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Building Technologies Division    CC1N7451en 
  20.11.2017 
Function (cont'd) 
-  Burner control must be reset 
-  Sequence switch must be in its start position  voltage at terminals 4 and 11 present 
- Air damper closed 
-  End switch «z» for the «CLOSED» position must feed voltage from terminal 11 to 
terminal 8 
-  The contacts of control thermostat or pressurestat «W» and other contacts of 
switching devices connected between terminal 12 and «LP» must be closed 
 e.g. 
control contact for the oil preheater’s temperature 
-  Terminal 4 must be live 
-  The N.C. contact of the air pressure switch must be closed  «LP» test 
Preconditions for burner 
startup