I'm looking at forced air outdoor furnaces.

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amateur cutter

Minister of Fire
Hearth Supporter
Aug 20, 2010
1,170
West Michigan
Hi all, don't get over here much, so be kind, I may not know what I want.
I have a 150,000 btu indoor furnace in my shop which does a good job, but it's old & indoors. It heats 1600 sq feet of shop which isn't the best insulated + 3 overhead doors. Then 800 sq feet of house/apt. that's well insulated. I'm looking at the Shaver thermowind. Give me feedback please. A C
 
In general I think the outdoor furnaces are the least desireable kind of wood heating appliance in terms of bang-for-your buck and efficiency. That thermowind is not cheap and the price on their website does not include any duct work.

Keep in mind that here in west MI you will very likely need to have an outdoor wood burner quite a distance away from your house if you plan to meet code with it. This will add an astronimical amount of cost if you plan to use burried duct work if I had to guess.

What kind of existing heating system do you have in the house? If it's forced air heat I'd suggest a boiler would be a much, much better investment. All you need is a coil in your plenum like many of us run. You can read on and on about outdoor vs indoor if you start considering boilers.

And last, if a boiler is 100% out of the question, I'd suggest you look at a low cost pellet unit or even a simple stove for your home. I'd really suggest you avoid the outdoor furnace if you value the time it takes you to collect and process firewood...and if you value your hard earned dollar.
 
I'll second everything stee said. A boiler with a forced air heat exchanger in the house is definitely the way to go. There's no practical way to efficiently move hot air from an outdoor installation into your house. You'll save whatever extra the boiler setup costs in the first year in wood savings alone.
 
Hmmmm, those were my concerns as well. The thermowind would run about 1/2 of what a boiler would.$ 5000.00 complete vs. $ 10,000.00 for a high capacity boiler. Right now, I'm running an old 1970's longwood dual fuel add on unit, on wood only.This thing is 150,000 btu, & keeps up no matter what the weather. It's just not real efficient. The goal is only loading the wood appliance 2 X a day, & getting the unit out of the building. I really like the idea of a boiler to heat dhw as well, I'm just not sure the price is justifiable. What do you guy's recommend for outdoor boilers. I'd need 2 zones & h xchangers. to do it right. A C
 
Hmmmm, those were my concerns as well. The thermowind would run about 1/2 of what a boiler would.$ 5000.00 complete vs. $ 10,000.00 for a high capacity boiler. Right now, I'm running an old 1970's longwood dual fuel add on unit, on wood only.This thing is 150,000 btu, & keeps up no matter what the weather. It's just not real efficient. The goal is only loading the wood appliance 2 X a day, & getting the unit out of the building. I really like the idea of a boiler to heat dhw as well, I'm just not sure the price is justifiable. What do you guy's recommend for outdoor boilers. I'd need 2 zones & h xchangers. to do it right. A C

I think you could get into a boiler for less than $10k. But I also do not think you could have pulled off the furnace for $5k with a sell price of mid $4,500 for the unit itself. You would have a lot more than $500 into ducting in my humble opinion.

You have competing goals. Loading a wood burner, in most cases, twice a day does not lend itself to high efficiency unless it's grossly oversized with thermal storage. In addition, the lowest cost/highest efficiency is typically going to land you with an indoor unit (depending on chimney arrangements).

I do not think you're going to be in the market for a downdraft gasifying boiler. Even though that is what most folks on this board run and recommend in the boiler room. If I were in your shoes with a budget goal of $5,000 I'd look for a quality wood boiler and consider either housing it inside your home or building a shed in your yard to house it. Build it as close to your house as code allows in order to minimize thermopex costs.

http://www.cozyheat.net/FD-42-Cast-Iron-Wood-Coal-Boiler_p_151.html

I bought my setup from Cozy Heat up in Indian River, MI. I'd suggest you give them a call and ask them a million questions. I'm not sure if Dave is still there but if he is, he's very helpful.
 
That's very helpful info stee, thank you. I'm not stuck right @ 5k either. About 7500.00 would be max. I will put the thing as close to the building as possible. Inside is what I'm trying to get away from for space reasons. No basement or corner to put it in. The current furnace is in about as good a spot as it can be, but the ins co doesn't like it because of the automotive repair in here. I'm leaning toward large water capacity due to huge heat loss through the 3 overhead doors that open & close constantly throughout the day. The 150,000 btu unit will keep the temp up fine even in the coldest weather, it's just time consuming to feed the thing so much. I can burn 10-12 cord in a cold winter, which is a lot of wood obviously, but I have an unlimited supply & like to cut. My issue I think is that this old furnace just isn't ever gonna be tight enough no matter what. I don't "need" a gasser here, & I like simple & reliable. I do burn well seasoned wood, so smoke isn't really an issue, & neither are neighbors.

If you get sick of my questions, just say so, I can over think stuff way beyond reason.;hm Around here, everybody just puts in a CB model one size bigger than they need & calls it good. I only wanna do this once, so I'm sure I'm over thinking/researching it. I don't believe anything a manufacturer or salesman claims, so I like to check with people that have been there done that. Everybody around here loves their CBs & the local dealer as well, so that's good. Some of the diy installs I've seen are frightening to say the least.

I've learned that most folks here @ hearth.com are pretty straight up so just let the opinions fly. Thanks Again! A C
 
Just my opinion but with that budget why not look at a used unit, a well cared for & maintained boiler will likely have a few decades left in it. IIRC there have been a few for sale by members in the for sale section of the forum. Worth a look at least. If you find a unit there or elsewhere that fits the bill members will be happy to answer questions on that boiler.
 
Yep an EKO 25 & a 60 are/were for sale the 25 might be small for your situation but it has a lot of "comes with", worth a phone call/email IMO. Also if you are considering a used unit I would suggest that you start a thread in the for sale/ wanted section of the forum. The good folks here can help you with proper sizing for your situation.
 
I think the shaver uses 1/2" steel for the firebox and that translates to poor heat exchange. Not a efficient unit especially when you add the air duct work. Water is a much better way to move the heat IMO.
 
Just my opinion but with that budget why not look at a used unit, a well cared for & maintained boiler will likely have a few decades left in it. IIRC there have been a few for sale by members in the for sale section of the forum. Worth a look at least. If you find a unit there or elsewhere that fits the bill members will be happy to answer questions on that boiler.

Good call, I've looked locally on CL & want ads, but nothing really around. Being an absolute genius, it never occurred to me to look in the for sale section here. DOH! Thanks.
 
Now is definitely the time to tackle this if you want heat this winter. H2Oasis in Rockford is another potential source. But I would also support the used idea. In addition, there are plenty of small manufacturers just north of the Grand Rapids area. I found one on CL this morning selling units in the $3600 range, outdoor, no shed required. I know NOTHING of the quality, performance, etc of these types of boilers. I suspect they will not be particularly efficient but will they be better than what you have now? Possibly. And they would enable you to get the burner outside. I wouldn't buy one of these without talking to numerous current owners (references) and making sure the manufacturer has a decent warranty.
 
Thanks all, & stee esp. I'm doing research now on the owb manufacturer's, rep, warranty, etc. I'll check out the tip on H2 oasis stee. I'm gonna buy quality & durability over initial cost even if I need to wait a little while longer. I can't see regretting the purchase or install in a few years because I didn't do it right, or went cheap. A C
 
Make sure you are keeping in mind that OWB's are probably going to come under EPA scrutiny in the near future. I know some areas are already regulating against the classic smokey OWB which requires new installs to be gasification units of some sort.

As always, it's better to spend the money to do it right the first time rather than wish you would have. I wish I would have gotten an add on furnace with secondary burn now that it's all said and done. With my new garage having in floor heat, any new install for me will be a outdoor gasification unit feeding the garage floor and a water-to-air exchanger in the house.
 
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