How to keep your fuel store in top condition

Take care of your fuel store and get the best out of your biomass boiler!

Looking after your fuel store will in turn keep your biomass boiler in good working order. Regular store cleaning will help ensure the smooth and efficient running of your biomass installation. It will also save costs on potential boiler breakdown issues. This will pay dividends in making your biomass heating system as efficient as possible – even maximising your RHI payments.

Pellet quality

In November 2022 the quality criteria of wood pellet used by recipients of the Renewable Heat Incentive (RHI) was suspended for 12 months. This means that wood pellet does not currently need to meet ENplus A1 standards. Lower quality pellet poses a greater risk to the running of your biomass boiler which makes it even more important to get your fuel store cleaned regularly.

But even the highest quality wood fuel will still contain a small amount of fines. Whilst fines and residues may seem innocuous, a build-up in your fuel store can create blockages and other problems such as combustion issues. That’s why ENplus  recommend that you organise a fuel store clean after every five deliveries or once every two years (whichever comes sooner).

Please bear in mind that wood pellets lose their ENplus accreditation once they are removed from a store. So it’s always best and more cost effective to let your store run as low as possible before a clean.

When it comes to getting a fuel store clean there are a few different services you can choose from:

Planned Cleaning:

The technician removes all fines and dust from the hopper during a planned cleaning service. Cleaning only applies to amounts of up to 250kg, anything above this is considered an extraction.

We don’t recommend that individuals clean out their own fuel stores due to health and safety risks. Harmful carbon monoxide emissions can build up in hoppers and oxygen levels can be depleted. Cleaning really is best left in the hands of the professionals who will follow the correct safety procedures and have the right equipment for the job.

What happens during the cleaning process?

This involves using an industrial vacuum to remove accumulated fines on the bottom of the fuel store and on walls, auger tray and other areas. AMP Clean Energy, along with other wood fuel suppliers, provide this cleaning service with in-house confined-spaces trained personnel.

How long does a clean take and how do I prepare for this?

There are many factors to take into consideration when cleaning a fuel store.  This includes the volume of residue in the store, what condition the pellets are in, and any access issues the technician may face.

To prepare for your fuel store clean, open the store for ventilation at least 15 minutes before the technician’s arrival. You should also switch the boiler off and ensure there is a suitable, level and safe working environment.

Unplanned extraction:

This tends to take place when maintenance workers need to access the hopper. During an extraction up to 14 tonnes of pellets can be removed from a fuel store.

 How long does an unplanned extraction take and what do I need to do to prepare?

There are a number of issues to take into account during an unplanned extraction. These include how many tonnes of pellet are left in the store, the condition of the pellets and whether the technician encounters any access problems. As a guide it takes approximately three hours to extract four tonnes of pellets.

You will need to open the fuel store for ventilation at least 15 minutes before the technician’s arrival. You should also switch the boiler off and ensure there is a suitable, level and safe working environment.

Cleaning and Extraction

You can organise for both these services to be done professionally at the same time. First, the pellets will be extracted and then the store will be cleaned of residues and fines. Some suppliers can organise re-delivery of wood fuel on the same day, saving you time and money. Alternatively you can schedule re-delivery for a later date to allow maintenance workers access to the store.

Caring for your biomass boiler

Once your fuel store is clean and refuelled it is worth booking a biomass boiler service ahead of the winter heating season. Many customers, including those at AMP, will already be on service and maintenance contracts. This means that regular maintenance by expert biomass engineers is guaranteed. However, if you are not on a contract, it is worth checking if your boiler is due a service.

Full guidelines on the operation of fuel stores from the UK Pellet Council, ENplus and the European Pellet Council can be found here.