How to Connect a Wood Burner to Central Heating
Home heating with wood can offer UK homeowners a low-carbon alternative to an oil or gas boiler, but this is not always the case. Here we explore wood burning stoves that heat radiators, how to connect a wood burner to central heating, biomass boilers, and the key pros and cons you need to keep in mind.
What is a wood burner?
Wood burning stoves (otherwise known as wood burners or log burners) are a form of heating appliance that burns wooden materials to heat up a room. These materials can include logs, pellets and other biological matter.
Burning wood can be a low-carbon way of heating hot water, as the process only emits as much carbon as the trees absorbed while growing, making the process ‘carbon neutral’.
However, as they’re only able to heat up a single room, many homeowners are keen to find ways to better utilise the heat generated by a wood burning stove, e.g., to connect their wood burner to the central heating.
What are the benefits of wood burning stoves?
As we have already mentioned, burning wood is a carbon neutral process so they do not contribute additional carbon to the atmosphere.
Wood burning stoves are rather idyllic in their appearance and are growing in popularity as they are not only attractive additions to a room but can also be an effective and efficient heating system. Simply put, there’s no warmer feeling than from fire. Compared with radiators, a log burner will heat a room more effectively.
Wood is also a much cheaper fuel source per kilowatt hour than electricity, oil and even natural gas:
- Gas: 4.8p / kWh
- Oil: 6p / kWh
- Electricity: 13.4p / kWh
- Wood Chips: 2.9p kWh
- Wood Pellets: 4.2p / kWh
Connecting a wood burner to central heating
Wood burners will heat the space around them and provide a cosy focal point for a room, but they can also be used to provide hot water for domestic use and/or central heating.
While they probably cannot produce enough hot water to satisfy a household’s total demand, they can help to take some of the strain off the heating system and increase efficiency.
Connecting a wood burner to the central heating can be complex and will vary greatly from property to property. In the vast majority of cases it’s essential for the system to include a vent. Without a vent, pressure could build up within the system (as it would have nowhere to escape) and in the most severe cases blow the stove. This rules out being connected to a heating system which includes a combi boiler.
Never attempt to connect a wood burner to the central heating yourself – this should only be done by a professional heating engineer.
Can a wood burner provide domestic hot water?
A back boiler stove can supply domestic hot water as well as central heating. Should you not have a back boiler stove and instead a wood burner or log burner it’s still possible for a wood burner to be connected to a hot water cylinder to provide domestic hot water.
Historically, properties with a back boiler would directly connect it to their wood burner to top up the domestic hot water supply, but back boilers are outdated heating systems that are no longer being manufactured. If you have a back boiler then a heating engineer will most likely recommend that you replace it with a modern boiler.
Nowadays, to connect a wood burner to a hot water cylinder, heating engineers would use an indirect connection. Rather than heating the water directly, the wood burner heats up a coil within the cylinder. This coil in turn then heats up the domestic hot water.
To find out how much it will cost to connect a wood burner to your central heating and/or hot water cylinder, find a local heating engineer today.
Heating with a biomass boiler
Biomass boilers are essentially wood burning stoves that are built to supply central heating and domestic hot water to an entire property – a great solution for off-grid properties. The process of burning organic materials heats water via a heat exchanger which is then circulated to the central heating system or domestic hot water cylinder.
With older biomass boilers, feeding the fuel into the combustion area would have involved manual labour. However, modern biomass boilers feature a fuel storage compartment, which automatically feeds the fuel into the boiler.
So, rather than pairing a wood burning stove with a central heating system, you could turn to a biomass boiler.
Interested in a biomass boiler?
How does a biomass boiler work?
Biomass boilers burn wood logs, chips, or pellets. The heat is transferred to a hot water cylinder where it can be used in a central heating system, showers, and taps.
Biomass boilers are large heating appliances that include a combustion chamber, buffer tank, flue pipe, expansion vessel, hot water cylinder, fuel storage compartment, and an optional hopper which feeds the boiler fuel automatically.
Modern biomass boilers have fuel storage compartments which are automatically fed wood chips/pellets into the combustion area to be set alight by a probe. As the fuel burns it heats the water via a heat exchanger. While gas and oil boilers are automatically fed with gas as they are either connected to the national gas grid or a large tank of oil in the garden, a biomass boiler needs to be topped up with fuel. This can be done by hand or by an automatic mechanism called a hopper.
A biomass boiler needs to be manually emptied of ash and cleaned on a regular basis.
How much does a biomass boiler cost?
Biomass boilers typically cost between £4,000-£10,000 for a manual fed log boiler while automatically fed pellet boilers can cost between £9,000-£21,000.
Until March 2022 you can reduce the cost of installing a biomass boiler by two-thirds (up to £5,000 or £10,000 depending on your household income) by applying for a Green Homes Grant.
The best biomass boiler manufacturers include Froling, Grant, Viessmann, Warmflow and Windhager. The biomass boilers by these manufacturers include outputs up to 72 kW and can be fuelled by either wood chips, logs and pellets.
|Best Biomass Boiler Manufacturers||Viessmann||Froling||Windhager||Grant||Warmflow|
|Model||Vitoligno 300-C||T4e||LogWIN Premium Touch||Spira||Zeno|
|Output||2.4 – 48 kW||5.9 – 250 kW||13.4 – 50 kW||5 – 72kW||4 – 18 kW|
|Potential Cost||£9,000 – £10,000||£8,000 – £14,000||£7,000 – £10,000||£11,000 – £12,500||£7,000 – £14,000|
When you compare these prices to the average £1,500-£2,000 cost of a gas boiler, it can feel daunting. However, when you consider that biomass boilers are much cheaper to run and you could benefit from the government’s Renewable Heat Incentive payments, the story changes.
Note: The Domestic Renewable Heat Incentive will only be open to new applications until 2022 when the scheme will be replaced by the Clean Heat Grant. You can find out more in Clean Heat Grants to Replace the Renewable Heat Incentive.
Is burning wood for heating eco-friendly?
You are allowed to burn wood in your home, but you need to ensure that you are burning the right type of fuel in an approved boiler or wood burner.
Heating a home with a burner wood can be an environmentally friendly choice if you use approved appliances and the right types of wood fuel.
While they are growing, trees absorb carbon dioxide, a greenhouse gas, from the atmosphere. When we burn trees for heat, the same amount of carbon is released back into the atmosphere, so burning wood does not add more carbon to the atmosphere, making it a carbon neutral process.
However, burning certain types of wood can release toxic smoke, particulate matter, and man-made toxins both into the home and the outside air.
Because burning wood can be dangerous, the government has designated ‘smoke control areas’ in the UK. In smoke control areas you can’t emit smoke from a chimney unless you’re burning an authorised fuel or using ‘exempt appliances’. You can contact your local council to find out if you are in a smoke control area.
The government has also announced that the sale of bagged traditional house coal, loose house coal, and wet wood (in small units) will be phased out by 2023. Manufacturers of solid fuels will also need to show that their products have a very low sulphur content and only emit a small amount of smoke.
Get quotes for biomass boiler installation
Having a biomass boiler installed is a big investment – particularly if your home isn’t currently heated by one. So, we can help to make the process as straightforward as possible.
Our service gives you the ability to connect with as many as 3 biomass boiler installers in your area. Saving you from having to search for them yourself.
All you have to do is complete our simple online form to let us know a few details about the work involved. We’ll then use that information to connect you with installers qualified to complete the job.
Each installer will be in touch to provide a free no-obligation quote for you to then consider and compare. By comparing multiple quotes you’ll be giving yourself the greatest chance of securing the best deal possible for the installation of your new biomass boiler.
Interested in a biomass boiler?