Wood burning stoves, as the name suggests, you can only burn wood logs.
Wood burns better on a flat bed of ash and draws air in from above to help it combust therefore a wood burning stove has no grate. There is a flat surface for the wood to sit on. Wood burning stoves can give out a less consistent heat and aren’t recommended for overnight burn, but they create the prettier flames, A 316 Stainless Steel Grade Liner is suitable for Wood Burning only.
If you only plan on burning smokeless coal on the odd occasion having a multi-fuel grate permanently in place will reduce the efficiency on the wood that you will be burning the majority of the time.
Multi-fuel stoves can burn a variety of different fuels
Multi-fuel stoves can burn a variety of different fuels such as smokeless coal, peat or turf briquettes, anthracite, and wood logs.
Although you can only use Smokeless fuels, you still have more options than with the woodburner, therefore this makes the multi-fuel stove more versatile.
Multi-fuel stoves need a raised grate at the bottom that lets the air circulate underneath the fuel, and allows you to burn coal and other fuel types. Smokeless fuels require lots of air underneath to get and keep them alight. Ash from multi-fuel stoves falls through the riddling grate and into an ashpan below, and you must empty it often to prevent the ash building up and stopping air flow. Manufacturers recommend a 904 Grade Stainless Steel Liner for burning Smokeless fuels.
So, there are the choices, if you’re mostly going to be burning wood then using a multi-fuel stove is much less efficient because the wood won't burn as well on a grate, but you do have a lot more choice when it comes to fuel. If you do have a multi-fuel stove and feel you are mainly burning wood an idea, is you can allow the ash to build up on the grate, creating a bed for the wood to burn on.
A multifuel Stove means you can burn difference fuels separately; it is never recommended burning wood and smokeless coal together. it is inadvisable for the following reasons:
Smokeless coal likes air underneath and wood likes air from above. One or both fuels will be burning inefficiently. The water left in the wood can mix with the sulphur in the smokeless coal creating a caustic chemical that can rot internal parts and cause premature liner failure. Flue Liner Manufactures will test for this and it could void your Liner warranty.
