Baxi Bioflo Installation & Servicing Instructions Manual page 12

For the Installer
Air intake from ventilation draught in the chimney; flue in the chimney:
The combustion air is drawn in through an unobstructed ventilation draught in the chimney – Figs. 3, 4. The
openings for the intake air and the flue gas are only allowed to be located with a square with a 500 mm side
length. This ensures that the same air pressure always prevails in the openings (even in very windy conditions).
Only flue gas systems that have been tested and approved for solid fuel applications, such as the Schiedl
Absolut with thermal ventilation, the Plewa air flue gas system Univers KE or the Universal pipe flue with
thermal vent may be used.
Opening
The opening should be designed such that a dangerous volume of flue gases is not sucked away into the vent
and wind-related pressure fluctuations impact as evenly as possible on the vent and flue gas shaft.
If using barred air inlet openings, the opening's free cross-section should be increased by at least 20 % com-
pared with air intake cross-sections defined in detail X. The mesh width of the barred openings should not be
any less than 10 mm.
Conditions:
≥ 2 D
H
Ü h
≥ 5/8 D ≥ 10 cm
h and h
A h A
0 cm ≤ e ≤ 8 cm
Fig. 3 Cross-section of ventila-
tion draught and flue
Legend
H ........Distance from opening of flow-out plate
Ü
h ........Distance of flow-out plate from head of supply air shaft
A
and/or flue gas shaft
e ..........Distance of flow-out plate from exterior walls
D ........Inner diameter of internal pipe
h
5
6
Fig. 4 Flue in the chimney,
air supply in a free ventilation draught
1 ..........FireWIN
2 ..........Combustion air line
3 ..........Connecting piece
4 ..........Air/flue gas system
5 ..........Flue
6 ..........Air line
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