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Why do I need a Wall Screen or a Flue Shield?
Pyroclassic Fires can be installed with a double skin half round flue shield or for minimum clearances from combustible walls a correctly sized wall screen must be installed, the clearances for these are shown in the relevant Tech Spec sheet for each fire.
Alternatively you can install a Pyroclassic Fire without wall screens if you chose to use a non-combustible wall board product such as Eterpan, Supalux or Promina board and install it as per the manufacture specifications. Usually this involves ensuring a 25mm air gap is maintained between the wall board and any timber framing, through the bottom, up between the combustible surface and the screening material and out of the top.
In some instances the wall may not contain any combustible material and therefore will not require any screening.
Pyroclassic Wall Screens now have a simple keyhole hanging system to make installation very easy.
How do I light my first fire?
1. Soak the reusable fire starters in methylated spirits. Tip: It is also handy to store the fire-lighters in a glass jar filled with meths.
2. Slide the Turboslide to the far right or far left position. This opens the air hole inside the door and allows
air to flow through acting like an old fashioned pair of bellows.
3. Place DRY kindling and a few small logs lengthways in the front of the fire chamber leaving a clear space
in front of the air inlet hole.
4. Place a soaked fire starter just under the kindling at the front of the fire chamber and light it. Try to avoid
dripping meths on to any surface when doing this as it can discolour some hearth materials.
5. Close the door.
6. Once the fire is burning really well and you have a nice bed of hot embers, move the Turboslide to the
central position (to cover the air inlet hole), this can be done slowly in several stages if preferred.
7. When opening the door to load more wood, slide the Turboslide to the far left or right open position,
and continue as in number 6.
How does burning work with the Pyroclassic IV?
Solid wood must change to gas and vapour before any burning can take place. This change occurs by heating wood to high temperatures to make the best gas fuel, low temperatures will make smoke and tars that are simply unburnt fuel. The Pyroclassic® IV is a North/South burning fire so the fire is started in the front of the fire chamber and continues along the length of the wood to the rear. To make the best use of your firewood please ensure logs are placed lengthways into the fire chamber – NOT sideways. Your objective is to achieve a high temperature in the fire chamber quickly, which is easy using the Turboslide and dry wood. You will never get the fire to burn correctly if you try starting fires with green or wet wood. The only fuel authorised for use with this appliance within Urban Clean Air Sheds and Smoke Control Zones is well seasoned wood with a moisture content of 25% or less on wet weight basis, 12-18% is ideal.
What wood should I be using?
DRY. This means a maximum of 25% moisture content but ideally under 18% if possible.
Do not burn any wood which has been treated as this will release poisonous gases and dioxins. Do not use any driftwood as the salt content can cause irreparable damage to the ceramic cylinder and metal components. Younger softwoods and timber which has a higher moisture content will produce a greater volume of creosote and soot than dry, well seasoned hardwood.
Logs should be approximately 100mm - 120mm in diameter by around 300mm - 400mm long for your Pyroclassic IV Fire. Logs should be approximately 100-120 mm in diameter by around 200-250mm long for your Pyroclassic Mini Fire.
Dry wood is a must. To get the heat out of wood the fuel must pass through several stages. Firstly, free water that is not chemically bound with the wood is driven off – even wood at 20% moisture content still has to get rid of 2 litres of water for every 10 kilograms of wood. In the second stage the wood breaks down into the volatile gases, liquids and charcoal. Finally, the charcoal is also gasified, burning with a very short flame close to the char surface that appears to glow. In wood stoves all stages proceed simultaneously.
Wood is the most prolific worldwide, solar embedded, carbon sequestered energy source which is renewable in a human lifetime. It will provide energy when the sun is not shining and the wind is not blowing, when the outside temperature is above or way below freezing and when the electricity is not coming out of that little hole in the wall. If the abundant, worldwide timber resource is managed correctly it is the most sustainable, environmentally safe, renewable, resource we have and it has sustained mankind for centuries, providing us with warmth for the space we live in, warm water to clean with and the ability to cook food.
With the discovery of more energy intensive and easily transportable fossil fuels, wood was relegated to a lowly place in the order of preference and although it is bulky to transport it is the safest as it does not need a specially built pipeline, it won't suddenly explode or cause devastating marine pollution and with almost no refining can be used in its raw state. The closer it is used to the place where it has grown makes this an even more environmentally friendly product.
Most designer wood burners catering to aesthetic demands totally disregard the thermal conductivity of wood. Microscopic examination of wood shows the channels which carry the liquid nutrients up and down the tree; consequently the properties of wood are very different along the grain than across it. Heat moves along the grain about fifteen times faster than across it, therefore, solid wood across the grain does not conduct heat and is an effective insulator meaning it does not readily burn.
When a fire is lit, even by rubbing two sticks together, the gasification process starts and it is the combustion of these gases with air that produce heat which we see as flames and smoke. When heat cannot penetrate wood easily, i.e. across the grain, the volatiles given off are not rich enough nor hot enough to burn efficiently. Efficiency apparently is not a consideration in such panoramic appliances.
This is getting to the really nerdy bit now...
Burning of the volatile gases delivers over 60% of the heat stored in the original log but few heaters can recover the major portion of this heat as the volatiles must be over 600°C and mixed with hot oxygen to burn them. Now these are difficult conditions to meet and here’s why: if the main air supply comes from under or around the burning logs, the glowing char consumes all of the oxygen - it takes only 5cms of glowing char to consume all the available oxygen. At that point, incomplete combustion continues as characterised by increased carbon monoxide and tars which mostly go up the chimney where the unburnt volatiles deposit on the flue walls as a highly flammable, gummy substance known as creosote. It is wrong to introduce cold secondary air above the fuel as it cools the gases below their ignition temperature and now they won’t burn at all. The requirement is to introduce a highly pre-heated but variable volume of air for the different stages of combustion. This is done very efficiently by the secondary air tubes inside the Pyroclassic IV fire.
All fires consume large volumes of air in order to extract the oxygen required to burn their fuel. One kilogram of wood needs 3.7m3 of air to burn completely, although this is only a theoretical minimum for stoichiometric combustion. Such ideal combustion does not exist in real life as only some of the oxygen in that amount of air can be used and therefore 'cool fires' need some 200% - 300% excess air to get the oxygen they need. Therefore some 7 - 10m3 of air per kilogram of wood pass through the firebox cooling the core temperature inside it and cooling air below 600°C , which kills the reaction needed to burn the volatiles. In most fires the air needs of the fire make it work against itself making it inefficient and polluting, the excess air it uses only goes up the chimney with all that gas, tar and particulates. A Pyroclassic IV only uses super-heated air in its secondary burn cycle ensuring there is no cooling of the firebox and no excess air consumed.
Burning wood scientifically is done very effectively by the Pyroclassic IV freestanding woodburning fire but even the cleanest and most efficient woodburning stove needs logs which are as dry as possible to give the best output from your fuel. Check the moisture content of your wood when you buy it and then let nature do the hard work for you. Stack it off the ground in an open sided, roofed store to allow plenty of air flow around it for as long as possible or at least until the moisture content is below 20%. It’s then ready to be used in your Pyroclassic fire to give you a nice warm house right through winter in the most efficient and cleanest way possible.
Can you configure the flue to have an offset so it goes out the wall behind the fire rather than the roof?
Yes, offset bends are available for the flue systems. The best option would be to speak with a local installer who can give you specific advice about a flue system to suit your home.
Do note that a general rule of thumb is to try and avoid having any offsets in the first length of flue pipe, no more than a 45 degree angle and no more than 600mm centre to centre of the offset. Offsets do require more maintenance with cleaning etc. and can have adverse effects on the fires performance versus a typical vertical flue.
How to replace the door to glass sealing gasket
Download the instructions here - Replacing-Door-to-Glass-Sealing-Gasket.pdf
How do I refuel the fire?
Use the rake to evenly distribute the hot ember and ash along the base of the fire box, ensuring there is sufficient hot ember at the front to provide adequate ignition to the fresh fuel load. Load the fresh fuel so the logs are loaded lengthways and one end of each log is in contact with the back wall of the firebox. If you keep your fire burning under the metal air tubes which run along the top of the cylinder, this will ensure the maximum amount of heat is captured within the ceramic cylinder. As hot gases have the most distance to travel before entering the flue, this allows the whole fire to retain as much heat as possible. When raking, avoid plugging the Turboslide inlet with char or ash (this is the hole covered externally by the Turboslide below the door). Using other tools may cause damage to the ceramic cylinder, always take care not to impact the ceramic surface.
My Pyroclassic door gasket has moved out of place. What do I do?
The door to glass sealing gasket can occasionally walk along the back of the door. This happens due to the screws not quite holding enough tension on the door glass and so during the expansion and contraction process the gasket gets moved along a fraction each time.
This can be realigned by loosening the screws off and shifting it back into position so long as it’s not to stretched out. If it is damaged or stretched then it is easier to buy a new one and start again making sure to check the screw tension after a few weeks to adjust them back up to tension again. This gasket can be purchased from our Online Shop.
Can I cook on the top?
Yes you can cook on the 10mm thick steel top plate of the fire once a good fire has been established inside the fire chamber. You can use this area for all manner of cooking or warming. The cooktop oven provides better control and more versatility with cooking, which can be purchased from our online shop.
Cook top area measures 0.26m2.
What is Pyroclassic Fires' return policy?
Pyroclassic Fires is committed to customer satisfaction. If you are unhappy with your purchase for any reason, return it to our Hastings factory within 30 days in the condition and packaging you received it and we will happily refund your money.
Please note: A 20% repackaging and restocking fee applies.