Evaluating new wood/oil boiler systems

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fint

New Member
Jul 16, 2008
6
Capitol Region, NY
We are sold on the purchase of a brand new oil boiler that also burns wood, indoors. (wood is practically free for us, and our current oil boiler runs approximately 55% efficient.)

We are unsure of which products will give us the best bang for our buck. We're limiting the expenditure to about $9,000 for our 2,000 sq ft home. Every sales person has the best product, in their eyes.

We are currently evaluating Tarm, Benjamin CC500 (Maine Wood Furnaces), and have thrown out Greenwood from our pile of propaganda.

Any suggestions from happy or otherwise customers?
 
I am not sure, but I think there is a difference in efficiency between multi-fuel boilers and just wood. You may be better off to put in a straight wood gasifier and keep your old oil boiler simply as backup. You may find that you don't use it much at all. Here is a link to a gasifier comparison table I have started on my website: http://woodnotoil.googlepages.com/gassifiers However, it does not include the oil/wood combos. I think Nofossil has an eko gasifier and a tankless propane now as backup. That may be an option if you want to abandon the ineffecient old boiler. I am sure others have more experience with muli-fuel systems.
 
I would agree that putting in a wood-only boiler and using your existing oil boiler for backup is probably the best approach. My main reason for saying that is that if your combination boiler ever springs a leak or becomes otherwise crippled, then you have no backup. If you have unlimited free wood, then I doubt you'll be using the oil boiler at all, especially if you eventually add hot water storage.

Welcome to the Boiler Room, btw.

If you're committed to getting a combination, I think Tarm makes the best one.
 
If you are going to go Multi------I would stay with Tarm only......if you are going to do with two boilers, you have other choices. As you may be able to tell by scanning through the forum, some of us are partial to the more efficient tarm/eko/econoburn downdraft-type fan-forced boilers...due to high efficiency. However, some folks are on a tighter budget, so other units are often considered. In any case, such a system should be considered a long-term purchase.....and budgeted in that way.
 
We tend to go away in the winter for 2-4 days at a time. Last winter, our old boiler shut itself off a few times and we came home to almost frozen pipes and my poor dead fish. Keeping the old boiler as a backup is not an option, we have evaluated it when we were thinking about getting an outdoor wood boiler.

Thanks for the Tarm recommendation, but why is it the best?
 
In multi, Tarm is the best because of many reasons - one is many decades of full production of these designs. Another is the high quality of Danish goods in general. The Tarm uses two separate combustion chambers and two large heat exchangers for max efficiency. If you compare the heat exchange area (combined) of tarm to any other multi-fuel you will see a difference.

So mostly it's a matter of engineering and experience.
 
Speaking of heat exchanger size ... that is one spec hard to come by on these units but looking at the water volumes is it fair to say the tarm has a larger exchanger and the EKO and Econoburn are similar in size. If so is this where part of the price difference comes from?
 
A few other observations regarding the choices available.

Ideally, the two independent system approach is best. However, keeping the old boiler (which is apparently shot) and adding a wood furnace requires an additional flue, which will probably add $1500 - $2000 to the install cost, and would likely push you over your $9,000 budget. Since the old boiler needs to be replaced as well, it seems a new oil boiler plus the wood boiler would be necessary to get the system you want, which will definitely push you way over budget. In this situation then, the dual-fuel makes more sense, since it saves both the new chimney cost and the replacement oil boiler cost.

A major problem though, is I thought Tarm was already sold out for the year? The un-availability of many boilers this year was a major factor in my decision to jump on an EKO 60, paying for it in June. We just got delivery and put it into the basement last weekend, and I figure it will take me well into August to get it hooked up. If the Tarms are not available this year, it makes the decision somewhat moot, at least for this heating season?
 
boilerman - Always remember the option of power venting to solve additional flue problems. If the oil boiler works at all, it could remain the backup for a few years putting off the cost of a new one.

Just to note, I think the Woodgun actually has the largest water capacity out of the boilers around the 200,000btu range. If storage will be added at some point, these water capacities matter little. Go for the best price and/or the best support in your area. You have to live with these decisions for a long time, so it is worth some extra cost to do it right.
 
boilerman said:
We just got delivery and put it into the basement last weekend, and I figure it will take me well into August to get it hooked up. If the Tarms are not available this year, it makes the decision somewhat moot, at least for this heating season?

Heating season extends into April in these parts!

Even a boiler hooked up by the end of Jan. will see some good use......

Not sure if Tarm is sold out........maybe someone knows better than I (I know nothing on this subject).
 
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