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How much does it cost?
To download the RRP price list of our Pyroclassic wood fire and accessories, click HERE.
When and how should I clean the flue?
Pyroclassic fires are renowned for burning very cleanly when dry fuel is used but you should still always clean your flue once a year. This is often a requirement for many insurance companies.
Keeping your 100mm flue pipes clean will help eliminate the risk of a flue fire. Your flue is also a great indication of how your wood fuel is performing. If the pipes are clean then the wood is good, if the pipes are filling up with carbon, creosote and tar deposits then you may need to revisit the operating instructions and refresh yourself with how to create a cleaner burning fire.
The easiest way to clean the flue is by placing a deep baking tray or similar under the base of the flue and sweep the flue down into this, this stops all the debris from falling into the top chamber and requiring vacuuming out.
The build-up around the wetback is best removed by hand. The wetback can be knocked out of alignment if it is moved when the creosote is being cleaned off so be careful as this can cause the constant rise to be knocked out of alignment and can result in water hammer developing in the system.
Why have Pyroclassic fires dropped from No. 1 on Consumer NZ tests on their last report?
Consumer Magazine recently changed the way fires are rated. This has caused some issues across the industry as what were considered the 'best' fires are now not rated near the top...like the Pyroclassic IV. They have changed the weightings of their review to focus more on price for output over emissions and efficiency as they believe this is more in line with what the customer wants.
This has resulted in a list which is more about heat output for dollars spent rather than which fires actually perform the best. It also makes no provision for servicing costs, warranty duration or expected life of the appliance and its components.
The statement we have printed in our marketing material - 'Consistently chosen as the top pick for wood fires in all Consumer reviews' refers to the consumer reviews across various formats in NZ, Australia and the UK over the last 30 plus years including true consumer feedback.
How often do I need to clean out the ash?
The chamber in the Pyroclassic IV can operate with or without ash in it. However, it is preferential to empty this out every week or when the ash builds up to the extent that it could inhibit the operation of the Turboslide.
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.
Why is smoke coming from my Pyroclassic fire into my room?
There are a few reasons why this could be happening:
- Negative pressure in the room - this can be caused by a household electric exhaust fan or severe pressure difference in a windstorm. Open a window to equalise the pressure.
- Severe down draft due to surrounding structures, hills, trees or roof layout.
- Most commonly, this is an indication your flue is blocked. Clear the obstruction and investigate the cause. Check the moisture of your wood and make sure you are burning good, dry wood. The flue pipe can block very quickly if you are burning wet or gummy wood. Make sure you are using a reliable chimney sweep as the Pyroclassic is different from other wood fires.
Download down draft troubleshooting info HERE.
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.
The front of my Pyroclassic fire has developed smoke stains on the panel. What can I do?
Depending on how extensive the marking is you may be able to remove it by using a light abrasive car polish. Remove the panel and place it on a kitchen bench as this will be much easier than doing it on the fire. Please be careful of the gasket if it's still attached to the back of the front panel when removing and replacing it. Please avoid handling the panel when hot. Always make sure the panel is cold.
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.