
 
The burner control can also be reset via display and operation unit AZL2... or PC 
software ACS410.