Russian Fireplaces(Masonry Heaters)

[FallbrookFarmer]

Have been reading all the posts about wood heating, and remembered reading about Russian fireplaces , seems to be a great idea, build a small hot fire in a firepit and then have all the hot exhaust gas run thru a series of chambers that store the heat, and slowly radiate it back out over 12-24 hours.
Question? Has any ever done something similar with a wood stove venting into a series of masonry baffles, storing the heat without having to build the firechamber portion? Thanks for any ideas.

 

[forgeblast]

mother earth news had an article on it, and some people sell plans for it. There is a masonary association that also has a how to. It looks like a lot of work to build one but the thermal mass of it would hold a lot. Cleaning it would not be fun with all the twists and turns.
russian fireplace plans - Google Search
shows a lot of the links.

 

[Lloyd_E]

A little bit closer to you. This local company installs in new construction as well as old...

Untitled 1

Old concept that is new again.

Lloyd

 

[jake98]

Cleaning it would not be fun with all the twists and turns.
russian fireplace plans - Google Search
shows a lot of the links.

I worked for a mason when I was young that built his, he said it had a cleanout on opposite sides, every other one.

 

[Slackdaddy]

A metal fire box would not work.
The whole concept of a Masonry Heater is that you build a HOT fast fire and store the energy in the masonry mass. The hot fire burns off almost all the gasses, producing almost no smoke/cresote.
The temp needed to atain this type of burn would melt a metal stove.

Slack

 

[dave1949]

A metal fire box would not work.
The whole concept of a Masonry Heater is that you build a HOT fast fire and store the energy in the masonry mass. The hot fire burns off almost all the gasses, producing almost no smoke/cresote.
The temp needed to atain this type of burn would melt a metal stove.

Slack

That's the way my masonry stove works. It will have flames 2-3 feet long curling into the firebox exit passages. That's what is supposed to happen.

To encourage that type of burn, the manufacturer recommends sticks 4" diameter or less. My experience agrees with that recommendation.

I get just about zero creosote and only fly ash accumulation in the passages inside the stove after a season of burning.
Dave.

 

[wrangler6831]

Here is a version manufactured of soapstone in Finland. If I remember correctly they start around 5 or 6K for the smaller models but are supposed to be really efficient.

Tulikivi Fireplaces Natural stone Soapstone Household ceramics

The link gives you an animation of what happens inside the fire box.


Rich

 

[dave1949]

Here is a version manufactured of soapstone in Finland. If I remember correctly they start around 5 or 6K for the smaller models but are supposed to be really efficient.

Tulikivi Fireplaces Natural stone Soapstone Household ceramics

The link gives you an animation of what happens inside the fire box.


Rich

This link will take you a series of pics showing our Tulikivi being built:
Betts Family Photo Gallery - chimney and stove

It cost $18,600 installed in 2006. Has a bake oven on one side and firebox on the other. Gotta tell you the price brought tears to my eyes, (think of the tractor toys!) but my wife fell in love with them and we have been equal partners for 39 years now. They are high quality and work very well. Since they are built on-site, it's a one-time decision; you will not be posting it on craigslist

I believe I wouldn't consider one as a primary heat source unless you have a very well insulated, tight home. They excel at putting out low level heat for a long period of time (20-24 hours on one burn), hence they will not keep up with heat loss in a drafty or poorly insulated house. The BTU ratings tell the story. For us, it works quite well, but I still see at least a grapple when I look at it
Dave.

 

[FallbrookFarmer]

Thanks for the replies,
My thinking was that because the exhaust gases are so hot, that they would heat the masonry mass of the baffles, and that would store the heat, but I now see that error it that.
Thanks.

 

[dave1949]

Thanks for the replies,
My thinking was that because the exhaust gases are so hot, that they would heat the masonry mass of the baffles, and that would store the heat, but I now see that error it that.
Thanks.

I think it would be tricky to get a hybrid metal stove/masonry stove working well. One thing you can do to get some of the best of both is to surround a standard wood stove with a lot of masonry mass. Natural stone, concrete, or a combination. With an air space between the stove and masonry of 12-18 inches maybe? As the stove burns, the masonry will absorb heat without affecting flue temps, creosote formation, etc. As the stove cools off after burning, the masonry mass will give up heat to the room air for quite a while.

The hottest point on the outside surface temperature of my Tulikivi reaches about 150* on a very hot burn and around 135* on a regular firing - if that helps visualize. Of course, the inner stone around the firebox is much hotter and that heat migrates to the surface over time. Since the stove weighs 3 tons, that's a lot of heat stored to migrate out.

Keep in mind the basic law of thermodynamics: heat transfers from a warm object to a cooler one, and the greater the temperature difference is between the objects, the faster the heat transfer occurs.

Dave.