4.1 Boiler accessories
Flue gas recirculation
For part no., see pricelist
Standard delivery:
■ Inlet line made from heat-resistant steel, from flue outlet to inlet
adaptor
■ Inlet adaptor, ventilation air, with motorised cover
■ Recirculation fan in heat-resistant design
■ Supply line for gas mixture incl. dampers to the combustion block
(internal and external grates)
■ Software module in the controller
Note
Thermally insulating
the
flue gas recirculation line
is the respon-
sibility of the customer as part of the general thermal insulation work
on flue gas and heating pipes.
Displacer rods
For part no., see pricelist
Installation of the displacer rods in the heat exchangers results in
better heat transfer and therefore a considerable reduction in flue
gas temperature. We only recommend their use when particularly
low flue gas temperatures are required and when used as a base
load boiler.
Note
In 390 and 530 kW boilers, DN 40 boiler pipes are used. As a result,
the flow velocity of the flue gas is higher and there is no need for dis-
placer rods in these boilers.
Automatic ignition system
For part no., see pricelist
The heating element is electronically protected against overload,
eliminating the need for visual heating element monitoring. The heat-
ing element reliably achieves the specified maximum temperatures.
Function:
If the combustion chamber is filled accordingly with fuel, the ignition
process is triggered.
The fuel is ignited with hot air. If ignition is successful, the ignition
system switches off.
The fan of the ignition system runs on for approx. 1 minute. This
cools the heating element and supplies the combustion chamber
with outdoor air.
Specification
Ignition system
Operating voltage
V/Hz
230/50
Pressure
Pa
2800
Weight
kg
1.1
Length
mm
335
Width
mm
85
Height
mm
85
Flame tube diameter
mm
31.5
Max. temperature
°C
650
Length of power cable
mm
2000
Connected load
kW
1.4
Note
Automatic ignition only functions up to a max. fuel moisture content
of M40.
Pneumatic cleaning
For part no., see pricelist
The whole tubular heat exchanger is cleaned with periodic blasts of
compressed air during operation. The process of cleaning itself is
carried out in consecutive blasting of the individual sections with
compressed air. Ash is removed from the heat exchanger pipes by
means of a very short but extremely intensive pressure pulse. The
loosened particles are carried in the gas flow to the dust extractor,
where they are separated out.
The device is integrated in the boiler door.
The number of cleaning processes within a unit of time (e.g. per
hour) is matched to the boiler load. An individual, complete cleaning
process comprises a sequence of pressure pulses across all sec-
tions of the heat exchanger.
Standard delivery:
■ Nozzle part integrated in the boiler door, incl. connectors with heat
dissipation discs
■ Compressed air distributor with container and valves, connected to
the nozzle part with heat-resistant hoses
■ Compressor (rotation compressor) for municipal applications, incl.
pressure regulator and pressure switch
■ Compressed air hose up to max. 4.0 m in length
■ Valves fully wired on terminal strip
■ Software module in the controller
■ Output terminals in control panel for power supply to the compres-
sor (rotation compressor)
To be carried out by the customer:
■ Provision of a socket 400 V / 16 A
■ Connector for compressor 400 V / 16 A
Compressor specification
Supply output
l/min
160
Cylinder
l
90
Max. pressure
bar
10
MPa
1
Output
kW
1.5
Speed
rpm
1450
Voltage
V
3 x 400
Sound level
dB(A)
64
Specification
Rated heating output
kW
390
530
720
950
1250
Number of valves
pce
8
8
10
12
12
Size of valves
6/4”
6/4”
6/4”
6/4”
6/4”
Installation accessories
26
Viesmann
VITOFLEX 300-UF
4
5682428