Herz firematic CONDENSATION 30, Operating Instructions Manual

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Mode of operation 6
11
6 MODE OF OPERATION
6.1 Feeding system
The fuel is fed from the fuel storage room by the
room discharge system to the burn back
protection device (BFP). Fuel passes the hopper
first, afterwards the back burn flap. The back burn
flap gets steered by a spring loaded servo motor.
If the servo motor operates current less, the back
burn flap will close independently. Next the fuel is
fed towards the burning chamber by the feeding
screw. The achieved fuel level is a crucial factor of
the boiler heat output and operating mode.
6.2 Versions conveyor systems
6.2.1 Version flexible screw system
In this version, the fuel supply with flexible
discharge screw from the storage room. Attached
to the boiler is an insertion screw, which conveys
the pellets obliquely upwards and feeds them to
the combustion. The backfire protection device
(BFP) is located on this feed screw. This burn-
back protection device is opened by means of a
spring return motor. At standstill or power failure,
this engine closes automatically. The flap provides
a fireproof separation between the feed screw and
the discharge screw.
The BFP also requires level monitoring.
The flexible room discharge of the boiler consists
of a stored auger including cover in the storage
room area and a flexible auger in the area of the
boiler room. As drive a standard gear motor is
used.
The insertion screw is roughly made up of the
following components:
➢
Stoker screw motor
➢
Fire-resistant device with spring return
motor
➢
Stoker pipe
➢
Feed screw temperature sensor (PT 1000)
6.3 Feeding type
The operation of the boiler is based on a pulse-
no-pulse ratio, which controls the feeding system.
All the values are to be set via the menu “Fuel
values” (only available in the service area). These
feed values are corrected by the combustion
control system.
6.4 Combustion air control
The supplied combustion air is differentiated
between primary and secondary air. The primary
air is initiated directly into the embers. The
secondary air gets used to actuate the developed
flame to a completely. The air supply is piped via
vents on the burner side (underneath side cover).
The flue gas ventilator is a suction fan and this is
located at the back of the boiler. It generates low
pressure in the boiler. The secondary- and
primary air get sucked out due low pressure.
The ID-fan is time-controlled by the variable-
speed electronic control. The ID-fan speed is
controlled according to the boiler temperature and
rectified by the lambda control.
6.5 Boiler operation
The boiler starts up automatically with its built-in
automatic ignition, when heat is required.
The heat requirement can be controlled by the
weather or by a remote sensor (optional),
depending on any heating circuit. A room
thermometer can also be used to generate an
external requirement. The boiler can also be
started up by the requirement of a hot water tank.
The boiler output can be controlled by set up
values and adjusted to local conditions.
The boiler control prevents too low boiler
temperatures to avoid effect on the durability of
the system. Too high boiler temperatures are not
permissible.
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.
A pressure measurement is conducted
additionally after boiler has been operated with
the actual fuel for minimum 1 hour.
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,...).Then the chimney system must be
checked by a specialist.
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