Burning Questions

What is the difference between a steel woodburner and a Tigchel heater?

The ”stone” Tigchel heater will never get too hot, but remains "touchable warm". That is in contrast with a steel heater, which releases the heat very quickly and can become very hot!  
That is because the stony mass of the Tigchel heater will evenly heat up from within, acting like some kind of heat accumulator. The thick stony walls (3 layers) store 85-90% of the heat and slowly release it - all day long. In that way, the unit releases a mildly dosed amount of radiant heat. In most cases, a mildly dosed heat output will be sufficient for most of the winter season.
A steel woodburner does not have this feature. The only way of reducing the heat is to choke the fire, in which case the wood will start smouldering. Such smouldering (choking the fire) is a very bad stage in the wood burning process. It will cause the atmospheric emission to rise to unacceptable levels (inside the home there is even a risk of carbon monoxide poisoning; also, tar building up inside the chimney may ignite a fire and the outside air is polluted by clouds of smoke).
The mild heat of the Tigchel heater is more in line with the need for warmth and safety, and ideally suits the energy-efficient home. Thanks to their very low atmospheric emission, the heaters are also much more environmentally friendly than steel woodburners in urban areas.
A steel woodburner can only operate efficiently is cases of a large demand for heat and where large logs of hardwood are being used. In contrast, the Tigchel heater - with its characteristic wood burning properties - can produce just as much heat (for every kg. of fuel) from bone-dry softwood.

Almost every new woodburner claims to be highly efficient. Is such a claim correct? How can I get a better understanding, and what does "high efficiency" actually mean?

More stringent rules and regulations in Europe in the last 20 years have spurred the demand for more efficient woodburners. One of the consequences is the introduction of the so-called efficiency label. Whether or not all heaters (in the A category) are actually achieving a high-efficiency label is often a matter of theoretical efficiency.

What are the savings on fossil fuels if I switch over to green energy?

"Green energy" comes in different forms and for different purposes.
Heat - for heating homes; and electricity - for running appliances and for lighting.
At this point in time, electricity consumption from fossil fuels results in the emission of 2177 kg. CO2 a year for the average household. In other words, switching over to green energy will save the emission of 2177 kg. a year for the average household. In comparison: the consumption of 824 litres of petrol or 1209 cubic metres of natural gas also results in the increase of 2177 kg. CO2.
Using natural gas for home heating (2000 cubic metres on average) equates to the increase of CO2 of approximately 3600 kg. However, using biomass (dry wood) for efficient home heating will reduce the CO2 emission by 3600 kg. For heating purposes, directly burning wood (i.e. burning at places where heat is required) will give most savings.

Would a Tigchel heater (accumulating heater) really be suitable in a climate like ours?

The Tigchel heater originates from continental countries where large fluctuations in temperature is common. It is therefore meant to level out any large fluctuations in temperature. Also in countries with a moderate climate and less extreme fluctuations in temperature, the evenly spread heat of the Tigchel heater is a very comfortable way of home heating. Under these circumstances, a steel woodburner would soon be producing too much heat. During winter, a Tigchel heater will give you longer enjoyment from the generated heat.

Can I in fact see the flames?

Yes, the doors are fitted with glass, so you will be able to enjoy the relatively short period of dancing flames. With clean wood burning, the glass will also remain clear for much longer.

Would I be able to turn my open fire into a Tigchel heater?

It would not be fair to say that any open fire can be modified. After the entire fireplace has been removed, a Tigchel heater or even a real Finoven can be built on the existing foundation. The existing flue gas discharge channel can also be used in many cases. Following the modification, you will enjoy all the extra benefits, both in the sense of wood consumption and in heat comfort.

Can a Tigchel heater be connected to any chimney?

Our experts will assess the situation and advise on any improvements, if so required. For instance, the chimney pipe diameter must be at least 150 mm. Tigchel heaters can be fitted with a flue connection at the back (at various levels) or on the top. In other words, for the Tigchel heater the connection point is of no concern.
If for any reason the construction of a new chimney would appear to be too hard, the Tigchel heater can also be easily connected to a wall grid with a fan. In that case, the fan will create the required chimney draught. It can be mounted on the outside wall or on the roof. A power point near the heater is required though. When we call in, we will go over all these options together with you.

Will I first have to insulate my home?

If you can..., absolutely!!! An insulated home will pay off with more comfort and the highest financial returns. After completing the insulation work, you decide on the most suitable Tigchel heater for your low-energy home. The effect of the Tigchel heater in your home will definitely be (much) greater and/or you will greatly reduce the amount of wood needed to keep you warm in winter.

Which are the preferred types of wood to be used in a Tigchel heater?

In principle all types of wood can be used, AS LONG AS THEY ARE ABSOLUTELY BONE-DRY.
The actual efficiency of combustion of all types of wood is by weight. Dry and untreated demolition wood, as well as disposable pallets, can also be used. For more information, see also the PDF Heating Guide

Can I use any fuel other than wood in a Tigchel heater?

Thanks to the use of fireproof concrete, other SOLID fuels, such as coal, briquettes and peat, can also be used in Tigchel heaters. The efficiency of combustion of coal in relation to wood is even very high! Tigchel heaters cannot be used for natural gas or other types of gas. The gas inspection authorities in the Netherlands will not allow the installation of gas burners in Tigchel heaters without prior (and costly) testing. The Tigchel heater has been specifically developed for burning wood. Burning wood is better for the environment than burning gas, according to a scientific study conducted by the NIBE in Baarn (NL). Gas is often more expensive than wood for home heating.

Can floor or wall heating be connected to a Tigchel heater?

All Tigchel heaters and Finovens are producing radiant heat. This is a direct heat medium, creating a warm floor, a warm ceiling and warm walls around the heater. The medium is very efficient, absolutely free of charge, and the (silent) power of the Tigchel heaters.
See also the video clip on Radiant heat.

A Tigchel heater/Finoven can also be connected to floor of wall heating. That is the case if the heater is fitted with one of our hot water systems. Model 1, 3 and 4 are made for low-use capacities. Model 2, the Kyoto heater, may also serve as a fully wood-fired central heater.

Can I have the fire going and leave the fire door open ?

THIS SHOULD BE STRONGLY DISCOURAGED!!! That is because the unique operation of the nozzles in the furnace will lose its effect and the chance of smoke escaping to the living areas and beyond is as big as when an open fire is used.

How much time will it take to build a Tigchel heater or Finoven?

A Tigchel heater is often built in half a day. Taking into account some extra jobs that may come up, it can usually be done within one day.
A "custom-built" Finoven will take several (3-7) days. It all depends on the size and the design.

What is the delivery time?

Approximately 8 weeks for a -removable- Tigchel heater. A "custom-built" Finoven can often be completed after 2-3 months. All depends on the design and the chosen materials. In winter, the delivery time for any project may take about 3 months or more.

Will a Tigchel heater or Finoven need regular maintenance?

Tigchel heaters and Finovens require very little maintenance. Every 2 to 5 years we may come and inspect the heater and vacuum-clean the interior, if so required. We recommend having this done every three years. Much depends on how the heater has been used. However, the flue gas discharge channel (chimney) should be inspected and swept once a year. All the resulting deposits are subsequently to be removed.

Will a wooden floor be able to hold the weight of a Tigchel heater?

A Tigchel heater weighing between 600 and 800 kg. can be installed onto a wooden floor in most cases. However, much depends on the condition of the floor, of course. If necessary, a few piles underneath the floorboards may provide sufficient support for the installation of the heater. Heavier heaters will require a concrete surface, or else we provide a foundation before installing the heater.

Will a Tigchel heater require separate air supply?

In many older type homes, putting a window ajar will be enough to supply the heater with the air it needs (in that case, burning wood and ventilation will happen simultaneously).
In homes with mechanical exhaust systems (ventilation based on underpressure), a separate air supply for the heater would be recommended.
Manual ventilation is also possible in super modern homes equipped with a balance ventilation system; an open window or air grate may give the heater a sufficient amount of air. After the wood has been burnt up, the window or grate can be closed and the balance ventilation will resume its ventilation task.

Can you come and see us?

We cannot answer this question with a definite "yes" since we have to consider a number of factors. Much has to do with the often valuable travelling time and additional car expenses. In the event that you are well advanced in your plan to purchase a Tigchel heater or Finoven, and if the assessment of the chosen location is part of your consideration, we will be happy to come and see you in person for advice, free of charge. However, if your interest has been aroused through our web site or by passionate existing owners without much in-depth guidance, these visits would only (unnecessarily) increase the price of the heaters. In that case we suggest you first come to our show room, where you will see a range of models in various colours in action. In our show room you will be able to not only see the heaters, but also experience the warmth they produce - without any obligation to buy, of course. Also, at your request, you will be able to talk to one of our staff for information and advice. For detailed enquiries we suggest you avoid busy Saturdays and give us a few days' notice, so we can spend all our attention to your questions and concerns.

If so, can you also give us a quote straight away?

Yes, we can give you immediately an approximate price. But we suggest you first consider the various options brought up during the talk with our staff. A quote will be made after all details have been processed. If you have already made up your mind, you will receive our quotation in writing within one week.

Wood burning - is that also labelled as green energy?

Yes it is. Wood is no fossil fuel, like natural gas, coal or oil. CO2 is also released during the combustion process of wood, but it equals the amount the trees have absorbed during their life. In other words, burning wood will not result in an increase of CO2. However, we must be sure that wood for lighting fires will not (no longer) serve any other useful purpose, that we look after our forests in a sustainable manner, and that primeval forests are left in peace. A large-scale cultivation of new trees is the best way to achieve a reduction of CO2 in the atmosphere. Young trees absorb large amounts of CO2 during their growth. Uneconomic plots of land can easily be used for the cultivation of fast-growing trees to produce firewood in the future. Mature trees absorb only a small amount of CO2, so it would make sense to use the trees for this purpose. In this way the CO2 absorption and release has come full circle.

What can go wrong?

1.  The expectations of heat output are often (too) high. Many believe that such large woodburners release much heat and are particularly meant for large spaces. WRONG. On the contrary, a heat-accumulating woodburner gives a very tempered heat, a kind of friendly, modest heat, evenly released all day long!

2.  Insufficient insulation. Heating older homes and farmhouses to a comfortable degree in the middle of winter demands a lot of energy. An accumulating woodburner will produce only a very tempered heat and has insufficient capacity for this kind of dwellings. In those cases, comfortable living and economical fuel consumption depend on proper insulation. Alternatively, during some cold winter seasons an extra central heating gas boiler or other additional source of heating may be required.

3.  Attempts are made to overload the heater or accelerate the heating process. It is impossible to boost a woodburner which is specifically made to retain heat for long periods of time. Even to have the fire going over a prolonged period against the recommendation will result in only little extra heat, while the heater and the flue gas discharge channel are put under extra stress. Much better to allow the heater a full day for the release of heat it has stored.

4.  Overfilling the furnace. An overfilled furnace will prevent full combustion and create too much smoke. A half-full furnace will usually do the job. With a few logs in the back (for the second combustion round), the required heat has been achieved and full combustion is still retained. The ideal amount of wood for the Tigchel heater equals to one per cent of the weight of the heater. The Finoven requires only 1/150 part of its weight in firewood. Measure the required amount of wood only once for future reference. Weighing is paying, but guessing is messing. (The weights of the heaters are shown in the appendix "Technical specifications").

5.  After several years of storage, the wood is still not dry enough. Wood with a moist content in excess of 20% will give poor results for hot combustion and the heat produced can also be disappointing. A hissing sound indicates too much moist in the wood (watch the moist escaping from the burning wood in the form of foam, as if it is boiling). A good-quality moist content meter can be a useful aid; check the wood from time to time. For more information, see the chapter on Wood Preparations in the appendix.

6.  Finishing the drying process indoors. Finishing the drying process of wood indoors is not recommended (there is a risk of bringing in any insects hibernating in the bark that will awake when the temperature is rising). Make sure the drying process is completed outside until the moist content has dropped below 20%.

7.  Finishing the drying process in the heater. In spite of many warnings, some people still persist in finishing the drying process of (wet) wood in the afterglow of the heater. WRONG! There could be a risk of spontaneous and out-of-control combustion of the wood, or even a real gas explosion! Having escaped from such disasters, the moist in the wood will still cool the heater down, resulting in a lower start-up temperature the next time you wish to light the fire. No matter what will happen, it won't do you any good. If you are not successful in completely drying the wood in an outside area, you'd better stick to your old gas heater for one or two more years.

8.  Burning on a layer of ash. The persistent myth of “nothing can beat lighting a fire on a layer combustion ash" is still doing the rounds. WRONG! A layer of ash has an adverse effect on the combustion of wood in an accumulating woodburner. Many years ago this practice was common in primitive fireplaces, but people in those days had little knowledge of heater efficiency. In modern times we know that ash is a waste product and that waste products should be removed from time to time to retain a healthy ‘metabolism’. Regular removal is recommended.

9.  A big fire is required to start up a heat-accumulating heater. WRONG! A big fire can never be used in an efficient manner. A big fire is created when the flames are spreading fiercely across a large surface of the firewood. This may be caused by: a) overfilling the furnace; b) too many thin pieces of wood; c) the wood containing too much resin; or d) a combination of the above.