Whilst maintenance is minimal you will need to clean and remove the ash from your biomass boiler. The frequency that you remove ash is dependent on the burn rate which will differ in summer and winter but as guide will be once per month. Ash quantities are very low usually less than 1% of the fuel burnt.
Mid to top range biomass boilers have built-in self-cleaning mechanisms. A self-cleaning system will collect ash from the combustion grate and the heat exchanger tubes.
If there is no automatic ash cleaning mechanism you will need to shut down the boiler periodically and this will need to be done by hand. If the ash is not cleaned out regularly, it will build up and adversely affect combustion conditions, which can lead to boiler failure and shut down.
Some boilers also have a mechanism for compressing the ash which reduces the number of times the ash bin needs to be emptied.
Annual Boiler Servicing Maintenance
Your boiler will also require an obligatory annual maintenance / service check which will cost around £100.
All wood burning stoves and biomass or wood boilers need the chimney and flue pipe regularly swept to remove soot deposits and prevent blockage.
HETAS recommend that this “should be done at least twice a year, preferably before the heating season.