Unical AIREX 25 2S, Installation And Servicing Manual

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8
Technical features and dimensions
3
8
11
1 2 14 13
17
12
15
18
M
R
9 10
16
4
6
5
F
F
7
2.3 - MAIN COMPONENTS
1. Instrument panel
2. Top cover
3
N°2 side p anels
4. Door on hinges anti-smoke
5. Wood storage door with
refractory ,and seal .
6. Central door with gasket, locking screws,
primary and secondary air
7. Fan ( n°2 fan for the model AIREX 65 2S and
AIREX 80 2S)
8. Door combustion chamber with seal,
refractory, light inspection
9. Combustion chamber made of thick steel
10. Flap of heat exchange
11. Boiler drain
12. Safety heat exchanger
13. By-pass with rod
14. Boiler mineral wool insulation
15. Steel shell boiler
16. Burner in refractory with blanks and grid
17. Smoke chamber
18. The
rmostatic valve
M Heating plant flow
R Heating plant backflow
fig. 2
N.B.:
The fire bars and the refractory steel grate are subject to wear; it is therefore advisable
to carry out an annual inspection to prevent bad boiler operation.
2.4 - GENERAL INFORMATION:
REVERSED FLAME COMBUSTION
Every body knows that to make a match last it must be held
with its head upwards.
This is because it is necessary that the flame, in its convective
motion, does not meet another fuel in addition to the one which
it has generated it. As in residential heating the fuel is in form
of wood logs which are loaded from the top, the flame has to
go in the opposite way, i.e. downwards.
Natural draught is a very variable source of depression,
according to the type of chimney, on the weather conditions,
on the type of fuel, etc.
Therefore it is necessary to integrate it with forced ventilation
in order to stabilize it.
By fitting a fan it is possible to considerably reduce the section
of the gas passages on the grate and furthermore there are no
problems with cold starts.
The small grate permits a more controlled passage of
combustion air, contrarily to what happens with the large
traditional grates.
The air can be perfectly dosed because the grate covered with
fired wood has the same crossing resistance and thus the
combustion will be always optimal.
Unical has already used this principal for many years with the
GASOGEN G3 2S boiler.
The AIREX 2S boiler today has reached such a high level of
perfection that it can pass all the most stringent tests foreseen
by the European Standards in force concer ning the
environment.