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Technical features and dimensions
2.3 - MAIN COMPONENTS
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 faulty boiler operation.
2.4 - GENERAL INFORMATION
REVERSED FLAME
COMBUSTION
Everybody 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 has generated it. As in residential heating the
fuel is in the 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 source of depression which varies greatly
depending on the type of chimney, on weather conditions, on
the type of fuel, etc.
Therefore it is necessary to integrate it with forced ventilation in
order to stabilise 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 large traditional grates.
The air can be perfectly dosed because the grate, covered with
burning wood, has the same crossing resistance and thus the
combustion will be always optimal.
1. Panel board
2. Top panel
3. Anti-smoke door fitted on hinges
4. Wood storage door with refractory material,
gasket and handle
5. Primary and secondary air adjustment units
6. Combustion chamber door with gasket,
refractory material and flame sight glass
7. Combustion chamber in thick steel
8. Catalyst in refractory material
9. Burner in refractory material with thermal steel grate
10. Steel boiler body
11. Bypass
12. Rear door for extraordinary cleaning
13. Smoke chamber inspection door
14. Smoke chamber
15. Safety heat exchanger
16. Flue gas intake fan
17. Smoke pipes cleaning system
18.Thermostatic valve system
19. Boiler body insulation in mineral wool
M C.H. flow
R C.H. return
VE Expansion vessel connection
Unical has already used this principal for many years with the
GASOGEN boiler.
The AIREX 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 concerning the environment.
2
1
3
4
6
5
7
9
10
11
16
14
12
15
13
R
M
VE
18
19
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