Herz firematic PELLET 120 Operating Instructions Manual Download

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Mode of operation

Expansion cracks at insulating plates, respectively
burning chamber stones, don´t affect their
capacities and don´t represent warranty claim.

6.6

Commissioning

The commissioning must be carried out by HERZ
factory customer service or an authorised
specialist.

pressure

measurement

conducted

additionally after boiler has been operated with
the actual fuel for > 1 hour and a flow temperature
of 70-85 °C.

The  result  of  the  pressure  measurement
represents  a  characterisation  of  the  draught
during normal operation and shows, if the required
draught  has  been  reached.  If  a  deviation  occurs,
the  existing  chimney  has  not  been  dimensioned
correctly  or  dimensioning  underlying  installations
have  not  been  carried  out  correctly  (e.g.:  faulty
connections,  false  air  inflow,  too  long  connection
pipe,...) and the boiler does not operate properly.

During  initial  operation  and  commissioning  the
system  controls  and  safety  devices  must  be
checked and the handling of the boiler as well as
the  system  maintenance  schedule  must  be
explained to the operator.

The  hydraulic  balancing  of  the  equipment  (pipe
installation)  must  be  carried  out  by  an  authorised
specialist  company  (installer).  Zusätzlich  ist  der
Installateur verpflichtet (lt. Draft documentation for
all  the  equipment  (according  to  ÖNORM  EN
12170), which must be kept in the boiler room.

6.7

Operating and impermissible
temperatures

Boiler temperature

The  HERZ  firematic  boiler  operates  at  a  boiler
temperature  between  65  to  90  °C.  If  the  return
flow temperature is lower than 55 °C, flue gas will
condense  on  the  inside  of  the  boiler.  So  if  the
boiler  starts  up,  the  operating  temperature  (from
65  to  90  °C)  must  be  reached  as  quickly  as
possible in order to avoid condensation. The back
flow  temperature  may  also  be  lower  than  the
permissible  value  at  correct  boiler  operating
temperature. This condition should be avoided by
a back flow temperature increase.

Note!

All guarantee or warranty claims are invalidated in
the event of damage by corrosion arising due to
impermissible operation temperatures.

Back flow temperature

The back flow temperature is always lower than
the boiler temperature. The back flow temperature
must exceed 60 °C as quickly as possible,

depending  on  the  boiler  type.  Temperature  level
retention  of  the  back  flow  or  the  boiler
temperature  is  achieved  using  a  so-called  back
flow  bypass  or  back flow  temperature  monitoring.
In this case the flow is admixed via a pump and a
valve to the back flow.

The boiler´s heat energy can only be used after
the back flow temperature has exceeded 60 °C.

Too high boiler temperatures

The boiler can be operated with a maximum boiler
temperature  up  to  90  °C.  If  the  decrease  of
performance  drops  suddenly  (mixers  shut-off,  hot
water  tank  load  pump  switches  off)  the  boiler´s
saved heat energy can overheat the boiler.

The firematic boiler has three different pre-
installed safety devices to prohibit a further
temperature increase:

◼

Overheat temperature (higher than 92 °C
boiler temperature)

At this temperature the connected consumer

pumps  get  switched  on  in  order  to  conduct
overheat  (consumer  pump  connection  to  the
HERZ  controls  is  required).  Therefore  the
consumers  will  set  on  their  maximum  value.
Consumer  pump  connection  to  the  HERZ
controls  is  required.  If  the  consumer  pumps
aren´t  connected  to  the  HERZ  controls,  a
higher  probability  of  overheating,  resulting  in
failure, is given.

◼

Thermal valve for security heat exchanger:

The thermal valve must be connected to the

built in safety heat exchanger, according to
applied standards.

◼

Safety temperature limiter

– STL (over 95°C

boilertemperature)

At this temperature the boiler gets switched off.

The safety temperature limiter locks itself and
the boiler operation. A fault report gets
indicated, the boiler gets switched off.

Flue gas temperature

The flue gas temperature depends on the boiler
operation conditions, the fuel, the ventilator setting
and the boiler type.

Observe:
The  chimney  must  be insensitive  to  moisture  and
calculated  and  dimensioned  according  to  DIN
4705  or  EN  13384  .  HERZ  does  not  carry  out
chimney  calculations.  The  chimney  calculation
must  be  calculated  by  authorised  personnel.  A
miscalculated  or  undimensioned  chimney  may
lead to a malfunction of the system.