19
Direct emission into the atmosphere
Natural draught boilers can discharge flue gas directly into the atmosphere via a duct which goes through the outside walls of the buil-
ding and ends with an anti-wind gust device terminal.
The flue gas exhaust duct is to comply with the following requirements:
- its sub-horizontal part inside the building must be as short as possible (not longer than 1,000 mm);
- it is not to have more than 2 direction changes;
- it can host only one single boiler flue gas exhaust system;
- its section, which is passing through the wall is to be protected by a sheath duct; the part of the sheath duct facing the inside of the
building is to be sealed, while the part facing outwards is to be left open;
- its end section, on which the terminal is to installed, is to protrude from the wall of the building for a length of a
least twice the diameter of the duct;
- the terminal is to be positioned no less than 1.5 meters higher than the flue gas exhaust duct from the boiler (see pic. 8).
2 Ø min.
2 Ø min.
1,5 m min.
1,5 m min.
Ø
Ø
2 Ø
2 Ø
1 m max.
1 m max.
Pendenza
min. 3 %
Pendenza
min. 3 %
> 3 Ø
>
3 Ø
0
1
3
6
5
4
2
bar
1
3
5
4
2
bar
0
1
3
6
5
4
2
bar
1
3
5
4
2
bar
Pic. 8 – Connection to the chimney for CTN model
400
700
250
Ø 130,8
121
200
200
0
1
3
6
5
4
2
bar
1
3
5
4
2
bar
Pic. 9 – Dimensions for connection of CTN model to the chimney
Slope
Slope
