http : / / www . inspirationgreen . com / masonry - heaters . html ( 사진 ) Masonry HeatersAlso known as masonry stoves , kachelofens , Russian fireplaces , Finnish fireplaces , Swedish stoves , tile stoves , contra - flow fireplaces , radiant fireplaces and mass - storage fireplaces . Inside , masonry stoves burn hotter than metal wood stoves and their winding maze of flue ( baffles ) warms the surrounding masonry , which then emits heat for 18 to 24 hours . The temperature can reach 2000 degrees inside some masonry heaters ( vs 700 inside a metal stove ) , yet they stay comfortable to the touch on the surface . At these high internal temperatures , the hydrocarbon gases ignite , leaving very minimal pollution . When burning wood , about 30 % of the generated heat is supplied by the wood solids and 70 % of its heat is contained in released gases . If the volatile gases are not fully combusted , they escape as wasted heat and polluting particulate emissions . Igniting and then drawing the heat out of the combustion gases turns almost every ounce of wood into energy . A slow burning , low temperature , low oxygen fire produces tar and hydrocarbons , a fast , hot , air - fed fire burns the pollutants up . Add a storage battery ( the masonry ) and you have a very efficient , non - polluting heating system . A metal stove gives out its heat rapidly , thus never allowing the inside combustion temperatures to achieve the 1100 degree F plus needed to ignite all the gases . Because the stored heat radiates slowly from the masonry , it is only necessary to light a fire once a day in most circumstances . In really cold conditions , you might need to light two fires a day . Metal wood stoves must be tended to continually and fluctuate from peak high temperatures , to no heat , when the fire is out . If you tamp down the flue on a metal wood stove you increase the emissions of pollutants as the combustion of the wood is incomplete . A masonry heater always burns wood at the highest heat , if you desire less heat , you simply use less wood . In a well insulated home , a masonry heater will use 1 / 5 th ( or much ) less wood , then a home heated with a metal wood stove . All well - designed masonry heaters easily outperform the highest rated EPA metal wood stoves . And like a wood stove , a masonry heater can exhaust through a metal flue pipe . The masonry stove has been around in many different forms in almost all ancient northern cultures , from the 7200 year old Kang bed stove in China to the Hypocaust in ancient Rome . In northern Europe , 500 - 600 years ago , a long - lived cold spell caused local wood to become scarce and masonry heaters became common due to their efficiency . In the past hundred years dirty coal , then oil replaced the masonry heater . Wood is a renewable resource and absorbs CO 2 as it grows . Burning releases about the same amount of carbon monoxide , carbon dioxide and methane as would occur if the wood were decomposing naturally on the forest floor . * Yet wood is a sustainable energy source , only when proper wood lot management is employed and when its energy is extracted efficiently and cleanly . Although these effective heaters were and are still popular in Russian and northern Europe , the United States has never had a wood shortage , so the masonry heater has been pushed aside for the wood guzzling metal stove . Considering that masonry heaters are efficient and emit little pollution , the United States should take a closer look . Surround your heater core with stone , brick , stucco or tile . Although kits are available , this is not a project for one new to masonry ( see resources section ) . In the meantime , before I build one , I am simply going to pile large rocks around the wood stove . = = = = = = = = = = ========================= Mark Twain on the Kachelofen . .. from " In Europe and Elsewhere " 1923 . " Take the German stove , for instance - where can you find it outside of German countries ? I am sure I have never seen it where German was not the language of the region . Yet it is by long odds the best stove and the most convenient and economical that has yet been invented . To the uninstructed stranger it promises nothing ; but he will soon find that it is a masterly performer , for all that . It has a little bit of a door which you couldn ' t get your head in - a door which seems foolishly out of proportion to the rest of the edifice ; yet the door is right , for it is not necessary that bulky fuel shall enter it . Small - sized fuel is used , and marvelously little of that . The door opens into a tiny cavern which would not hold more fuel than a baby could fetch in its arms . The process of firing is quick and simple . At half past seven on a cold morning the tender brings a small basketful of slender pine sticks - say a modified armful - and puts half of these in , lights them with a match , and closes the door . They burn out in ten or twelve minutes . He then puts in the rest and locks the door , and carries off the key . The work is done . He will not come again until next morning . All day long and until past midnight all parts of the room will be delightfully warm and comfortable , and there will be no headaches and no sense of closeness or oppression . In an American room , whether heated by steam , hot water , or open fires , the neighborhood of the register or the fireplace is warmest - the heat is not equally diffused throughout the room ; but in a German room one is comfortable in one part of it as in another . Nothing is gained or lost by being near the stove . Its surface is not hot ; you can put your hand on it anywhere and not get burnt . Consider these things . one firing is enough for the day ; the cost is next to nothing ; the heat produced is the same all day , instead of too hot and too cold by turns ; one may absorb himself in his business in peace ; he does not need to feel any anxieties of solicitudes about the fire ; his whole day is a realized dream of bodily comfort . America could adopt this stove , but does America do it ? The American wood stove , of whatsoever breed , it is a terror . There can be no tranquility of mind where it is . It requires more attention than a baby . It has to be fed every little while , it has to be watched all the time ; and for all reward you are roasted half your time and frozen the other half . It warms no part of the room but its own part ; it breeds headaches and suffocation , and makes one ' s skin feel dry and feverish ; and when your wood bill comes in you think you have been supporting a volcano . " Via , kachelofen - usa . net = = = = = = = = = = = = =========================