Mid-Atlantic Masonry Heat - Warms you like a hug
Masonry Heater technology is based on the principle that after the flue gases leave the firebox they pass through up-draft and down-draft heat exchange channels, which absorb most of the heat energy from the flue gases before they exit out the chimney. The heat is stored in the substantial thermal mass of the masonry heater. This technology is not allowed with natural gas or propane. For example, if there were a gas leak in the system, and then ignition, an explosion would result. A gas or propane heater usually includes some type of heat exchanger which blows hot air into the room, as opposed to a masonry heater which stores the heat energy and then radiates that heat slowly, over an extended period of time after the fire is out, primarily affecting the mean radiant temperature of the room as opposed to the air temperature.
A Tulikivi Soapstone Heater can be equipped with electric elements, located in the heat exchange channels, controlled by a thermostat, that provide an alternate heat energy source to wood. It is possible to switch back and forth between the two methods. (hyperlink to electric element page?)
A Tulikivi heater can be retrofitted to an existing fireplace but the thermal mass of the heater must be placed in front of the fireplace and not in the existing firebox for a number of very good reasons. First, the amount of soapstone thermal mass required for adequate heat storage and the configuration of the heat exchange channels, in even a small heater, would easily exceed the amount of space in virtually all residential fireplaces. Second, even if the firebox space were large enough, placing it in an existing firebox would significantly reduce the impact of the heaters infrared radiation to the room. Finally, as is often the case, if the firebox is outside the envelope of the living area, then a great deal of stored heat is lost to the outside.
Just as with any hearth stove or wood burning insert the existing chimney may be able to be utilized, however, caution must be taken to insure it is in good condition and properly sized for the wood appliance to be installed. (hyperlink to retrofit page)
Unlike many wood-burning stoves, the Tulikivi heater is not finicky. Any seasoned wood will burn well. In Finland these heaters are burned with softwoods like pine and birch. There are not many deciduous hardwood trees near the arctic-circle. Because softwood is less dense than hardwood it weighs less per unit volume, but the energy per pound remains the same. A Tulikivi fireplace with an efficiency rating of 85% has a heating potential of 6272 BTU's per pound of wood. This means that 16 pounds of dry cordwood burned in a small Tulikivi fireplace would provide 100,354 BTU's of heat energy for the home. Tulikivi fireplaces with a larger thermal masses can burn, store and then radiate over 300,000 BTU's of home heating energy from a single firing of approximately 55 pounds of cordwood. (link to wood burning page)
Color variation ranges from a greenish/gray background to a black background with some green highlights in the marbling of the slabs. The marbling appears more pronounced in the darker slabs due to the white versus black contrast. The ambient light in the room and the decorating colors also affect the caste of the slabs background and/or highlights. Once oiled, the undertones are brought forward and darkened.