Herz BioFire 1000 Operating Instructions Manual Download

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Operating conditions

Thereafter, the system changes over to the scorch
phase,  where  at  the  same  time  the  final  ignition
fan  phase  is  carried  out.  During  the  final  ignition
fan  phase  the  ventilator  of  the  ignition  fans  runs
for  a  minute  longer  in  order  to  cool  down  the
heating element.

If ignition wasn´t possible prior the maximum
ignition period, the boiler will switch off and the
fault “IGNITION” will appear in the fault list.

Scorch phase

During the scorch phase the boiler control tries to
achieve an even fire bed. The length of the scorch
phase can be set in the fuel value settings (only
available in the service area). Pay attention to the
higher oxygen content at the combustion. During
the scorch phase the boiler control tries to achieve
an even fire bed.

Start up phase

During  the  start  up  phase  the  boiler  operates  at
nominal  heat  output.  If  the  boiler  set  temperature
is  reached,  the  boiler  will  switch  to  the  regulation
phase.

Regulation phase

During  the  regulation  phase  the  boiler  is
modulated between nominal load and partial load.
If  boiler  oversupplies  heat,  i.e.  if  the  boiler  target
temperature  +  control  hysteresis  gets  exceeded,
the  boiler  will  switch  to  the  operating  condition
„ready”.

Burn out phase

If  the  boiler  will  be  switched  off  the  remaining
quantity  of  residual  fuel  will  burn  independently.
Pay  attention to the  burn out phase time setup, if
chosen  too  short,  fuel  will  not  be  burned
accordingly.

Burner cleaning

During  the  burner  cleaning  phase  ash  gets
removed  off  the  grate.  The  boiler  switches  to  the
burn  out  phase  and  remaining  fuel  gets  burned
out.
Afterwards the grate gets cleaned and the boiler s
witches to normal operation.  Afterwards  the  grate
gets  cleaned  and  the  boiler  switches  to  normal
operation.  The  burner  cleaning  interval  is
calculated  by  the  feeding  screw  operating  time.
The cleaning interval is set up with the parameter
“ash discharge interval” in the service area.  So, if
the  grate  should  cleaning  frequently  you  have  to
reduce the parameter.

Heat exchanger cleaning

The  Heat  exchanger  gets  cleaned  automatically.
The cleaning interval and duration is set up in the
service  area  with  the  parameter  “heat  exchanger
cleaning  interval“  respectively  „heat  exchanger
cleaning duration“.

Boiler output control

The  output  control  is  controlled  within  the  boiler
target  temperature  and  the  control  end  phase.
The  control  end  phase  is  the  boiler  target
temperature  +  control  hysteresis.  If  the  regulation
end  is  reached,  the  boiler  will  switch  to  the  burn
out phase.

Flue gas temperature control

If the maximum flue gas temperature is exceeded,
the boiler output will be reduced. If the actual flue
gas temperature is lower than the maximum flue
gas temperature, the boiler will switch to normal
output control.

Flame

monitoring

(burning

chamber

temperature)

If the burning chamber temperature fluctuates
greatly during operation, the boiler will switch off.

Freezing protection

If  the  freezing  protection  operates,  the  back  flow
bypass  pump  will  switch  on  only  if  the  boiler  is  in
operating  mode  “HEATING  OFF”  or  “BURNER
STOP”.  Otherwise  (freezing  protection  disabled)
the  boiler  will  start  up  and  heat  up  to  minimum
boiler temperature 65 °C.

Lambda control

Over the lambda regulation was the amout of
material and the secondary air 1 + 2 ruled. The
control is able to detect marginal deviations of the
fuel

quality

and

induces

combustion

improvement.

Stoker screw - return:

Monitoring  the  motor  current  at  the  stoker  screw
motor.  When  the  insertion  screw  takes  to  much
current  was  the  turning  direction  of  the  insertion
screw  for  ca.  2  seconds  turned  to  loose  the
material  in  the  insertion  screw.  After  5  faulty  tries
was  the  equipment  turned  in  the  state  HEATING
OFF.