"WEIGHING" my options

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Armaton

Member
Aug 22, 2011
147
Hastings, Michigan
Hi guys,

Been reading this forum for months gleaning insights on as many gasification boilers as I can. Trying to wade through the avalanche of info, to determine which would be my best choice. I have a newer (2008) 1800 sf ranch, fully finished walkout basement. Heat loss calc from Smokeless heat says approx 50kBTU loss (if I did it correctly). Forced air for main floor, and in floor radiant in basement. My plan is to have boiler and 1000 gallons of storage in an outbuilding, and use heat exhanger for furnace plenum, a plate exchanger for the infloor, (utilizing a "Hydroshark" modulating electric micro boiler now), and a sidearm for my DHW. after talking to Reps for 5 of the boilers I'm looking at, I figure any of the smaller boilers will work. In fact most of the reps said their smallest boiler would do the job, (only the rep for the EKO suggested going larger, ie 60, and let it idle if need be). I was leaning towards a Vedolux, however while looking at the specs I noticed quite a disparity in the weights from the Vedolux's and everything else. The Vedo 30/37 are 639/650 lbs and the next lightest boiler in the group is the Empyre Elite 100 at 945 lbs, everything else is over 1000 lbs. Wondering about longevity if the materials are that much lighter, will it last? Opinions? Ooops accdentally posted in "Wood shed" hopefully a moderator will change to "Boiler Room"
 
I have never thought of the weight of a boiler as an argument for one over another but I do think that you have a good point. Personally I have compared the weight for other purchases, usually farm tractors or heavy equip. and all other "measurements" being equal, I have gone with the heavier (more steel) choice.
With wood boilers I think that alot of the weight might be in the refractory items of the unit and may not be a reasonable item to judge by. How about just comparing the thickness and materials of the firebox and water jacket? That would prolly be a better guage than just the weight of the whole boiler. Good luck!
 
I am also going through the decision process, hopefully this will be the last winter with my current unit. And, I have also come to a point where a Varmebarronen is my first choice - to date, at least.

There is another thread on here, somewhere, with the same discussion - is the lighter weight of a Varm a concern? From memory, I think it was a no - I'll have to see if I can find it.

EDIT: This place has a great searcher.

Found this:

https://www.hearth.com/econtent/index.php/forums/viewthread/64466/

Not sure it's the same one I was remembering or not...
 
Welcome! I guess my first question would be "where is all that extra weight"? My guess would be its primarily in the plate used and perhaps also how much refractory they contain. If the exterior dimensions are roughly the same and one boiler weighed 30+% less I'd certainly think twice and ask a lot of questions.

FWIW I think your heat loss of 50k sounds a bit high for a newer home at 1800 feet.
 
FWIW I think your heat loss of 50k sounds a bit high for a newer home at 1800 feet.

Our home was built in 1956, about 40' x 40', added insulation and new windows equaling about 60' of wall space. Based on wattage of baseboard heaters, which heated the house originally, now backup to our wood stove, our btuh supply is about 35,000. That's also the rating of our wood stove, and the stove heats the house just fine to -35F and lower. We don't heat the basement with the stove, but have extra electric (4000w = 13,600 btuh) which we only use intermittently to keep the basement at 50F. Total electric heating bill/year is about $200.00.
 
I agree that the 50,000 btuh sounds a bit high for your home. If it's 35k or 50k, you will have to have thermal storage to make a wood boiler work reasonably well for you. A 100k BTU boiler with 400-600 gallons would work great. Strongly recommend you ignore/dismiss anyone who suggested a 60kW boiler for this application.

Not sure what is going on with the weight of the VB.....my guess is that the steel is the same thickness since it would have to meet the same euro-standards as most of the other boilers you are looking at.....on the other hand, I can't believe the difference is solely down to refractory weight. I'll be interested to see how this develops.

Good luck, and keep us posted. Chris
 
ewdudley said:
maple1 said:
see if I can find it.

EDIT: This place has a great searcher.

Found this:

https://www.hearth.com/econtent/index.php/forums/viewthread/64466/

Not sure it's the same one I was remembering or not...

Or this one?

https://www.hearth.com/econtent/index.php/forums/viewthread/52943/P15/#590621

Actually google is a far better searcher, you can restrict it to which site you want, with exact phrasing, logical cunjuctives, and so forth.

That's the one I was thinking about.

Quite interested to hear more input from Varm owners - especially the natural draft models. The 40 is on the top of my short list.
 
Thanks for the replies and links. I too thought the loss calc was a bit high. I may have counted my basement twice, what with them asking for walls, and perimeter of cement. Entire basement is studded with at least R 13 blown in wet cellulose on the cement walls, and R-19 in the walk out wall. However couldn't talk my wife out of 9' ceilings upstairs so that adds some, actually heating just short of 3600 sf total. Haven't been able to find anything in the literature on the thickness of the plate used in the Varms, but I agree that if it passed the Euro standards it must be fine. I also don't see the refractory (that is supposed to last 10 years per the link Eliot kindly supplied) weighing that much less than the other stoves that the reps tell me should last 5-7. Maybe I'm just too pessimistic. I always seem to look at stuff that I want to buy and imagine the worst case scenario. Like a full firebox with a power outage, if I have a heavier stove with proper overheat protection or a lighter stove with the same protection, I am of the opinion that the heavier built model would/could withstand it better. Of course if I have battery backup won't be a problem either. Don't get me wrong, the Varm is still at the top of my list, but was hoping for some insight from users.

Brandon
 
Installed and configured correctly, I think any of the major units would work. I have a Paxo and like it, no complaints really. The Garn strikes my fancy but I already have the Paxo. If you are making a dedicated building you may find a small Garn is simpler to install and operate rather than a boiler and storage. I like having my storage in the basement and the boiler in an outbuilding. There is no wasted heat from storage, it all tempers the basement which tempers the radiant of the first floor.
 
I can try to weigh in, but I guess as of right now Im an owner, not a user, since my Varm isnt hooked up yet.....

I read the same thread on the weight issue, but for me it was an asset to have it lighter so I could get it into my basement. I still buggered it up and dented it, which makes me sad.

As far as the refractory, the Varm (I have the Vedolux 37, I cant speak to the natural draft models) has refractory brick for the bottom of the firebox and the nozzle. This then discharges into a steel combustion tunnel that moves the flame/heat towards the front of the unit, and then it goes to the back up the Hx tubes. I dont believe that there is any refractory material at the bottom of the boiler, and most of the others that I looked at had additional brick/cement/refractory there as well. That could be the reason for the weight difference. Honestly I dont know, but I wanted to provide some input.

Also, I would think that if its lighter, that means that more of the heat would go into the water (where you want it) instead of to the mass of the boiler thats heating up (maybe not where you want it). Sort of like the newer low mass cold start boilers, you dont need to keep all of the metal hot all the time like with the old cast iron beasts.

I can get some pics of the interior of the firebox / flame chamber if that helps at all, but again its not the natural draft model, which might be different.
 
I wanted to share the information I compiled before purchasing my effecta lambda 35.

Many of the European boilers (including the EKO40 I used to have) contain refractory cement in the very bottom of the secondary burn chamber where as the effecta lambda has a fully water jacketed steel bottom in the secondary chamber (obviously steel is much lighter than thick refractory cement). In addition, the useful high temp. BTU's generated in the secodnary chamber travels much easier through the steel into the water than than thick ceramics into the water.

Many European boilers also have a ceramic "half pipe" or "after burner" where as the effecta has a stainless steel afterburner (once again steel is much lighter than ceramic-in addition, the stainless gets red hot much quicker than a large mass of ceramic-in addition, it does not crack aftter reapeated hot/cold cycles).

Most European and doemestic gasifiers use refractory cement in the primary and secondary doors where as the effecta uses a thick piece of much lighter and heat resistant vermiculite.

Lastly, many boilers on the market use 6 or 7 mm thick boiler plate steel where as effecta uses 5 mm thick steel (once again, the thicker steel makes it harder for heat to transfer through and into the water).

I performed a large amout of research before purcahsing my effecta (including the fact that they have been around since 1983 and have a very robust, proven boiler design).

Thus, when comparing the weight of different boilers it is very important to know just where the extra weight is/what its being used for.

Brian
 
Hey folks,

I meant to post a few days ago but I forgot.

Like Clarkbug, I also have a yet to be installed Vedolux 37. So no experience in operation yet.

I made a point over the last couple of years to see several gassers in operation and I am sure I would have been happy with any I looked at.(Garn, EKO, Biomass, Tarm)

The Varmebaronen just felt right to me. Very high quality construction IMO and really well designed.
Some convenience features I like are:
Supply and return fittings on both sides of the boiler.
Flue pipe adapter that swivels and has flue temp probe and easy clean out access.
And my favorite part, the HX tubes. Easy access to remove turbulators and clean as needed.

As far as the weight "issue", I had similar concerns as some of you all but I felt in the end that quality of materials and construction were more significant than the thickness of the material. Time will tell.
Its worth noting that the Vedolux is a very compact unit compared to other boilers in a similar Btu range. Physically about a third smaller in fact. It holds about 30 gallons in the water jacket and the firebox is only 3.6 cu ft. They also shaved some pounds with the doors as these are cast aluminum.

I hope this info is in some way helpful to you folks comparing boilers.
Noah
 
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