At Fireplace Products we love talking about stoves: not only is it our business, it’s our passion. A wood-burning stove comes with many different parts, and it is handy to understand the names and purpose of the parts so that you know what you want from your stove, and we can help you find it.
The first part of the stove you should know is the firebox. The firebox is where the fire sits. It is good to know what size fuel you plan to burn and whether the size of the fire box is capable of meeting your requirements. If you’re want to burn big lumps of wood because you’re heating a large room, you don’t want a tiny firebox.
Inside the firebox, protecting the metal sides of the stove from the intense heat and helping to make your stove more efficient, are the firebricks. Often made of fired clay or vermiculite, firebricks reflect the fire’s heat back at it to help reach and maintain a high temperature.
Extracting more heat from the gases produced by the fire that are heading for the chimney, the baffle plate usually sits at a slight angle at the back of the firebox. A baffle plate forces the gases to pass around it before they can escape up the flue. Meaning more heat is transferred to the plate and not lost up the flue.
For multi-fuel stoves, forming the base of the firebox, the grate is a cast iron base plate with gaps that allows air from below to reach the fuel, which is necessary for the fire to burn. It’s worth keeping an eye on the ash build up in the ash pan below to make sure it doesn’t reach the grate and block these gaps.
Smokeless coals require primary air from underneath the fuel bed, and a grate elevates the fuel bed off the base of the stove. A dedicated woodburner needs air from above to burn wood correctly. This is why it is possible to burn wood on a multifuel appliance although it is not as efficient as the air being injected is at a different position.
An ash pan collects the ash created by the fire in the firebox. Dropping through the grate, the ash pan can help create a bed of heat that draws in air to help the fire in the firebox.
Bringing fresh, cold air into the firebox is the primary air, often feeding through a grate’s air inlets.
Requiring balance and to add air to help the gases of a wood fire burn, a secondary air supply can be found near the top of the stove. This air is usually supplied to the firebox through a series of channels in the stove before it reaches the firebox to ensure it is heated enough to not cool the fire. For the gases of a wood fire to burn, which is above the firebed, a balanced air supply is required between the secondary and primary air vents.
There is also two types of secondary air. The first is just regular secondary air, pulled in from a vent usually at the top of the stove, and is pushed down the glass and into the fuel bed. The second is pre-heated secondary air, or pre-heated airwash, which is often taken from underneath the stove and is heated up behind the rear firebricks, brought over the top of the stove and then pushed down the front of the glass. Both types of secondary air systems have their pros and cons – check back for a future blog post on this!
Many stoves also have a tertiary air supply, drawing in air at the back of the firebox and burning unburned hydrocarbons, providing a cleaner fire with better efficiency. This is more commonly know as tertiary burn or cleanburn system.
Part of the joy of having a stove is seeing the beautiful, captivating flames dance before your eyes. However, between you and the fire is a window and this can soon become dirty from the tar build-up produced through combustion. To prevent this from ruining your view, many stoves use their secondary air control as an airwash system which sees air drawn across the ceramic heat resistant glass window. The moving layer of air slows down the rate of tarring, but it’s worth noting that tarring is not completely avoidable, but there are many products on the market to help keep clean stove glass. Providing you burn the correct fuel with a low moisture content, the glass should stay fairly clean.
In the old days, a draughty house helped keep your fire going strong, but as our houses become more energy efficient and better insulated, those draughts are no longer available, which can make it hard for your stove to get up to temperature. To combat this, some stoves come with an external air supply which brings in air from outside to fuel the fire.
Finally, we come to the chimney draw (sometimes called a draught). Not only does this remove gases and smoke from the stove, it creations suction that pulls air through the primary, secondary and tertiary air vents.
So now you know the lingo, why not put it into practice and have a chat with one of our Fireplace Products experts in-store or online and find the right stove for you today!