Wood Stove/Masonry Heater Hybrids, Combos

[qwee]

Sean in the woods, would you have considered one of these mini-meat masonry heaters when you were deciding on which way to go? I'll be the salesman. (You enter the store and a sales person approaches you) We have this Kube 4-2 masonry heater right over here. Let me tell you about it. It weighs just over 1000 pounds. It has chambers above the firebox. Of course it is beautiful and made of soapstone.

You can put it together yourself in an afternoon - it uses metal splines. Also besides the glass door you can order side glass viewing panels - as many as you want. Cost is $6,000.

So would you have been interested? (You probably would have needed to anchor in a couple of beams in your basement to provide extra floor support).

 

[SpaceBus]

I still feel like the firebox is too small for most American sized homes in cold climates, but they do look very nice.

 

[begreen]

Sean in the woods, would you have considered one of these mini-meat masonry heaters when you were deciding on which way to go? I'll be the salesman. (You enter the store and a sales person approaches you) We have this Kube 4-2 masonry heater right over here. Let me tell you about it. It weighs just over 1000 pounds. It has chambers above the firebox. Of course it is beautiful and made of soapstone.

You can put it together yourself in an afternoon - it uses metal splines. Also besides the glass door you can order side glass viewing panels - as many as you want. Cost is $6,000.

So would you have been interested? (You probably would have needed to anchor in a couple of beams in your basement to provide extra floor support).
View attachment 270652

Wait, it costs $6000 and you have to put it together yourself like an Ikea kit?

 

[chipsoflyin]

Makes the PH seem like a bargain at 4000.00

 

[SpaceBus]

Makes the PH seem like a bargain at 4000.00

What's the weight on the PH? It probably comes close to some of these mini masonry heaters.

 

[begreen]

Our stove is close to 600# and the PH is 700#.

 

[qwee]

The salesman said it took him an hour to put together. It might be too small for American homes but this is an unknown. You probably wouldn't want to burn it like a typical masonry heater - one fire a day. Maybe 2 or 3 fires in cold weather. The Norwegians appear to prefer these little mass heaters to typical wood stoves - and they build Jotuls which are one of the finest made wood stoves.

Scandinavians are way more about doing things the green way than are North Americans (ie ~50% EVs in Norway). This may be why they like these little mass heaters so much. And, maybe they build their houses smaller and with more insulation. For whatever reason they seem to always follow the best path. They do things long-term, not just for immediate short term gratification.

 

[SpaceBus]

The salesman said it took him an hour to put together. It might be to small for American homes but this is an unknown. You probably wouldn't want to burn it like a typical masonry heater - one fire a day. The Norwegians appear to prefer these little mass heaters to typical wood stoves - and they build Jotuls which are one of the finest made wood stoves.

Sounds like a European style tall skinny stove with some additional masonry mass, which would probably be nice in a smaller European home for softening the heat. Most Americans find the tall skinny stoves too small and require too many loads per day. When we bought our very European 2b Classic the salesman told us he didn't think it would ever sell. It's a tiny European stove, but it fits our tiny saltbox. Our cookstove is also European, but from a different region, and it has very little mass.

 

[Sean in the woods]

Sean in the woods, would you have considered one of these mini-meat masonry heaters when you were deciding on which way to go? I'll be the salesman. (You enter the store and a sales person approaches you) We have this Kube 4-2 masonry heater right over here. Let me tell you about it. It weighs just over 1000 pounds. It has chambers above the firebox. Of course it is beautiful and made of soapstone.

You can put it together yourself in an afternoon - it uses metal splines. Also besides the glass door you can order side glass viewing panels - as many as you want. Cost is $6,000.

So would you have been interested? (You probably would have needed to anchor in a couple of beams in your basement to provide extra floor support).

No. It is not large enough for our house. The amount of mass is not enough and the firebox only holds a maximum of 6 pounds of wood. Math tells me that the BTU input to the system is not enough.

Also, is your spell check changing the term “mini-me” to “mini-meat”? Searching the web for the term “mini-meat” comes up with nothing relevant.

 

[EatenByLimestone]

I was having trouble with that last night with my T5. It was upper 20s. I n

Our stove is close to 600# and the PH is 700#.

You got me curious. I looked up the T6 weight and it's 585lbs. The Summit LE is 440lbs. That's 145lbs of cast iron.

Do you think there'd be a market for heavier side panels that would bring the weight up to 700 or 800lbs? The panels would probably need to be supported by the floor, but I don't think that'd be a deal killer.

The cast iron, as it is now, really changes the nature of the stove. 200lbs more of cast iron could really turn it into a gentle giant.

 

[qwee]

Also, is your spell check changing the term “mini-me” to “mini-meat”? Searching the web for the term “mini-meat” comes up with nothing relevant.


I always thought mini-me was mini-meat from that Austin Powers movie - 1/10 the size of Dr. Evil. These little mass heaters are about 1/10 the size of a big masonry heater, so that is where the name came from. If I ever decide to build masonry heaters for others I'll call my business, "Mini-Meat Masonry Heaters", or M&M&M Masonry Heaters. They won't be these little ones, though. And I'll make sure each one has a bio/eco firebox (unlike mine).

 

[begreen]

The salesman said it took him an hour to put together. It might be too small for American homes but this is an unknown. You probably wouldn't want to burn it like a typical masonry heater - one fire a day. Maybe 2 or 3 fires in cold weather. The Norwegians appear to prefer these little mass heaters to typical wood stoves - and they build Jotuls which are one of the finest made wood stoves.

Scandinavians are way more about doing things the green way than are North Americans (ie ~50% EVs in Norway). This may be why they like these little mass heaters so much. And, maybe they build their houses smaller and with more insulation. For whatever reason they seem to always follow the best path. They do things long-term, not just for immediate short term gratification.

It's an attractive, small to medium sized stove with a modest heat output (3-7 kW) that would be good as a room heater. Based on my limited experience in Scandanavia, they keep their rooms cooler and often only heat by area, not the whole house. It's not uncommon for them to keep the house around 65º and wear sweaters. Many of their stove designs are based on this. Some companies like Morso don't make large stoves at all. Frugal folks in the UK run even cooler houses in the winter.

 

[qwee]

Interesting. I think I would only need one of these mini-me heaters for my house (passive solar, high insulation, and small), but I could be wrong.

 

[SpaceBus]

7kw is less than the smallest UL/EPA listed stoves in the US, that I know of anyway. Maybe a small mass heater would work well in a tiny house to have a long time between loading and not overheat the space?

 

[begreen]

Looks like the Kube 5 might be 12kw output. My only concern for a passive solar house would be overheating in the scenario mentioned earlier. With the small stove, it may not be a major issue, as long as windows can be opened.

 

[chipsoflyin]

What's the weight on the PH? It probably comes close to some of these mini masonry heaters.

Shipping weight was 811 lbs. Their site says 700 lbs. So I would guess somewhere in between

 

[St. Coemgen]

St. Coemgen thanks for the real world info. How does your neighbor with this small mass burner use it? Does he just keep feeding it wood (like a wood stove) when it gets cold?

A real mass heater uses a fast, hot burn (unlike a wood stove). So she does a hot fast burn. But the stove mass is too small to heat the house for very long. So has to another fast hot burn. Repeat.

Mass heaters require a lot of mass to absorb a lot of heat, which is slowly release over time. Our house did not come with a mass heater ... actually that was unusual here as most house have them, and my wife really wanted one (she is Hungarian, and grew up with these types of stoves). So we asked around, contacted static engineers and mass stove masons, and they all said the same thing... because our house living area actually sat above our rather large wine cellar, the mass heater needed to heat our house would be too heavy to be supported by the wine cellar ceiling. That gives you an idea how massive a real traditional mass heater here needs to be (1 ton of soapstone is a lightweight).

Side note: our house is made of stone. Lousy insulation. But itself is a mass that can be heated. In fact, after about a month of "charging" the walls** we have enough stored heat we do not need to do over night burns. It never gets much below 70°F over night inside, even when the temps dip to 20°F here.

Hope this helps.

** The house is bone chilling cold if we leave it unheated for a month, no matter how much we heat when we return... such building must be "lived in" to be comfortable --- not a holiday house.

 

[moresnow]

A real mass heater uses a fast, hot burn (unlike a wood stove). So she does a hot fast burn. But the stove mass is too small to heat the house for very long. So has to another fast hot burn. Repeat.

Mass heaters require a lot of mass to absorb a lot of heat, which is slowly release over time. Our house did not come with a mass heater ... actually that was unusual here as most house have them, and my wife really wanted one (she is Hungarian, and grew up with these types of stoves). So we asked around, contacted static engineers and mass stove masons, and they all said the same thing... because our house living area actually sat above our rather large wine cellar, the mass heater needed to heat our house would be too heavy to be supported by the wine cellar ceiling. That gives you an idea how massive a real traditional mass heater here needs to be (1 ton of soapstone is a lightweight).

Side note: our house is made of stone. Lousy insulation. But itself is a mass that can be heated. In fact, after about a month of "charging" the walls** we have enough stored heat we do not need to do over night burns. It never gets much below 70°F over night inside, even when the temps dip to 20°F here.

Hope this helps.

** The house is bone chilling cold if we leave it unheated for a month, no matter how much we heat when we return... such building must be "lived in" to be comfortable --- not a holiday house.

Now what we really want to see is the cellar

Do you have photo's of any common local mass heaters?

 

[St. Coemgen]

Now what we really want to see is the cellar

I only have renovation photos.... Such as the ones below. As I was huge into documenting our renovation. Have not taken much sine then.

Do you have photo's of any common local mass heaters?

I took a lot of photos, but I can not find them. Darn.

In Hungarian they are called "csempe kályha". Any search engine should give a lot of photos. They really are lovely stoves. For example:

 

[SpaceBus]

I only have renovation photos.... Such as the ones below. As I was huge into documenting our renovation. Have not taken much sine then.

View attachment 270715

View attachment 270716



I took a lot of photos, but I can not find them. Darn.

In Hungarian they are called "csempe kályha". Any search engine should give a lot of photos. They really are lovely stoves. For example:

Beautiful, but that would take a lot of loading. Probably more than my tiny Morso!

 

[begreen]

7kw is less than the smallest UL/EPA listed stoves in the US, that I know of anyway. Maybe a small mass heater would work well in a tiny house to have a long time between loading and not overheat the space?

This is matter of perspective. In the land of McMansions, yes it is small. But in Europe some call a 7kw stove large. For example:

Large wood burning stove | HETA Scan-Line 1000 | Robust wood burning stove

The Scan-Line 1000 can take wood up to 50 centimeters. HETA Scan-Line 1000 is sturdy without being clumsy and is built in heavy steel and cast iron.

heta.dk

 

[SpaceBus]

This is matter of perspective. In the land of McMansions, yes it is small. But in Europe some call a 7kw stove large. For example:

Large wood burning stove | HETA Scan-Line 1000 | Robust wood burning stove

The Scan-Line 1000 can take wood up to 50 centimeters. HETA Scan-Line 1000 is sturdy without being clumsy and is built in heavy steel and cast iron.

heta.dk

Indeed, I've been saying all along that most American homes are simply larger than most European homes. Our little saltbox is more like a European house than an American, not only in size but also layout. My family was stationed overseas when I was a kid so I got to experience Italian apartment living, but out in a farming town. A local family owned a "large" single family home and it was pretty incredible really. It might have been 2200 sqft, but the space was used very well and an artisan built the house. I don't think our apartment at the time was even 800 sqft. When we moved to the UK we stayed in a subdivision like in the beginning of Harry potter, it was called Stukeley Meadows. The house was small, perhaps 1,000 sqft, maybe less, but more than enough for our small family. European homes seem generally better insulated and more energy efficient as well. I can see where the 7kw masonry stove would be enough for a 800 sqft super insulated house, but I also understand why they aren't popular in the US.

 

[St. Coemgen]

Beautiful, but that would take a lot of loading. Probably more than my tiny Morso!

Yes, they require a lot of loading. But you only need to load them, and touch off the fire, once in 24 hours (or for larger ones, once in 48 hours)

 

[DennisCA]

In Finland the Porin-matti heater was popular as a hybrid between a pönttöuuni (masonry heater of finnish design) and an iron wood burning heater. Between 200-350kg depending on model, they give rapid heating and stored heat for a while in their mass. A trade off between concepts.

Apparently they are still made in updated versions, but it seems to be only a smaller model:

A pönttöuuni is probably better, but you won't get rapid heating from it, but overall high efficency. A pönttöuuni is a traditional finnish masonry heater. Based on the swedish tile ovens, but the tiles are replaced with sheet metal. It's a superior material, never leaks, never cracks (tile ovens can crack and leak if fired too hard, a pönttöuuni won't). They can weigh up to two tons or more but the average weight is around 1300 kg.

Modern version with glass doors

Dual stoves with copper skins

Schematic from 1940s showing they where quite modern designs even then, note channel for secondary air so you can achieve a cleaner burn. Also note the core stands free from the outside, this reduces internal stresses over the classic tile ovens, which crack easier becaue it's all one piece.

Here's an interior shot of one bein built:

Edit: Link with examples of stoves, with height and mass values to give an example of the range. Also shows some porin-matti stoves.

Murare Ismo Salminen

Also another thing that used to be common in a finnish home was a heating wall in the kitchen. Basically the kitchen would have a cast iron wood stove, behind it was the heating wall, a brick wall with channels for the flue gasses to pass through before leaving for the chimney. This worked on the same principle thus as these heaters. A cast iron wod stove could burn very effectively & clean with secondary air incorporated in stoves from the 1930s onwards, but a lot of the heat was still lost in the flue gasses. Thus the heating wall was traditionally built behind the stove, built into the wall itself. In summer time the wall could be bypassed with a flue-gate so you did not make the kitchen too hot in summer.