No, biomass pellet boilers only burn wood pellets. However, the ETA SH-P with Twin has the option to burn log wood or wood pellets and the ETA Hack can have a gas recirculation kit fitted allowing it to burn wood pellets.as well as wood chips.

Yes, just like oil and gas boilers biomass boilers need an annual service. Biomass boilers should be serviced at least once annually to ensure efficient operation. Each boiler has a certain fuel throughput before a service is required, so more frequent servicing will be required if it is used excessively. Your boiler needs to be properly maintained as instructed by the manufacturer, so as not to void your warranty and for RHI obligations, Ofgem may stop payments otherwise.

The running costs of biomass boilers are dependent on the fuel used and how you obtain your fuel. Bagged wood pellets is the least cost effective, having bulk delivered wood pellets is much more economical. Wood chips are a cheaper option than wood pellets, but the calorific value per tonne is less than wood pellets and it’s very dependent on the moisture content (<20% is best). If you can chip your own wood then running costs are reduced even further. Likewise, with log boilers if you have access to your own wood then running costs are minimal. Also, with the RHI payments for renewable energy, overall costs are much lower than using fossil fuels.