Getting the best out of your biomass boiler

4th December 2018

Without regular care and servicing commercial biomass boilers may become less efficient, which can lead to increased boiler downtime and the possibility of lost RHI payments. Here is a summary of our expert advice to help you optimise your boiler’s performance.

Preventing ash build-up

Parts of the boiler affected by ash deposits are the combustion chamber, the heat exchanger and flue system surfaces.
Most automated biomass boilers have automatic heat exchanger cleaning mechanisms which clean some of the overall surface to assist with the efficiency of the boiler. These components gather ash over time which restricts the flow of the flue gasses, reducing boiler efficiency and output.
Many large commercial biomass boilers flue systems are fitted with cyclonic dirt scrubbers to remove fly ash and debris from the flue gases as they pass through the system. However, you must clean these scrubbers regularly to ensure efficient removal of the materials.

Beware of clinker!

Severe ash can build into clinker, which looks like pieces of crystallised ash. Clinker formation is the most significant factor in wood pellet fuel quality and can stop your boiler working.
The key factors are the melting temperature of ash residues and the percentage of ash in the fuel. Pellets with a higher ash content can be contaminated with non-wood products, which can reduce the melting temperature of the ash allowing clinkers to form on the grate, disabling the burner.
Keep an eye out for clinker. If you’re concerned about the amount of clinker in your boiler it is worth calling out expert help to assist with this.

Getting the right fuel consistency

Most wood chip biomass boilers need fuel with a consistent moisture content which can vary from 25% to 60% but most typically is around 30%.
If the moisture content of the wood chip is too high it can cause a boiler to shut down, while if it is too low and the wood chip is too dry it will burn too quickly.
The best thing you can do to ensure your wood fuel is the right consistency is to check that you are receiving a reliable supply of high-quality wood chip at the correct moisture content. It is best to buy woodchip from a supplier which is Biomass Suppliers List (BSL) authorised and Woodsure Plus accredited.

Regular boiler Servicing

Biomass boilers do require regular servicing to ensure optimal performance and minimal downtime. Boilers that burn wood chip or pellets also need regular attention when it comes to filling, cleaning and fuel delivery.

The number of times a full shut down and planned maintenance should be carried out depends on a number of factors including boiler usage levels, boiler types and boiler size. You really do need to put servicing into the hands of an expert, preferably on a regular servicing and maintenance plan.

If you opt to service your boiler on an on-the-spot basis, then these are the signs to look out for that your boiler needs servicing:
• A lot of unburnt fuel within the ash deposit chamber
• High levels of soot and clinker within the combustion chamber
• Excessive black smoke production during combustion

Flue problems

Flues are the pipes that take gases away. When they become clogged, air circulation is reduced, the boiler is inefficient, resulting in poor performance and boiler failure.
If there is no automatic ash cleaning function on your boiler then you will need to clean it and remove the ash yourself or arrange for it to be done. Please bear in mind that the boiler will need to be shut down and cooled before cleaning can take place – depending on your fuel and boiler this could be a weekly task.

High quality fuel supply

At AMP Clean Energy, our wood chip and pellet meet the highest sustainability standards. We only source our wood fuel from responsible and accredited partners and our established, robust supply chain ensures a dependable wood fuel supply throughout the winter heating season.

When it comes to wood chip our focus is on making everything – from sourcing, seasoning, to harvesting – as local as possible. All our wood chip is Biomass Suppliers List authorised and Woodsure Plus accredited.

Our low ash, low dust wood pellets meet ENplus certification, the highest quality standard in Europe, audited by the European Pellet Council.
AMP Clean Energy is also named on the Government’s official Biomass Suppliers List (BSL), which means that we can guarantee that the wood pellets we supply and the processes we follow, meet the sustainability measures set out by HETA and Ofgem, the government’s gas and electricity regulator.

Peace of mind with our Service & Maintenance Plans

Regular servicing and care will extend the lifespan of your boiler and ensure optimum performance, maximising RHI returns. There really is no substitute to putting your boiler into the hands of our team of expert biomass engineers who can help assess and advise on the service choice which is right for you. By letting AMP Clean Energy take complete care of your boiler, all operational hassle and day-to-day strain is taken away, leaving you to focus on your core business.