9
2.
For the Installer
Diagram 1 water-side resistance
Pressure loss (mbar)
Flow
rate
(m
3
/h)
LWK 180 – 300
2.2.10 Combustion air
The combustion air is drawn directly by the device from the installation room, therefore the installation room has to
be adequately ventilated. The combustion air should be directed to the vicinity of the boiler and must be free from
pollutants (gases, vapours and dusts), otherwise malfunctions and increased wear (e.g. corrosion) may occur.
Attention!
The configuration of the entire system must comply with the requirements of regional legislation,
applicable regulations, standards and guidelines.
Applicable for Austria (excerpt from ÖNORM H 5170):
The area of the free minimum cross-section must be 5 cm
2
per kW of the boiler‘s nominal total output
1
.
The opening to the outdoors for combustion air should be designed as follows:
– the flow of air must not be restricted in any way by the weather (e.g. snow, leaves),
– the free cross-section area remains the same when taking the cover grille, discs etc. into consideration.
Applicable for Germany (excerpt from the Firing Ordinance, September 2007):
For hearths with a nominal output of not more than 50 kW in total that are dependent on surrounding air, supply
of combustion air will be sufficient providing that every installation rooms has an opening that vents to the atmos-
phere with an unobstructed cross-section of at least 150 cm² or two openings of 75 cm² each, or pipes leading
outside with a technically equivalent cross-section.
Information!
Malfunctions or complaints occasioned by inadequate combustion air will not be covered by the
guarant
ee!
1
The boiler‘s nominal total output is the sum of the nominal outputs of all heat generators installed in the same boiler / installation room.
2.2.9 Water-side resistance (pressure loss)