In our fuel tips section, you will find lots of useful information about your ESSE wood burning stove or range cooker, from types of wood to tips on how to light a fire.
It is essential to burn wood that has been properly ‘seasoned’, in other words, it has been left to completely dry out for between ten and twenty four months, depending on the type of wood. Never use chemically treated wood or artificially created products such as particle board.
Ideally you should plan fuel requirements for your ESSE wood burning stove or range cooker a season ahead, and store your logs in a dry location where air can circulate through them.
Just click on the headings below for some helpful tips and more information about the types of wood suitable for wood burning stoves and range cookers, how to store and season wood, how to light a fire, what happens in the wood burning process and some of the environmental benefits of using ESSE wood burning stoves and range cookers.
If wood is burnt cleanly then smoke, which contains some pollutants and particulate matter is reduced. ESSE’s unique, patent pending Afterburn2™ system significantly reduces smoke and produces an exceptionally clean burn.
So when you use a Woodfired ESSE stove you are making a valuable contribution to the future health of our planet. It is also worth pointing out that the wood ash is an excellent plant fertiliser and can be put to good use in your garden or vegetable patch.
It makes sense to extend those carbon neutral, environmental and cost benefits to the provision of domestic hot water and also to powering your central heating system.
It is a cheap way to heat too. In addition to the relatively low cost of wood as a fuel, all Woodfired central heating products are subject to only 5% VAT as part of a government initiative to encourage carbon neutral heating products.
Burning wood responsibly
Some stove owners are lucky enough to forage for their fire wood but many will need to buy their fuel from a supplier. We strongly recommend that you only buy wood from FSC (Forestry Stewardship Council) member suppliers, like Certainly Wood who obtain all of their wood from properly managed forests.
Types of Wood
The difference between ‘hard’ and ‘soft’ woods is the density of their cells or fibres. The harder a wood, the greater the density and quantity of fibres in any square inch of that wood.
As a general rule, deciduous trees (those that lose their leaves in the autumn) are usually thought of as hardwoods and evergreen trees (such as pines, firs and larches) as the softwoods. As with all general rules, there are exceptions so it is worth taking the time to understand the nature of the wood you intend to burn.
Assuming that the wood is reasonably dry, the weight of a cubic metre of good hardwood may be up to 50% more than that of a cubic metre of softwood. This means that the same volume of hardwood will provide you with more fuel to burn than an equal amount of softwood, simply because it is more dense and therefore contains more substance.
The other advantage of good hard firewoods is that the stove does not need to be fed as often, and the charcoal-beds made by the glowing wood may burn more easily overnight.
Oak – Very dense so difficult to dry. Burns very slowly and gives off lots of heat.
Beech – Produces good flame and heat. Has a tendency to spark.
Hard woods tend to take longer than softwoods to fully dry out. Oak, for example, is very slow to dry out and ideally left for two years.
Because softwoods like pine and larch contain a lot of resins and pitch, a popular misconception is that they will fur up the chimney with creosote more easily than a hardwood like oak. This is not necessarily true at all. It is not the pitch that is the problem, it’s the water IN the pitch. Once the water in the wood has evaporated, that pitch becomes high octane fuel!
When dry, softwoods burn much faster than hardwoods and have a tendency to spit and crackle. Softwood can be used as firewood and indeed mixed with hardwood but is generally not regarded as the best type of wood for maintaining a fire over longer periods.
Softwoods cut in the previous winter should, with proper storage, be ready to burn the next autumn.
How Wood Burns
The presence of all that moisture tends to keep ‘putting out’ the fire, therefore making it burn very poorly, which tends to produce a lot of creosote and pollution. Properly stored and seasoned wood will help to minimise these problems.
As the heat of the fire intensifies, waste-gases (smoke) are released from the wood. Unburned smoke is emitted into the air either as pollution, or condensed in the chimney causing creosote build-up. It takes time for the air in your chimney to heat up. When it is still cold you get an effect similar to the condensation of hot breath on a colder window or mirror. So when the by-products of combustion (smoke in the form of gases) exit the stove, and flow up into the relatively cooler chimney, condensation occurs.
If the wood you are using is water logged, or green, the fire will tend to smoulder and not warm the chimney sufficiently. Wet wood causes the whole system to be cool, and inefficient. In contrast: dry wood means a hot fire, which results in a hot flue, and a hot flue means much less creosote clogging up your chimney.
When most of the tar and gases have burned, the remaining substance is charcoal (ash in it’s finer form). A hot bed of charcoals and ash can enhance the combustion process when burning larger pieces of wood. Start with a small fire to develop a bed of glowing embers. As the charcoal bed develops and the cooker heats up, slowly add larger and larger pieces of wood. It takes time to build a good charcoal bed, but it is well worth the effort. Only empty excess ash periodically and always leave a bed of ash on which to light the next fire.
How To Light a Fire
Storing and Seasoning
Green wood will generally burn poorly and inefficiently, because it can have from 50% water (for example: Ash) to as much as 140% water (for example: Elm) in its cells. It may be hard to light, smoulder, not put out any heat and cause more than the usual amount of creosote to build up in your chimney.
So your aim should be to dry the wood out to below 25% moisture content, this process is called seasoning. As the name implies, you should store your wood for a season or so, while it dries, but there are things you can do to speed up seasoning by cutting the wood now rather than just before you use it.
Wood is composed of bundles of microscopic tubes that were used to transport water from the roots of the tree to the leaves. These tubes will stay full of water for years even after a tree is dead. This is why it is so important to have your firewood cut to length for 6 months or more before you burn it, it gives this water a chance to evaporate since the tube ends are finally open and the water only has to migrate a foot or two to escape. Splitting the wood helps too by exposing more surface area to the sun and wind, but cutting the wood to shorter lengths is of primary importance.
Here’s how you can tell whether your wood is ready or not: Well seasoned firewood generally has darkened ends with cracks or splits visible, it is relatively lightweight, and makes a clear ‘clunk’ when two pieces are beat together. Green wood on the other hand is very heavy, the ends look fresher, and it tends to make a dull ‘thud’ when struck.
When you build up a store of firewood, remember that the wood may start to deteriorate after 4 to 5 years, although this is of course variable and depending on storage conditions and species involved.
Pre seasoned and kiln dried wood
Wood can be bought pre seasoned but check its authenticity before buying. High quality kiln dried hard wood and kindling is also available from Certainly Wood who are the leading specialists in the supply of fire wood. All their wood is guaranteed for immediate use and will deliver excellent performance.