Not all pellets are the same: it is essential to pay attention to quality!
The spread of pellets over the years has led to an increasing supply, sometimes of dubious quality.
To know how to make the best choice, it is essential to know the characteristics of quality pellets, aware of the risks involved in using poor pellets.
What are the main characteristics of pellets?
- Calorific value: should be between 4.5 and 5.5 kWh/kg. The higher the number, the better the quality of the pellet
- value for ash residue: indicates the degree of dirt that the pellets leave inside the machine, the value should be less than 1%
- Moisture percentage: must not exceed 8%. If higher, it decreases the calorific value of the pellet, causing a waste of fuel
- dimensions: they are important to optimize combustion and avoid operating failures. Within the tolerance limits set by ENplus certification, their diameter must be 6mm, their length must not exceed 40mm
What are the certifications of pellets?
TheOrdinance against Air Pollution (OIAt) requires that only natural lubricants be used for pellet production.
It is expected that in the future the OIAt will require that only pellets certified to the ISO standard can be sold in Switzerland. In Switzerland, the reference standard is the SN EN ISO 17225-2. The pellet that meets the standard dictated by this standard is ENplus certified.
This certification divides pellets into 3 categories:
- A1: the best quality
- A2: second choice
- B: third choice
Using pellets that are not certified or have certifications lower than ENplus A1 causes most stove and boiler manufacturers' warranties to lapse.
The ENplus mark, not only indicates that the pellets fulfill the requirements dictated by ISO 17225-2, but goes further, certifying the entire supply chain, from production to storage to transportation to your homes. Thanks to a unique certificate number, you can trace the origin of the pellets you purchase.
What problems can uncertified pellets cause?
The minor damage that can happen is that the stove or boiler gets dirty more quickly, with the need to clean it more frequently.
In the case of low-calorific pellets, such as those made from birch, on the other hand, the machine does not reach the yields stated by the manufacturer, so it burns as much but does not heat as it should.
On the other hand, the opposite can happen with pellets that are too calorific, such as those made of oak, whose combustion can even go so far as to deform internal parts of the combustion chamber, resulting in the need for replacement. Such replacement is not covered by warranty, as the latter lapses if quality pellets are not used.