CEN/TC 295/WG 4 - Independent boilers

The application of the calculations of this document enables a verification of the emission values carbon monoxide, nitrogen dioxide, organically bound carbon as well as dust and the energy efficiency.
Complying with the calculations of this document results in emission values less or equal for carbon monoxide 1 500 mg/mn3 (1 000 mg/MJ), nitrogen dioxide 225 mg/mn3 (150 mg/MJ), organically bound carbon 120 mg/mn3 (80 mg/MJ) and dust 90 mg/mn3 (60 mg/MJ). If the calculations of this document are used in combination with suitable combustion chambers that prove lower emission values in a type test, these values are also considered to be complied with.
The user shall be aware that there might be national or local regulations, which impose stricter legal emissions and/or efficiency requirements.
This document specifies calculations for the dimensioning of Kachelgrundöfen/Putzgrundöfen (tiled/mortared stoves) based upon the required nominal heat output of the stove as declared by the producer. The Kachelgrundöfen/Putzgrundöfen (tiled/mortared stoves) are of individual one-off construction design. The document can be used for log wood fired Kachelgrundöfen/Putzgrundöfen (tiled/plastered stoves) that burn one fuel load per storage period with a maximum load between 10 kg and 40 kg (log wood with water content from 12 % to 20 %, thickness of 5 cm to 10 cm in diameter, length varies usually from 25 cm to 50 cm, and is oriented toward the combustion chamber dimensions) and a storage period (nominal heating time) between 8 h and 24 h.
This document is applicable for Kachelgrundöfen/Putzgrundöfen (tiled/mortared stoves) equipped with fireclay as interior material, with an apparent density between 1,750 kg/m3 and 2,300 kg/m3, a degree of porosity from 17 % up to 33 % by volume and a heat conductivity from 0,90 W/mK up to 1,35 W/mK (temperature range 20 °C to 400 °C).
This document is applicable for Kachelgrundöfen/Putzgrundöfen (tiled/mortared stoves) with combustion air supply from the side via a firebox door frame or the standing grate of the heating door into the combustion chamber. The document is applicable for an inflow speed of the combustion air between 2 m/s and 4 m/s.
This document also applies to the combination with combustion chambers that are suitable for one-off Kachelgrundöfen/Putzgrundöfen (tiled/mortared stoves) and for which compliance with the legally required emission values has been verified as part of a type test by an accredited and/or notified body.
The following general conditions apply to such combustion chambers:
-   with an air-fuel ratio of between 1,95 and 3,95 according to the type test;
-   with a maximum load from 5 kg to 40 kg;
-   using other suitable materials as well as fireclay.
With regard to the type test, this document is applicable for combustion chambers which are tested:
-   according to EN 15250 (or prEN 16510-2-5);
-   according to EN 13229 (or prEN 16510-2-2); or
-   according to respective national standards (e.g. ÖNORM B 8303).
This document is applicable for type tested combustion chambers designed for batch fired pellet burning if meeting the requirements according to this document (air-fuel ratio between 1,95 and 3,95, the load of the pellets shall be burned in (78 ± 20) min).
This document is not applicable for:
-   combinations with water heat exchangers for central heating or other heat absorbing elements like open water tanks etc.;
-   combustion chambers with glass plates greater than 1/5 of the combustion chamber surface;
-   mass-produced prefabricated stoves (slow heat release appliances) or partly prefabricated stoves (slow heat release appliances) according to EN 15250 (or prEN 16510-2-5).

2007-09-21  Work item deleted to 3 year time frame.

This standard specifies calculations for the dimensioning of Kachelgrundöfen/Putzgrundöfen (tiled/mortared stoves) based upon the required nominal heat output of the stove as declared by the producer. The Kachelgrundöfen/Putzgrundöfen (tiled/mortared stoves) are of individual one-off construction design. The standard can be used for log wood fired Kachelöfen (tile stoves) that burn one fuel load per storage period with a maximum load between 10 kg and 40 kg and a storage period (nominal heating time) between 8 h and 24 h.
This standard is valid for Kachelgrundöfen/Putzgrundöfen (tiled/mortared stoves) equipped with fireclay as interior material, with an apparent density between 1,750 kg/m³ and 2,200 kg/m³, a degree of porosity from 18 % up to 33 % by volume and a heat conductivity from 0,65 W/mK up to 0,90 W/mK (temperature range 20 °C to 400 °C).
This standard is valid for Kachelgrundöfen/Putzgrundöfen (tiled/mortared stoves) with sidewise combustion air supply of the combustion chamber and an inflow speed from 2 m/s to 4 m/s, whereas the height of the lowest opening is at least 5 cm above the bottom of the combustion chamber.
This standard is not valid for combinations with water heat exchangers for central heating or other heat absorbing elements like glass plates greater than 1/6 of the combustion chamber surface, open water tanks, etc. It is also not valid for combinations with heating/fireplace elements according to EN 13229. Furthermore this standard is not valid for mass-produced prefabricated or partly prefabricated slow heat release appliances according to EN 15250.
NOTE   Although for the purposes of this standard these calculations are applicable only to the requirements of this standard, the same calculations can be used for other purposes, e.g. to verify emission levels and energy efficiency in case of burning log wood or wood briquettes according to the producer’s manual.