Click on the questions below for answers.

What is HETAS?

HETAS (Heating Equipment Testing and Approvals Scheme) is the only specialist organisation approving biomass and solid fuel heating appliances, fuels and services. This also includes the registration of competent installers and servicing businesses.

What protection or support does HETAS offer after installation?

HETAS strives to promote and monitor continuous improvement in the safe installation and use of solid fuel appliances, systems, chimneys & flues and in their maintenance. As such, we are keen to be advised of any non-compliant installation carried out whether by a non-registered HETAS or registered HETAS engineer.

Please feel free to call or email us at any time for additional support or advice, before or after your HETAS installation takes place. Contact us

3 Steps to check that your installer is HETAS registered

HETAS Registered Installer Logo

I have an existing wooden beam on my fireplace, is this okay?

Mostly yes. Each appliance and chimney manufacturer specifies the safe distances from the beam in relation to the installation. Some manufacturers can supply additional heat shields to reduce distances in challenging installations.

A survey of the proposed installation will give further clarity on whether the beam position is OK or whether shielding or non-combustible alternatives can be specifically designed to look like the real thing. It would be good practise to seek an appraisal from your local HETAS registered installer:

Click here to find your local HETAS installer

Can I install my stove myself and then get it approved?

It is never OK to install a stove and not tell anyone. It is a legal requirement that either a registrant of a Competent Person self-certification scheme is used (and notifies the work via their scheme to the Local Authority); or a Building Notice is applied for from your Local Authority Building Control Dep’t prior to installation (there is a Building Control fee for their service). We strongly recommend the installation is carried out be a HETAS registered installer to ensure the installation is safe and complies with relevant Building Regulations and Standards. The certificate of compliance will be needed if or when you move home.

Find an Approved HETAS installer www.hetas.co.uk/find-installer/

What size does my stove need to be?

Your stove output is calculated dependant on the space to be heated. This along with other factors will indicate the size of the appliance required. Correct sizing leads to greater efficiency and more effective heating. We would always encourage this to be calculated and advised upon by a registered installer.

It would be good practise to seek an appraisal from your local HETAS registered installer, who will be able to carry out all the required calculations for you as your technical competent engineer.

Click here to find your local HETAS installer

Can any property have a stove?

Within reason any property may be suitable irrespective of whether a chimney is present. In most properties without an existing chimney a system chimney may be installed as opposed to building a new masonry chimney and may run within the property or externally providing it is safe to do so. It would be good practise to seek an appraisal from your local HETAS registered installer.

Click here to find your local HETAS installer

I’m buying a property with a stove, what do I need to do?

Any solid fuel appliance fitted since April 2005 will require a document called Certificate of Compliance. Check if the chimney has been swept and the appliance services. If not, have both of these things done.

Click the following link to read more: https://www.hetas.co.uk/consumer/certificate-of-compliance/

The certificate of compliance is normally provided by your solicitor, from the previous homeowner, during the purchasing/conveyancing process. If you have not received this document, please contact your solicitor or Contact us for future support.

What fuel can I use with my new stove?

Make sure you select a fuel type that matches your appliance’s operating instructions and warranty for a long, reliable and safe service.

If you live in a smoke control area, use a fuel allowed by Defra and/or the appliance manufacturer. Authorised fuels are listed on the Defra website

It is vital for you to determine whether you have (or want) a wood burning stove or a multi fuel stove. Wood burners have flat beds on which to lay wood log fuel, while multi fuel stoves have grates. You can put wood on a multi fuel stove, but you can’t effectively burn coal on a wood burning stove.

It is preferable to burn hardwoods such as beech and ash, instead of softwoods like pine or fir. This is because hardwoods take longer to burn so you will use less fuel. You can buy ready dried or seasoned wood logs to reduce the moisture content of freshly cut wood by drying it yourself, which is also called seasoning. To do this, it is best to store your wood in a dry ventilated place for at least 12 months. Wet logs will tend to blacken the glass on your stove. Burning wet wood is also very inefficient as the fire has to boil off the water in the wood before any heat is provided into your room.

To find out how dry your fuel is, and whether it is ready to use, you can buy a moisture meter. Basic moisture meters giving a good estimate of moisture content costs around £20. We do sell them at our call centre so Contact us for more information.

Click here to search for your local supplier.

How easy would it be to change the type of appliance – for example from gas to wood burner?

Any alterations to a fireplace which renders it capable of being used for a different fuel e.g. from gas to solid fuel, is subject to Building Regulations
For more information, see our Chimney and Lining advice leaflets

It would be good practise to seek an appraisal from your local HETAS registered installer:

Click here to find your local HETAS Installer

How do I find an approved wood fuel supplier?

To ensure satisfactory performance, it is important to use fuels that are of a suitable type and size. Good quality fuels are essential for safe and efficient combustion as poor quality fuels waste energy and ultimately can cost you more. All HETAS accredited fuels have undergone certification in accordance with the relevant standard, providing you with confidence that the fuels being burnt are both safe and efficient for the type of appliance they have.

Woodsure Logo

Look out for the below logos when purchasing your fuels:

Please feel free to search our website, using the following link for approved fuel suppliers: https://www.hetas.co.uk/find-fuels/

If you have any other HETAS fuel queries, please Contact us.

I have misplaced or not received my Certificate of Compliance

If the work has been carried out by a HETAS registered installer, then you can Contact Us to ask for your Certificate to be re-issued. There will be normally an administration fee £18.00 (inclusive of VAT) to re-issue your Certificate. Your certificate can be emailed or sent to you by post.

We can only post the certificate to the property address where the installation took place.
Contact us

When should I get my chimney swept?

We would encourage you to have your chimney swept at least twice a year when burning wood or bituminous housed coal and at least once a year when burning smokeless fuels. The best times to have your chimney swept are just before the start of the heating season and after your stove has not been used over a prolonged period. If sweeping twice a year, the second time should be after the peak of the main heating season.

We recommend using a HETAS Approved Chimney Sweep:

To download a free HETAS Advice Leaflet on Operating and Maintaining your stove – click here

More consumer guidance leaflets are available here:

Should a CO Alarm have been fitted when my stove was installed?

Building Regulations now makes it compulsory in England and Wales to fit a CO Alarm, whenever a new or replacement solid fuel appliance is fitted in a dwelling. The alarm must be permanently installed, be either mains or battery powered, and should incorporate self-test and audible alert if the battery or detector cell develops a fault. The alarm must be fixed in the same room where the appliance is fitted and according to its own instructions provided. Contact us.

What should I do if my CO Alarm goes off unexpectedly?

  • Turn off the appliance immediately – where it is automatically fed with fuel
  • Open the doors and windows in your home and ventilate thoroughly
  • Leave your home immediately and do not return until your appliance or boiler has extinguished and any CO has dispersed from your home completely
  • If you feel unwell, go to your doctor, call NHS Direct on 111 (0845 4647 in some areas) or if it is urgent phone 999 for an ambulance. Tell them that your symptoms may be related to carbon monoxide poisoning

Before you re use your appliance, have it inspected and the chimney checked by a HETAS Registered Installer or Approved Chimney Sweep.

Do not use your appliance until you are told it is safe to do so.

Test your Carbon Monoxide alarm!

Also referred to as ‘Test it Tuesday’ – we advise you to test your Carbon Monoxide alarm at least once a month on a day you are likely to remember. Most Carbon Monoxide alarms have a simple button for you to press in order to test that your alarm is working. For more information on Carbon Monoxide, please visit our page https://www.hetas.co.uk/consumer/carbon-monoxide/

Follow us on Twitter and/or Facebook for monthly reminders and updates. Contact us.

I am redecorating my living room; can I move my CO Alarm?

Yes but do it when the appliance is not in use.
Please fix your alarm back in the same place your HETAS Installer fixed it. This is to make sure that you are complying with Building Regulations and standards
To work safety, your carbon monoxide alarm should be located in the same room as your appliance:

  1. On the ceiling at least 300mm from any wall or, if it is located on a wall, as high up as possible (above any doors and windows) but not within 150mm of the ceiling and
  2. Between 1m and 3m horizontally from the appliance

Further details can be found in the Building Regulations Approved Document J

How to light fire safely

Wood Burning Stove
Lighting your stove in the most effective way could take a little bit of practise, but the following steps are a good guideline to follow:

  1. Fully open the primary air vent/control and air wash controls
  2. Place a firelighter or scrunched up newspaper together with some dry kindling wood on the grate. Light the firelighter or paper
  3. Leave the door slightly ajar while the fire establishes and the glass warms up. This will help avoid condensation building up.
  4. Once the fire is going, add some larger pieces of wood (Do not fill the chamber with logs)
  5. When the logs have caught flame and the fire is fully establishes, close the door completely
  6. Close the primary air control
  7. Use the air wash to control the burn rate when the appliance is at operating temperature
  8. Maintain the fire frequently with small amounts of additional fuel

The most effective technique for building the fire is to make a small stacked structure of wood by basically making a hash tag out of the stacked kindling around a fire lighter with one single log on the top, bark side down.

Mineral Fuel Stove

  • Start with a firelighter and a small amount of small sized coal
  • Set the air control to maximum
  • Once the original fuel is well alight, start to build up the fuel in the grate without overfilling the chamber
  • Reduce the air intake once the whole bed of fuel is burning well
  • Add more fuel at a frequency that keeps a good bed of red hot coals

Is it safe to purchase a new stove online?

There are many choices as with any appliance. Visit a HETAS Approved Retailer to give you confidence in getting a suitable, efficient and safe heating appliance for their home. All approved retailers contain at least one HETAS trained showroom staff member, meaning quality advice.

When purchasing a product from a HETAS Approved Retailer showroom;

  • You will have the confidence that there will be knowledgeable staff available in the showroom
  • Will purchase a safe and legal appliance with the appropriate amount of output needed to heat your home
  • Be able to identify key features of each appliance through a product labelling system to make an informed choice to suit your needs
  • Key topic advice sheets available in store for advice on maintaining your appliance efficiently and to the correct code of practice
  • They may work with local registered installers that they have a good working relationship with, making your search for an installer easier

Click here to find your local HETAS Approved Retailer

Do I live in a smoke control area?

Your Local Authority is responsible for designation and the supervision of Smoke Control Areas.

To find out if you live in a Smoke Control Area, we recommend that you contact the Environmental Health or Protection Department of your Local Authority:

Do I need to line my chimney?

The answer is often yes. Whilst there is no regulation requiring every existing chimney to be lined your installer must satisfy themselves that the chimney is free from defects and suitable for its intended use.

If any work undertaken on the chimney, including installation of a new liner, is done in conjunction with the installation of a heating appliance, then that the work is a controlled service and must be undertaken by a competent person or approved by your local area building control.

Chimneys are lined for a number of safety reasons. New chimneys may require relining to suit the fuel type being used (a gas flue liner may not be suitable for other fuels). Chimney systems that predate 1965 will often require a modern lining solution for the following reasons:

  • The flue may have lost integrity and can leak smoke into rooms or other part of the building
  • Condensates or tar can seep through chimney walls causing staining, inside or outside of the building
  • Lining with insulation included improved the operation of the appliance and flue – particularity important when the chimney is situated on an external wall
  • Defective flue systems may be eroded and rough. Thus will cause frictional resistance to the flow of the gases resulting in poor up draught
  • Large flues over 200mm, particularly ones containing voids, may affect appliance performance. Some appliance manufacturers specify smaller flues for efficient operation

Why do I need to replace or reline my chimney?

There will be one of three reasons why the existing chimney may need to be relined:

  • A chimney will need to be relined if it is found to be unsound from the results of the appropriate test by a skilled engineer
  • And/or if the cross-sectional area if the flue is too large or small for the intended appliance
  • And/or any of the existing lining is found to be unsuitable for the proposed appliance type

Find a HETAS Approved Chimney Sweep

What would be the best type of liner to use in my chimney?

Rebuilding or relining an existing chimney requires a specialist advice. We strongly advise you to discuss your options during a visit from your HETAS Installer. If you decide to re-build a masonry chimney, this is work for a builder and may require planning permission and Building Regulations approval.

However, there is a wide choice of factory made chimney relining systems that can be used. Fire-resistant precast concrete, clay and pumice flue liners or ceramic liners offer the most permanent solution, providing the existing chimney openings are big enough to take the correct size flue size to suit the proposed appliance.

Double skin flexible stainless steel flue liners offer an alternative answer if the access is difficult or the existing chimney is unable to accept other types of liners. These flexible liners can be easier to install and replace, but are not described as permanent. Significant periods of slow burning with solid fuels or infrequent chimney sweeping can give rise to corrosion damage. This can then reduce the expected life of the liner.

Insulated metal chimney systems offer a fast and convenient solution. They are robust and adaptable offering suitable solutions for many more challenging installations.

How can I check if my appliance is HETAS Approved?

The HETAS ‘Find Appliance’ search will help you to find the appliance that is right for you. Our online search facility includes approved wood stoves, open fires, cookers, biomass systems and chimney products.

To help maintain these standards, HETAS is the independent UK body recognised by Government for the testing and approval of solid fuel and biomass appliances and associated equipment and services.

Why choose a HETAS Approved appliance?

  • Have confidence that the appliance conforms to the UK building regulations in its installation and use
  • Have all relevant information on using the product in specified operating instructions for safe and effective use of the appliance
  • Freedom of choice to choose an appliance listed in the HETAS guide to solid fuel products and services to suit your individual needs on both heat output and design
  • It minimises the work installers have to undertake to check that the products meet the relevant legal and good practice requirements

How can I find out more information on the correct use of my appliance?

Always adhere to your manufacturer’s instructions. Every appliance is different and unique in its own needs and requirements to obtain the best and most efficient performance.
Here are some of our tips for you:

  • Have your stove regularly serviced and swept (see advice leaflet ‘How to look after your stove’ for more details upon this
  • Wood burns best on a bed of its own ash – you don’t have to clean it out before every use
  • Mineral Fuel – empty the pan regularly to stop ash build up and touching the underside of the grate. This will reduce the air flow around/through the grate and can lead to overheating of the grate bars and subsequent damage
  • Throat plates to be cleared at least monthly or when recommend by your manufacturer in their Instruction Manual
  • Always replace the grate and fire bricks if they become damaged
  • Check your stove door/s rope seal are air-tight. Over time, rope seals will become compressed sufficiently to allow some combustion air into the stove, reducing your ability to control the flame and also losing significant fuel efficiency.

I am concerned about the work my HETAS installer has carried out, what can I do?

We understand and value all of your concerns so in the first instance, please feel free to Contact us to share the details with us.

There is a complaint questionnaire we can send you by post or email with a set procedure in place for your protection and assistance.

Why is ventilation required and how is this calculated?

Ventilation is always required for the room in which the stove is installed, details of which will be ascertained upon survey and installed discreetly in keeping with the building fabric. This ensures that there is an adequate supply of air for combustion, to prevent overheating and for the efficient operation of any flue. There are different ways of providing combustion ventilation so advice from a registered installer can help you to get the right installation for your needs.

You should ensure that the following has been supplied by your HETAS installer prior to using your new stove: for your needs

  • Notice Plate
  • Carbon Monoxide Alarm
  • Manufacturer’s instructions
  • Either a hard copy certificate of compliance provided by the installer or one sent to you by post after the installer has notified the work electronically to the scheme

Your HETAS Safety Checklist:

  • Proper ventilation
  • Regular cleaning and sweeping
  • Always use the right fuel for your appliance – as recommended by the manufacturer
  • Keep all combustibles, including logs, at a safe distance from the hot stove
  • Do not slow/slumber burn. Do not turn the stove down for the night
  • Never leave an open fire unattended without a spark guard
  • Always use a securely fitted fireguard when children are in the house
  • Be Carbon Monoxide safe
  • Get your stove serviced annually by a HETAS Registered Installer
  • We highly recommend that you contact your insurer about your new stove as it may affect your insurance policy

…I’ve read the list of FAQs but need further support

we're here to help at HETAS

For more support please feel free to call or email us at: support@hetas.co.uk

Telephone: 01684 278170 (option 2)
Lines are open Monday to Thursday 8:30am to 5pm and Friday 8:30am to 4:30pm

Should your query relate to checking if HETAS has been notified of your installation, please provide the full address of the property where the installation was completed.

Further Reading

Please Contact us to receive a free advice leaflet(s). Our advice leaflets range from a number of topics offering you user friendly advice: