Types of Stove        

 
Aside from aesthetics, when selecting your stove it is also important to consider Fuel type, intended use and efficiency rating (highly efficient cleaner burning stoves are more likely to be approved for use in smoke control areas - see smoke control areas).
 
Fuel type - There are three main categories of stove, wood burning, pellet burning and multi fuel.
 

Exempt Appliances        


Exempt appliances are appliances (ovens, wood burners and stoves) which have been exempted by Statutory Instruments (Orders) under the Clean Air Act 1993 or Clean Air (Northern Ireland) Order 1981. These have passed tests to confirm that they are capable of burning an unauthorised or inherently smoky solid fuel without emitting smoke. see http://smokecontrol.defra.gov.uk/appliances.php.

An exempt appliance is inherently cleaner burning and therefore more efficient than a non-exempt appliance.

Advice: for safety reasons, care should be taken to ensure that all exempt appliances are correctly installed and properly maintained (including flues and chimneys). Only fuel for which the appliance is designed should be used.

For further details of smoke control Areas, authorised fuels and exempted appliances please visit http://smokecontrol.defra.gov.uk/ or http://www.windsorandetonstoves.co.uk/smoke-control-15-w.asp

Wood Burning Stove    

 
Wood is a hugely important renewable fuel and when taken from managed sources it is the most environmentally friendly fuel available. When burning, wood releases exactly the same amount of carbon dioxide as it has accumulated when growing so is practically CO2 neutral.
 
Correctly seasoned wood can also be a very efficient and economical fuel choice. Freshly cut wood typically contains around 60% water (the amount of water content will vary depending upon the type of wood and the time of year the wood is harvested). When burning freshly cut unseasoned wood much of the energy stored in the wood is used to burn off this water; this results in a lower energy output per kg, lower heat output and a greater deposit of tars throughout the flue system. Seasoned wood burns far hotter and far cleaner than unseasoned wood. Energy output from seasoned wood (typically 20% water content) is on average 50% greater than that of unseasoned wood.
Energy output per type of correctly seasoned wood will vary with hardwoods typically providing 4kWh/kg and softwoods providing around 2.6kWh/kg per.
 
Windsor and Eton Stoves supply a range of log stores and accessories which provide everything you will need to correctly store and season your fuel supply. Link Accessories
 
Wood burning stoves are designed to burn wood only. When burning, wood takes its oxygen supply from above and not from below therefore a wood burning stove will have a flat internal base and will not typically have an internal grate.

Pellet Burning Stove     


Pellet burning stoves are both environmentally friendly and highly economical to run; offering all the simplicity and convenience of a modern appliance with the beauty and warmth of a contemporary wood stove.
 
Pellets come pre-seasoned offering the highest possible energy output of a wood based fuel (typically 5kWh/kg). As pellets create such a high energy output there is very little waste whatsoever (on average 2% ash) requiring only very occasional cleaning.
 
Appliances are self lighting and electronically controlled, carrying a built-in pellet store will run for many days between re-fuelling. This makes pellet stoves an ideal choice for modern living.
 
 

Multi fuel Stoves            

 
The versatility of Multi fuel stoves makes them a great choice. Designed to burn both smokeless fuels and wood. Multi fuel stoves offer flexibility and convenience of fuel choice.
 
Smokeless fuels e.g. smokeless coal and anthracites offer a very high energy output per kilo (e.g. Anthracites 9.42kWh per kg) and will typically burn for far greater periods than wood meaning less refills.
 
Smokeless coals require air from below to burn efficiently, therefore a multi fuel stove will feature an integral grate.

Radiant or Convector? 

There are two principal stove types radiant and Convector.
A convector stove rapidly distributes warmth into the surrounding room. A radiant stove concentrates heat around the stove.The type you choose will therefore greatly depend on what you want your stove to do. If you want cosiness and warmth close to the stove, the radiant stove is a great choice. If, on the other hand, the stove is also to play an effective role in heating your home as a primary heat source, you should consider a convection stove.
 

Stove Materials         

 
When selecting a stove choice of materials is an important consideration.
 
Steel stoves will warm rapidly but do not hold heat well, cooling relatively quickly. A steel stove offers convenience of rapid heat and is typically specified as a secondary heat source.
 
Cast iron stoves are inherently efficient. A cast iron stove will take time to warm but then hold heat very well indeed and radiate heat evenly. They are extremely well suited to long burn cycles and use as primary heat source.
 
Soap stone heat store. Soap stone is a fantastic extremely effective natural heat store and often features in the design of modern appliances. During a burn cycle heat is accumulated in the integral soap stone heat store. Depending upon the size of heat store offering 8 to 24 hours of continuous heat output following a burn cycle. Therefore most suited to continuous heating needs.

Minimum Efficiency.             

 
The efficiency of a stove tells you how much of the energy in a fuel will be given to the room when you use the stove. The below are the minimum legal efficiencies for new appliance and stove installations.
 
ROOM HEATERS/STOVES

Room heater without boiler – 65%
Room heater with boiler – 67%
Note. The standard test fuel for Room heaters is an anthracite based briquette and/or
wood logs.
Pellet Fired Stoves without boiler – 70% (at nominal load), 65% (at part load).
Pellet Fired Stove with boiler – 75% (at nominal load), 70% (at part load)
 
Most imported appliances quote net efficiency / output. For appliances that do quote net efficiencies the following factors will to help to round up to gross gross efficiency of an appliance. Note: this will give approximate values.
 
Conversion factor for wood: Net x 0.91 = Gross
Conversion factor for wood pellets: Net x 0.926 = Gross
Conversion factor for anthracite or  manufactured smokeless fuel: Net x 0.98 = Gross
Conversion factor for bituminous coal (house coal): Net x 0.97 = Gross

Direct Air (Closed Combustion) Stoves  

A stove requires air in order to burn safely and efficiently so any lack of adequate ventilation will inhibit combustion and can be extremely dangerous.
 
For example an extractor fan located in the same room as a stove will compete for available air and so should be avoided where possible.
 
Ventilation requirements for stoves are based upon building permeability rates and the Kw output of the stove. These are covered in Building Regulations Document J, Part 1. A registered HETAS Installer will be able to advise on your specific ventilation needs.
 
If ventilation is required then this can be achieved either through addition of a passive external air vent or a direct air supply to the stove.
 
A passive vent using an internal baffle will minimise external noise ingress and draught through the vent. When a stove is lit it will pull air from the vent towards the stove, therefore where possible locate a passive vent close to the stove and avoid locating across a room.
 
There are a large number of appliances that offer a direct outside air connection. A stove with a direct air supply ensures that the integrity of your home’s insulation can be maintained so is a better all-round option and a great solution in this case. There are two direct air types, fully room sealed and partially room sealed, with the partial taking some air from the room and so potentially requiring additional ventilation.

 

For friendly, professional advice call Windsor & Eton Stoves today on 0800 678 5041 or email sales@windsorandetonstoves.co.uk