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Deactivation of auxiliary heating > < Activation of auxiliary heating

A5

Auxiliary heater heating mode
   
Auxiliary heater heating mode
No.Operating sequence
1Full load heating mode (maximum heat output)
 
l  Coolant temperature in heater less than 77 °C.
l  No deviations in measured values and components monitored → Chapter.
l  Resistance of flame monitor -G64- in specified range.
  
–  Combustion air blower -V6- set to full load.
–  Clock frequency of metering pump -V54- set to full load.
–  Checking of flame formation by flame monitor -G64-.
  Components Actuation
with		Duration
approx.
  Combustion air blower -V6- (regulated).approx. 9 VUntil coolant temperature in heater reaches 77 °C.
  Metering pump -V54- (regulated).approx. 8 HzUntil coolant temperature in heater reaches 77 °C.
  Glow plug for heater -Q9-.0 V-
 
l  Coolant temperature in heater remains below 77 °C.
  
–  Heater remains in full load mode until switch-off.
 
l  Coolant temperature in heater reaches 77 °C.
  
–  Switching from full load to part load mode (coolant temperature in heater reaches 77 °C).
 Possible deviations in full load heating mode (maximum heat output)
 
l  Voltage drops below specified shutoff voltage.
–  Burn-off (entry in event recorder)/fault/off.
 
l  Flame goes out.
–  Burn-off and re-start.
2Part load operation (approx. 50 % of heat output)
 2.1Part load mode (diesel)
  Switching from full load to part load mode (approx. 50 % of heat output):
l  The coolant temperature in the heater increases and reaches 77 °C.
l  No deviations in measured values and components monitored → Chapter.
l  Resistance of flame monitor -G64- in specified range.
  
–  Reduction in voltage at combustion air blower -V6-.
–  Reduction in clock frequency of metering pump -V54-.
–  Checking of flame formation by flame monitor -G64-.
–  Actuation of heater coolant shut-off valve -N279-, governed by temperature → Chapter
  Components Actuation
with		Duration
approx.
  Combustion air blower -V6- (regulated).From approx. 9 V
to
approx. 6 V		5 sec.
  Metering pump -V54- (regulated).approx. 4 Hz5 sec.
  Glow plug for heater -Q9-.0 V-
  
–  Combustion air blower -V6- set to part load.
–  Clock frequency of metering pump -V54- set to part load.
–  Checking of flame formation by flame monitor -G64-.
  Components Actuation
with		Duration
approx.
  Combustion air blower -V6- (regulated).approx. 6 VUntil the coolant temperature in the heater drops below 60 °C or reaches
89 °C
  Metering pump -V54- (regulated).approx. 4 HzUntil the coolant temperature in the heater drops below 60 °C or reaches
89 °C
  Glow plug for heater -Q9-.0 V-
 
l  Coolant temperature in heater reaches 89 °C.
  
–  Switching from part load mode to control interval.
 
l  Coolant temperature in heater drops below 60 °C.
  
–  Switching from part load to full load mode.
 
l  Coolant temperature in heater remains between 60 °C and 89 °C.
  
–  Heater remains in full load mode until switch-off.
 2.2Part load mode (petrol)
  Switching from full load to part load mode (approx. 50 % of heat output):
l  The coolant temperature in the heater increases and reaches 77 °C.
l  No deviations in measured values and components monitored → Chapter.
l  Resistance of flame monitor -G64- in specified range.
  
–  Reduction in voltage at combustion air blower -V6-.
–  Reduction in clock frequency of metering pump -V54-.
–  Checking of flame formation by flame monitor -G64-.
–  Actuation of heater coolant shut-off valve -N279-, governed by temperature → Chapter
  Components Actuation
with		Duration
approx.
  Combustion air blower -V6- (regulated).From approx. 9 V
to
5 V		5 sec.
  Metering pump -V54- (regulated).approx. 2 Hz5 sec.
  Glow plug for heater -Q9-.0 V-
  
–  Combustion air blower -V6- set to part load.
–  Clock frequency of metering pump -V54- set to part load.
–  Checking of flame formation by flame monitor -G64-.
  Components Actuation
with		Duration
approx.
  Combustion air blower -V6- (regulated).5 VUntil the coolant temperature in the heater drops below 60 °C or reaches
89 °C.
  Metering pump -V54- (regulated).2 HzUntil the coolant temperature in the heater drops below 60 °C or reaches
89 °C.
  Glow plug for heater -Q9-.0 V-
 
l  Coolant temperature in heater reaches 89 °C.
  
–  Switching from part load mode to control interval.
 
l  Coolant temperature in heater drops below 60 °C.
  
–  Switching from part load to full load mode.
 
l  Coolant temperature in heater remains between 60 °C and 89 °C.
  
–  Heater remains in full load mode until switch-off.
3Control interval
 
l  The coolant temperature in the heater increases and reaches 89 °C.
l  No deviations in measured values and components monitored → Chapter.
l  Resistance of flame monitor -G64- in specified range.
  
–  No regulation of combustion air blower -V6-.
–  No regulation of metering pump -V54-.
–  No regulation of glow plug for heater -Q9-.
  Components Actuation
with		Duration
approx.
  Combustion air blower -V6-.0 V-
  Metering pump -V54-.0 Hz-
  Glow plug for heater -Q9-.0 V-
 
l  Coolant temperature in heater remains above 65 °C.
–  Heater remains in control interval until switch-off.
 
l  Coolant temperature in heater drops below 65 °C.
–  Starting from control interval → Chapter.

  Note
On starting from the control interval, the times for the various procedures differ from those on re-starting, as the heater is already at operating temperature (e.g. pre-heating for 20 instead of 35 s, fuel delivery for 30 instead of 56 s).
   

Deactivation of auxiliary heating > < Activation of auxiliary heating