Wood fuelled boilers should be kept clean and swept regularly to remove ash. Ash quantities are generally very low (under 1% of fuel volume), but you will still need to empty the ash bin of the wood boiler. This is likely to be weekly and never more than once a day. Most appliances now particularly boilers have self-cleaning systems built in. A self-cleaning system will collect ash from the combustion grate and the heat exchanger tubes. If there is no automatic ash cleaning mechanism in place the boiler will need to be shut down periodically so that this can 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.
If you have a wood burning stove or boiler the chimney and flue pipe must be swept regularly to remove all soot deposits and prevent blockage. HETAS recommend that this “should be done at least twice a year, preferably before the heating season to check that the flue has not been blocked by bird's nests for example and also at the end of the heating season to prevent soot deposits from resting in the chimney during the dormant period”.
Types of Fuel
- Wood chips are not suitable for heating a single house but can be used to heat larger buildings or groups of houses.
- Pellets are much easier to use and much more controllable than logs.
- Pellet boilers can run automatically in much the same way that gas or oil boilers operate.