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Walltherm Zebru Gasification Fireplace experiences.

Post in 'The Boiler Room - Wood Boilers and Furnaces' started by scooby074, Sep 30, 2012.

  1. scooby074

    scooby074 Feeling the Heat

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    I searched the forums for any mention of this company and debated between fireplaces and wood boilers on where to put this, hopefully this is the right place.

    Does anyone have any experience with the Walltherm Zebru gasification FIREPLACES? http://www.wallnoefer.it/cgi/sdcgi....action=&fname=&ebene=005&mkrecno=14&iklasse=1 I saw one today for the first time and am VERY impressed. It's something i"m considering for my next house as a retrofit in my current place would not be cost effective. Hopefully this is within 5 years, so Im doing some very basic planning now.I intend on having infloor heat and incorporating other energy saving techniques like thermal storage and passive solar, maybe even adding a PV or wind system generation system. My already too high power bill can only go up, so planing ways of saving money on my next place is a prudent idea.

    The unit is a gasification fireplace which to me is the best of both worlds (fireplace and boiler).I was unaware a product like this even existed until today. When I thought "gasification boiler" i pictured a large, ugly, likely gray unit plugging away locked in the basement or outside, not something like this:

    [​IMG]

    This company also markets solar collectors and can integrate them into a whole house system as well.

    Now this unit isnt huge, only 51000 BTU if I remember right, but the fellow I talked to says he heats his house with one (he also has their solar collectors) and only burns 1.5 cord/ year, heating a house approximately the same size as mine, 1700 sqft. I burn almost 8 cord. The savings in wood alone would go a long way to pay for the unit, let alone the savings in labour.

    Cost IIRC was around $6500 for the stove, $800 for the circ pump and i cant remember how much the storage tank was, but overall not too bad. Plus there are some significant rebates from the government to the tune of $3500 on a complete system (I think).

    So, bearing in mind that im at the VERY preliminary stages of planning my next place, are the Walltherm units a good investment?

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  2. Frozen Canuck

    Frozen Canuck Minister of Fire

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    AFA investment goes your probably the best one to pencil that out. Yes cheaper than many boiler setups for sure. I remember these units from a previous thread. IIRC the only downside mentioned was having to deal with the ash in your living area much like a stove. To be honest these IMO make alot of sense in a newer home that is not a drafty old..........nice appearance, benefit of dhw, the possibility to use this for radiant heating as well. Cant hurt to sit down & run the numbers for your situation. In a well insulated home this is all one would likely need. & yes they look great without breaking the bank.
  3. maple1

    maple1 Minister of Fire

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    Depends on the situation. It would also require that all the wood being burned, and all the dirt from cleaning & maintenance, passes through the room it is in. If it fit my space & plans, I'd consider it definitely.
  4. velvetfoot

    velvetfoot Minister of Fire

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    Did you look at the length of wood it takes? I recall it being very short, from what I read, but they might have other models.
    I don't recall a thread on it.
  5. willyswagon

    willyswagon Burning Hunk

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    I looked at them very hard for about a year. I just didn't feel in the end that I could make my old house tight enough to make it work. I could never get it to the point that 51000 btu would cut it.

    I'm assuming you are dealing with the rep out of Cape Breton.
    If so keep in mind that his house is supper effeicent, and he has a large solar system( i think he said $12,000), with a 1000 gal storage tank that was around $3500.
    His system works well do to the stratification that can be achieved in the storage system.

    It is a great looking unit, and from some of the reviews i've read from Europe, it seems to work well.

    It just didn't fit my needs, and like most newer products to Canada, you won't find many people with any experience operating it.

    PS It has a very small fire bax
  6. velvetfoot

    velvetfoot Minister of Fire

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    I can see how you could use the wood stove aspect to heat the downstairs and use the hydronic heat for upstairs and domestic hot water.
  7. scooby074

    scooby074 Feeling the Heat

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    Thanks for the comments guys.

    Yes it was the guy from CB, Nice guy, Seemed pretty passionate about alt energy and his product.

    I agree, 51000 seems small. In my current place I have an undersized stove.. I'm NEVER making that mistake again ;). However the the little bit of information I can find on the product seems to indicate that it punches above its weight... One thread I read was about a guy in Ireland, in an old, drafty farmhouse that heated it fine with this unit. I couldn't find a single mention of the Walltherms here on Hearth. If anyone knows of such a thread, Id be interested.
  8. goosegunner

    goosegunner Minister of Fire

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    I would find out how many lbs of wood the firebox will hold. That would give you an idea of how often it would need attention.

    Are you thinking that this would burn continuously or start a few fires a day and burn until out?


    gg
  9. scooby074

    scooby074 Feeling the Heat

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    I dont know how it would work for burns. I think most people load it up and burn allowing the thremal storage tank to store all the heat from the fire and release it though the day, then refire and repeat the procedure at night.

    As to capacity, the firebox holds 25 kg of 13" wood which is supposed to give a burn time of 5 hrs.

    Here is about the only video I could find for the unit in English. It describes the operation of the unit.

  10. willyswagon

    willyswagon Burning Hunk

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  11. scooby074

    scooby074 Feeling the Heat

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    Thanks for the links, especially the first. Neither thread came up when I searched.

    I see you installed the Empyre, how do you like it? The North American style gasification units are significantly different than the Euros in capacity! The Empyre is what 125000 BTU and can take a 24" stick. I bet you could put the Walltherm inside it :)
  12. willyswagon

    willyswagon Burning Hunk

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    Time will tell what it is like in my place. I have talked to a couple of people that have the Empyre and they are happy with them. The long sticks sure make it easy and fast for blocking the wood.

    It has only been in for a week, and the weather has been to warm to run it.
  13. BoilerMan

    BoilerMan Minister of Fire

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    13" wood? Ouch. I think it's a cool idea, as you'd have plenty of radiant heat from the glass alone.

    Pros: Nice to see the fire, and know when to add more wood, fire in living room

    Cons: Fire in living room, ash cleanup, 13" wood in living room etc.

    TS
  14. willyswagon

    willyswagon Burning Hunk

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    One thing to remember is that you would need to have a battery back up to run the circ pump if you had a fire going and the power went out.

    The boiler only holds 16 litres ( 4.25 USG) of water. This could lead to it over heating very quickly in a power failure as there is not much water there to absorb the heat, possibly causing it to blow of in your living area:confused:
  15. BoilerMan

    BoilerMan Minister of Fire

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    Man, than is not much water...... and the 13" wood thing....... Someone have some splainen to do.

    TS
  16. scooby074

    scooby074 Feeling the Heat

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    Yeah 13" wood doesnt sound that great does it. Seems like lots of extra cutting and waste in the form of sawdust.
  17. scooby074

    scooby074 Feeling the Heat

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    Good point on the circ pump. I hadn't thought of that. Coming home to blow off in the living room would suck
  18. PassionForFire&Water

    PassionForFire&Water Minister of Fire

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    Like a lot of stuff from Europe this indoor gasifier comes in a small but powerfull package.
    The wood length needs to be max 12 - 13.5" for optimum burn.
    The advantage of smaller/shorter wood is that you can cut back on years of drying.
    A maximum of 18% Moisture content is crucial, but this is the same for any gasifier I would say.
    It burns pine very well. This is the wood availalble in the area where this unit is manufactured.
    The unit comes with a standard cupro-nickel cooling loop that handles the potential overheating. Unit comes with a Watts ST30, hooked up to the city water or well system.
    The safety valve needs to be discharged to a safe location. This is typicaly not the living room.
    We recommend a 120 gallon water storage tank.
    Heat distribution of the unit: 36,000 BTU/hr to the water, 15,000 BTU/hr radiant heat into the room.
    LK820 is standard availalble or pumpgroup PAW K36E is optional, this to prevent condensation.
    3/4" piping will do.
    You can use a DC pump of a battery charged by a solar panel. The pressure drop over the heat exchanger is minimal.
    6" double wall chimney.
    The unit sells very well in Germany, Austria, Switserland, Northern Italy and Japan.
    The unit sells good in Canada.
    The US will catch up, ... eventually.
    More questions, more answers.
  19. BoilerMan

    BoilerMan Minister of Fire

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    I do understand that the 13" wood will dry much faster due to the greater endgrain exposure, however...... Has anyone ever tried stacking 12-13" wood? If it doesn't fall over your better than me. I usually have about 1/4 cord of ends, uglies, etc that are in that length range and they are hard to stack to any height.

    TS
  20. PassionForFire&Water

    PassionForFire&Water Minister of Fire

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    I have seen them in a double row, butted against each other, for 3 or 4 layers and then 1 row perpendicular. 5/6 feet high
  21. scooby074

    scooby074 Feeling the Heat

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    Thanks for the information Passion. I take it that your a retailer for Walltherm?

    the local rep I talked to recommended the PAW circ pump. He said it was more money, but it had the hot water bypass to improve the life of the boiler. (Sorry, im still not up to speed on boiler technology and why some are better than others)
  22. PassionForFire&Water

    PassionForFire&Water Minister of Fire

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    I'm the importer/distributor for the USA.
    The PAW K36E pumpgroup is just a more elegant solution to a boiler return water temperature protection valve (like an LK820).
    All is included in the package: circulator, bypass, valve .... and price.
    The reason why Roland is recomedning this, is because the manufacturer recommends it in europe. But the PAW K36E pumpgroup it is significant less money in Europe.
    The PAW is faster in bringing in bringing the boiler water up to temperature but not significantly faster to justify the money.
    Key is that you have some sort of boiler return water temperature protection in your system setup to avoid condensation.
  23. PassionForFire&Water

    PassionForFire&Water Minister of Fire

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    Soem pictures of the safety cooling loop and PAW pump group.

    Attached Files:

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