masonery stoves

[mvk]

I like the idea of these and at one time wanted to build one. One of the draw backs was if you left your house for awhile it took forever to warm it up. Anyone know if they have ever been built with a gas burner included that could be fired up by a thermastat? Seems like it wouldn't be that hard but like a lot of my ideas i'm sure there are a bunch of holes in the thought. Pepole that have them around here seem to like them.
Mike

[glenn kangiser]

I don't know how you would make it pass code with the required safety devices, testing  etc. 

An experimenter with no codes may accomplish something,  but then would likely not get insurance.

[mvk]

thanks Glen
got to get used to the code stuff, never really considered it. about the idea it seems to me that I would just need a seperate fire box that was conected some how to the main chamber of the stove so as to not foul up the gas burner? Did you have code issues with that rocket stove? also thought about including a wood oven some how? There was a article on the fine home building site about how the average builder( all certified of course) had no trouble getting the bare minumun passed where as anyone who wanted to do better got to jump through hoops, Pegs comments about sheathing comes to mind (horizonal or verticule. when I was in prduction framing we always put it on on the deck(verticule) and usally butchered it. I don't see how a gas burner some where inside a couple of tons of stone, cement and fire brick would be a problem as far as the gas hookup that would just be like any other appliance I would think.
Mike

[Redoverfarm]

mvk not real sure about the gas addition but once upon a time I had a outside wood furnace with a fuel oil backup.  The main problem I had was that after a month or two of wood and then trying to get the fuel oil working when I had planned on being away was not easy.  The soot, smoke from the wood covered all the working parts of the fuel oil burner and the sensor would not work.  So what I ended up doing was to remove the fuel oil gun and cap it off.  Then when I anticipated being gone I would reinstall, bleed the line and fire it up. In my opinion it was a pain to go through. Not real sure propane would be any better with this type of application.

[MountainDon]

Glen....Did you have code issues with that rocket stove?

The rocket stove never saw an inspector and vice versa.   

[mvk]

Thanks guys
The folks that I knew that did these were before code around here. I thought that it would be a problem trying to burn gas in the same place as you said Redoverfarm so I thought that there might be a way to build seperate but connected fire boxes. maybe some kind of damper that you lifted and locked prior to turning on the gas. you would have to make sure the wood fire was out. Then some kind of temp. sensor some where in side the masonery to account for the temp lag, so that it fired at the right time. These arn't cheap either but nether are good wood stoves or back up and I like rocks. Also if I don't need stairs to  the basement it looks like it could fit right behind some of the stairs that John has in some of the plans. I also thought that if I extended the masonery through the second floor I could heat the upstairs rooms which might only be used when we had visitors and then maybe an oven. I used to work with a bunch of guys from Switzerland and you can't change your oil in your car yourself over there or thats what they told me. Should probably get in touch with some one who builds these just to see if anyone ever did this. Think if the Indians met the pilgrams with inspectors they would have went home? 

[Redoverfarm]

I am sure they wouldn't have had them for thanksgiving dinner.

[MountainDon]

It seems to me the only reliable method for being able to use dual fuels with one of them being wood, would be to have two completely separate fireboxes and two separate flues. Separate flues would eliminate the problem of having a smouldering wood fire still there when you wanted to leave and let the gas take over. Neither would interact with the other and cause any problems. I would think they could be combined in the same masonry unit.

But it all hinges on the code inspector if there is one involved.

[MountainDon]

More thinking about this... how about combustion air? Would the wood burning fireplace have a fresh air intake, doors to prevent all the warm inside air from going up the flue?

I would think if you could get the gas burner ok'd it would have to have an exterior air supply just like they demand for a gas furnace located in closet space inside the house. Or like a lot around here the furnace sits in the garage which is supossed to be sealed off from the living space.

[MountainDon]

Here's a link to some interesting info on fireplaces in tight homes. Took a while to locate the bookmark. I put it on a new topic under Referral Links.

http://countryplans.com/smf/index.php?topic=3724.new#new

[TexstarJim]

You guys should overlook my poor knowledge of wood heaters and if I am asking something that is old hat to all of you, once again, just overlook me.

Years ago somewhere on the internet I discovered a wood heater that was full of chambers that overlapped one another and the firebox was fairly small and designed only to heat the oven, then the fire went out, leaving the ambient heat of the stone\masonary, bricks, whatever........  to slowly release the heat all through the night.

You guys sort of touched on this in this thread, but I'm not sure you're talking about the same type of heater I am.  Does anyone know of the type of heater I am asking and if so, do you have a link?  thanks, Jim

[MountainDon]

Also known as a Russian Fireplace, if I'm interpreting you correctly.

http://www.mha-net.org/

http://www.hollowtop.com/cls_html/do-it-yourself/masonry_stoves.htm

http://www.adobebuilder.com/grubka-european-masonry-stove.html

[glenn kangiser]

Here are a couple oven sites.

http://www.traditionaloven.com/

http://heatkit.com/html/bakeoven.htm

The problem I see with the gas and wood combo is that the gas stoves need safety devices.  If they don't have them and unlit gas gets to hot embers - it could raise the roof.  Gas is easy and safe with proven safety devices but dangerous without them.

[MountainDon]

Questions for you mvk...

What is the size of the place you want to keep warm?

How often do you expect to be absent and for how long?

What utilities do you have? electric, gas, propane......

Considering some of the headaches involved you might want to consider a more conventional system for backup heat. Might also make your insurance company happier. 

[mvk]

thanks guys
Don your answers first: 20x30, 24x36, 1 1/2 storeys with bedroom addition 14x16? maybe just the downstairs heated full time.
unless I hit the lottery this will be our full time house. we will leave for maybe a week or two in winter and several long weekends.
will have electric and probably propane.

I have always had these refered to as stoves not fire places though the ones that I see on the sites you posted look like fireplaces with the glass doors etc. I knew someone who built one in the mid seventies and was in another house that had onethat was owner built a few years later. They really felt good to be in. They did have a pipe for outside air. I was told that you only needed a small arm full of wood per day and once you had all that mass heated you had complete combustion and not much smoke.

I kind of figured that you would need seperate fire boxes but if you needed seperate flues I think you would loose the benifts of the design. Guess what I was thinking was how much gas is a small armfull of wood in btu's. Also maybe would gas work full time in twenty years from now if we didn't want to mess with wood.

Glen about safety I don't know what that would entail? some kind of shut off if there was unlit gasses in the fire box. Kind of thought that I would get a old gas space heater and take it apart and use the componets some how, safety devices included, and all you smart guys on this site would tell me how to do it!

Guess that if this was a good idea it would be already done. Thanks again, love this site. Mike

[TexstarJim]

Thanks Don, that 2nd link shows the diagram of the type of fireplace I was wondering about.  Seems like they would be very difficult to build, but well worth the effort. 

[MountainDon]

....thinking was how much gas is a small armfull of wood in btu's.

Go here for btu content of some different fuels

http://countryplans.com/smf/index.php?topic=2198.msg29641#msg29641

Nat Gas is not on the list and neither is propane, but can be googled. I have to run or I do it. Maybe later

[glenn kangiser]

Clothes driers have safety devices built in and come with natural gas or propane flavors.  I have thought about using one of them for other things.  I haven't experimented with them though.