© KWB – Kraft und Wärme aus Biomasse GmbH
IM Easyfire 10/2008
Page
69
6 Measuring the boiler
6 Measuring the boiler
6.6
Boiler analysis: Flame aspect
• Orange: with wine-red tips that transition to black threads: Lack of oxygen
• Inside blue to dark red: Combustion temperature (to) low
• Glistening white: Combustion temperature (too) high
• Sparking: A lot of sparks means a lot of fly ash
6.7
Boiler analysis: Odour
• “Smokehouse odour”: Stings the eyes when opening the combustion chamber door: High hydrocarbon content
and CO values, wet, resinous fuel.
• “Coal-burning stove odour”: Lack of oxygen, high CO values, soot
6.8
Boiler analysis: Ash
• Cement-like, heavy, snow-white to dark grey, does not get black: Wood ash, colour depends on the ash
composition and on the combustion temperature: In order.
• Extremely fine, light, mealy: Paper ash! Should not occur.
• Coarse, angular: Soil, sand, glass, cement content in the fuel! Should not occur.
• Coarse, rounded, melted: Metal, grain content sinters the ash together, ash melts due to high temperatures
(extremely rare)! Should not occur.
• Charcoal pieces, fine: Fine fuel particles are blown off of the plate! Should not occur, measurements are
required.
• Charcoal pieces, coarse: Coarse fuel particles are overthrust! Should not occur, measurements are required.
• Ash quantity: A lot of ash (more than 2 % of the fuel quantity) always means impurities and unusual ash behaviour.
(For example bark has up to 10 % ash (10 x the quantity) relative to standard pellets)! Should not occur.
6.9
Boiler analysis: Coatings in the combustion chamber
• Glossy soot (glossy black, hard): Poor combustion or no after combustion (puff-back); the unburned flue gases
condense on the boiler wall.
• Black shreds hanging from the combustion chamber ceiling: Boiler leak; glossy soot occurs when the boiler
is at a standstill and burned off at full load. Danger of chimney fire!
• Soot (dull black, mealy, stringy, beard formation): Lack of air or combustion is too cold; carbon precipitates
when the flue gas cools.
• Light to white, mealy: High combustion temperature; volatile ash content condenses on the boiler wall.
• Light to white, beard formation: With proportion of volatile ash; grain, grass impurities.
Maintenance instruction:
The flue gas channels must be cleaned regularly in accordance with the chimney sweep
ordinance!
MA-Easyfire 10.2008_EN.indd 69
MA-Easyfire 10.2008_EN.indd 69
30.03.2009 13:30:10 Uhr
30.03.2009 13:30:10 Uhr
