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Hoss OWB and Other Questions

Post in 'The Boiler Room - Wood Boilers and Furnaces' started by TNBob, Jul 6, 2013.

  1. TNBob

    TNBob New Member

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    I've been reading about gassers / OWBs for some time now and found this forum, and the contributor's years of experience, to be the best source of info on the web on this topic. So, I'm posing a few questions hoping for some advice.

    We have a small home (just under 1,000 sq ft) with no room for an in-door furnace so we are looking exclusively at outside models. We are also anticipating heating our future greenhouse with this same boiler/furnace.

    1. I live in the Upper Cumberland area of TN and am currently looking at a TN produced unit (http://tennesseeoutdoorfurnace.com/he-models/). I haven't found any posts on this forum about these Hoss units so I thought I'd see if anyone cared to share their experience with this brand or their thoughts on the units and their specs.

    2. We've always thought of wood-based heat as part of our long-term, off-grid goals. We see it as risk management and future hyper-cost avoidance. However, as near as I can tell all these OWB units require some continuous supply of electricity and water to operate. Are there any standard or ball-park numbers we can use to calculate power and water consumption for the system?

    3. Our home currently uses propane heaters and does not have any HVAC ducts. Therefore, I've been leaning towards installing a hydronic radiant floor system but I have heard from several people lately that I would be better off installing a heat exchanger and ducts -- they claim it's less expensive to install and provides a more comfortable living space. Are there long-term users of either approach here that can help me sort this out?

    4. We've done a good job of insulating and sealing our small home. As a result we do have a humidity problem during the winter. I haven't seen anyone here discussing dehumidification with these types of systems. Do most of you run separate dehumidifiers to control humidity?

    Thanks in advance for any input.
    Bob

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  2. StihlHead

    StihlHead Guest

    Well, I seem to be one of only a few pro-OWB people on this site. Many OWB bashers out there. When I was with my ex, we had a similar situation as you but a larger house (about 2500 sq ft). No room to put the boiler inside, and we already had an electric hydronic floor heating system in the house (very expensive to run). Even in that situation, the smallest OWB that Central Boiler (CB) made was the best option for us. We bought and installed a CB classic system, and retrofitted it into the existing system with flat plate heat exchangers (one on the floor loop, and one on the hot water heater). The thing worked great from the start, and the ex is still using it now about 8 years later. The only real drawback is that they eat a lot of wood, but she has over 100 acres of trees, so that was and is not an issue. We burned on average about 8 cords a year, and the boiler paid for itself after only 4 years of use (as compared to electric bills) and we were far warmer and more comfortable.

    High humidity was not a problem there, so I cannot answer your questions about that. However, I would advise that you go with a hydronic floor heating loop if possible. That is by far THE BEST heating I have ever lived with in any house, with all kinds of heating from NG to wood to coal to electric to heating oil. Radiant heat is the best heat of all, and in my view beats the pants off of any forced air ducted heating available. I would also advise that you only buy a EPA approved OWB at this point. It is only a matter of time before more states outlaw non-certified stoves and boilers of all types. Oregon did not have any such laws when we installed our OWB, but they have recently passed laws requiring that any house sold has to have EPA or state DEQ approved wood burning appliances, including all wood stoves, boilers and OWBs. Washington state has outlawed all OWBs, period. New England and the mid Atlantic states have outlawed all but EPA approved OWBs. Many regions and counties and cities have also outlawed OWBs, or require EPA ones be installed. Another thing about boilers is that you want to buy one from a company that has been around for a LONG time. There are only a few out there that have been in business over 20 years, whereas new boiler companies pop up all the time. I have seen so many come and go I cannot count them all.

    I have never heard of Hoss, so I cannot say if they are good or bad or otherwise. However I have been following the OWB industry and issues for about 10 years now. I have never heard of Hoss and they do not have EPA approved boilers, so I would avoid them. I would stick with Central Boiler, The Wood Dr, Hardy, Heatmor, or any of the long term boiler makers that have EPA Phase 2 approved OWBs. My personal experience with CB has been very good, and hence I can highly recommend them. Here is a list of phase 2 EPA certified boiler models from the EPA:

    http://www.epa.gov/burnwise/owhhlist.html

    As an aside, I would also only go with an open non-pressurized boiler loop. Many arguments for and against that, but I have installed enough plumbing systems and I have seen the damage that pressure systems can do. The only real advantage I have seen with a pressurized system is less cavitation in the circulation pumps. I would also only go with plain steel models. SS is brittle and tends to crack, and is very difficult to repair/weld. It also costs a lot more, and has lower heat transfer properties. Go with good thick plain steel and you will be better off.
    hobbyheater likes this.
  3. StihlHead

    StihlHead Guest

    Oh, and one other thing. Go with the smallest boiler system that you can find. With a house as small as yours is, you do not need anything larger than the smallest CB model available, like the classic 4030 which are about $5,000. That is a non-EPA model if you decide to go that route. The smallest EPA model from CB is the E-classic 1400 which runs about $8,500, but that would allow you to run a second line to heat a greenhouse or garage, or whatever else you want. They come pre-plumbed with 2 sets of tapped intake/outlets to allow for 2 separate lines (simply plumb and run 2 separate Taco pumps).

    And no, I do not work for CB or get anything from them for recommending them. I have owned them, installed them, run them for years and dealt with their engineering staff as well as several sales people. All good and knowledgeable in my experience.
  4. hobbyheater

    hobbyheater Minister of Fire

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    Not knowing how your propane heaters are vented ? Propane heat can a source for condensation.
    Make plans for burning dry well seasoned wood , it will burn much cleaner and you will burn less wood for BTU"s delivered .
    Good luck and welcome to "Hearth.Com"!:)
  5. TNBob

    TNBob New Member

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    Thanks for both posts. I've heard great things about CB but I always appreciate hearing from actual users. You have raised several good points I had not thought about with Hoss (i.e., years in business, and EPA certification). Since they offer a gassification model I just assumed they met all EPA standards -- bad assumption.

    We prefer the cleaner burning, more efficient design of the outdoor gasifiers but are concerned that we won't have enough of a load to efficiently operate a gasser until we get the greenhouse built. I'll look into those CB models you mentioned.

    I appreciate your feedback on the hydronic floor heating. Intuitively it makes sense that it would provide a more even steady heat which should mean a more comfortable living space.

    We have about 14 acres of hardwoods so I'm expecting to have a lifetime supply of good hardwood for the winters in this area.

    Thanks again.
  6. TNBob

    TNBob New Member

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    Allan, both the propane heaters are ventless and we discovered late last winter that they were indeed part of our problem. I am researching small pole barn designs to build a covered area large enough to contain 3 years worth of wood. Based on what I've learned in this forum, dried, aged wood produces maximum burn efficiency.

    Thanks for the input and welcome. It's a great community here!
  7. jebatty

    jebatty Minister of Fire

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    What thought have you given to a small wood stove in the house? Besides the gassification boiler and storage in the shop, we very nicely heat our 1500 sq ft house with a wood stove and our climate is much colder than yours and we have a long winter. Take care of the greenhouse decision when that time comes.
    711mhw and BoilerMan like this.
  8. TNBob

    TNBob New Member

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    Jim -
    There's a lot we like about a wood stove in the house but the space configuration is such that we can't easily keep the grand kids safe since the only spots we can put a wood stove are in the high traffic areas of the house. So, at the moment a small indoor wood stove is our fall-back option.

    Thanks.
    Bob
  9. jebatty

    jebatty Minister of Fire

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    I understand the issue with grandchildren and high traffic areas. We now have six grandchildren, from 3 mos to nearly 11 years, and all of them have grown up on visits to our house with the wood stove. All of our grandchildren understood what "hot" meant, we bring them close enough to the stove to feel the heat to reinforce the danger, and fortunately we have had no problems so far. It can be done, there is a risk, and you need to find your comfort level with your children on this.
  10. StihlHead

    StihlHead Guest

    There are several great benefits to having an OWB. With OWB radiant floor heat I never missed the stove or a fire. Actually we had an EPA fireplace insert, but it sucked for heating (literally, it sucked the heat right out of the house) and we used it rarely (mainly when the electricity went out). The biggest benefit of the OWB is that there is no extremely hot fire source in the house. No stove or fireplace to burn your house down with. Also no hot stove to burn yourself or anyone else on inside the house. Also no need to drag firewood, bark, dust and bugs into the house. Also one less smoking appliance inside the house, and far less smoke inside the house in my experience. Also no need for small splits; you can burn much larger cut wood and rounds in an OWB. Also no need for putting a giant hole in your ceiling and roof, no need for a hearth, and no appliance to trip over inside the house. My living room would be a lot larger w/o the stove and hearth here, and if I had the money, I would not hesitate to put in an OWB and hydronic floor loop here. Well, one can dream. You can adjust the heat zones to heat and cool the house variably to your tastes. I like my bedroom a bot cooler for sleeping in.

    BTW: As for safety, the CB we had had a faulty controller at first, and it boiled over several times. It got hot, boiled over, and the steam took all the heat energy away and that was it. No burned down house, or even any damage to the OWB. One of several advantages of an open pressure system. CB replaced the controller, and gave us more corrosion resistant water additive under warranty. My chemistry buddies tested the CB corrosion formula and said it was the best they had seen or tested. It works well. The water loop in the boiler needs to be replaced every 3 years, but that's about the only long term maintenance you need. I designed our boiler loop so that the high point could be bled for air. It was plumbed with one inch pex, one blue and one red colored to ID the lines. The boiler is 6' from the house which is the only restriction (fire code) in Oregon for accessory structures. I put it on a concrete slab but that was not required (though I think it was better).

    If you get and heat a greenhouse, heat the soil and not the air in there. The Russians have been doing that for years and have better results with it that heating the air. Again, radiant heat is best. ;)
  11. Tennman

    Tennman Minister of Fire

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    Bob, Mostly agree with all said. I actually checked the coefficient of thermal conductivity of regular steel vs stainless and was surprised to learn the regular steel transfers heat at a rate almost 3 times better than stainless..... huh. The rate using SS is still probably way more than adequate for the job so probably not relevant. I wouldn't take for granted the time required to collect, split, stack, store, and dry your wood. I can't first hand compare the increase in efficiency of a gasser vs the standard OWB, but there are many posters here over the years that have transitioned from OWBs to gassers and they are always stunned by the increased efficiency which directly correlates to reduced time handling the chainsaw, splitter, moving and stacking, etc. We're ready for our 5th season and if the time required to prepare my wood doubled for a season... well. But your situation is very different from our larger far less efficient home. We burn about 5-6 chords here in southern Tennessee. But, the time savings over 10-15 years will still be very significant of a gasser vs OWB. We had no choice and had to use our existing duct work. The universal opinion here is that radiant is more uniform and more efficient for our wood boilers being able to continue to work at much lower water temps. Not having ductwork already I'd say that decision is easy for you. If you KNOW your load will increase in the future... greenhouse, more rooms, etc, well get a boiler large enough for your long term needs. I've run our BioMass gasification boiler for 4 years and am just now adding storage. Like most of us, eventually you'll see the advantage of being able to store heat away for later use which means, within reason, if you oversize your boiler and you eventually add storage, you'll get your storage tanks up to temp quicker, i.e. no disadvantage of having too big a boiler. I'm not looking forward to winter, but have finally gotten the wood and our system to the point that we have excess energy to put somewhere... so looking forward to running with storage (not winter). You've found the right place and group of wood burners. If you've committed to a OWB, there are LOTS of happy Hardy users in the hills around our property and some of those have been burning for a long time. I see the smoke often. I was planning on installing a Hardy to get us free of enormous propane bills, but found this forum and am very thankful for the education about gassers. For a smaller home maybe the difference of processing time of a OWB vs gasser will not be a big deal, but there are a host of other advantages of using a gasser other than just the wood processing time. We're located outside Fayetteville, TN and have had a number of folks come see our gasser since this type of system is like hen's teeth in the South. Lots of very knowledgeable and helpful folks here. Take your time and study here which will dramatically increase the probability you'll be happy living with your system. Because you will be "living" with it, unlike just adjusting a thermometer. Best wishes.
  12. StihlHead

    StihlHead Guest

    Any OWB with a EPA certification will likely be a modified gassifier these days. Looking the their web site, Hardy only makes an indoor type gasifier now. Wood Dr. has flipped to all pressurized outdoor wood boilers. Heatmor only makes SS boilers now. So it seems that the only long term OWB company left with a low pressure, mild steel, outdoor EPA-II certified unit is Central Boiler.
  13. Tennman

    Tennman Minister of Fire

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    How about that Stihl... Hardy is now doing gasification. I didn't know about that until this moment. Hardy products are rarely discussed here but very popular in the South. As far as OWBs go all the folks I talk to around me that use them are very happy and the boilers last a long time. But none of the local folks have ever heard of gasification boilers down here. FWIW, all Hardy OWBs look like their new KB165 gasifier. They're just shiny stainless cubes just like the new version sitting somewhere near the house or out near a small barn with the wood. Hardy doesn't mess with sloping little roofs. Just flat stainless top. So it looks like the KB165 is an outdoor or indoor gasification boiler. Looks like they got the EPA Phase 2 back in 2011. Have fun Bob. Looks like you have options.
  14. StihlHead

    StihlHead Guest

    They all pretty much have to go with gassers to get EPA certified. Cleaner burning, more efficient. New England/New York lobby pressure to get EPA certified OWBs, and more states are requiring OWBs to be EPA certified.
  15. NCFord

    NCFord Member

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    Am I the only one who has installed a HOSS? I installed one last winter for a customer, I believe it was the 300 model, the smallest one they make. It is way to big for your 1000sf house. I think it is 300,000 btu's. I don't know what size greenhouse you are talking but that's a lot. The unit I put in is heating 3500 sf plus 1000 sf workshop. I'm sure you want to deal locally, but this stove uses a ton of firewood. I think they may advertise that they have a gasification boiler but I don't think they do. My customer who bought the boiler thought it was a gasser but it is clearly not.(I was not involved in the purchase process) I will go to their website and see if they have a new model out. If it were me I would look a different boiler and true gasser just save on wood and all the time that goes into cutting and splitting etc.
  16. TNBob

    TNBob New Member

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    StihlHead - Thanks for all that great input. I'm sold on hydronic radiant floor heating. Did you setup a separate zone for each room of the house? Would I need to build a mechanical room to house all the connections or can all of plumbing be done in the crawl space? I was thinking that if the physical plumbing connections don't need a lot of servicing I would mount them in the crawl space but if I need regular access to the hydronic system I'd have to add a mechanical room to the outside of the house just for the zone connections, controllers, etc.

    I've read a bit about heating the soil in the greenhouse rather than the air and was planning on researching it some more. Have you seen anything that talked about sizing the heat source for a greenhouse that heated the soil vs. the air (ie: a thermal load calculator for using the heat-the-soil approach)?

    Appreciate the input on the different units on the market. We've been very impressed with what we've heard from many of the CB customers. Glad hear they took care of your issues. Great service is just as important as a great product.

    Bob
  17. TNBob

    TNBob New Member

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    Tennman, thanks for the TN region input. Had not even heard of Hardy but glad to find out about them and will do some more research on them. Any thoughts on how they compare with CB? The KB165 looks interesting but I wasn't able to find a price for it online. I'll contact the folks in MS and see what I can learn.

    I'm guessing you have more humidity in your part of TN than we do up here on the Upper Cumberland Plateau. Do you run a dehumidifier during the winter to manage moisture? After developing mold problems last winter my wife wants to make sure we do everything we can to manage humidity in the new heater system design.

    We are open to OWB units but prefer the efficiency of gassers. I enjoy working outside but would rather burn the wood with maximum efficiency so I have more time for other projects. I was hoping for 4 chords of wood per winter, or less. The challenge is that the gassers cost so much more than the OWBs. While the extra wood the OWBs burn isn't truly free its cost is small in expenses but significant in time and physical energy.

    All the research and learning is a lot of fun but we really wanted to get our system worked out and installed this summer because we assumed that Fall/Winter was the busiest time for the furnace industry. We figured we'd get our best deals by buying during their slow season. Starting to feel like I'm running out of time.
  18. TNBob

    TNBob New Member

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    NCFord -- seems like you are the only experienced HOSS person on the forum. Appreciate your input. They were suggesting I could use their 400,000 btu HOSS 400HE and still operate it within their design parameters just heating our 900 sq ft house. I think they said that it would work ok because of the 400 gallons of water their unit holds. From what I can gather, their HE units only differ from their OWB units in the flue design. I can accept that the altered flue design makes it more efficient but I don't see how that makes it a gasser.

    Since you installed the HOSS for a customer, I'm guessing it was in the central NC region. Do you have any recommendations on gassers that have done well for your customers here in the SE US? What do you recommend to your clients for humidity control when they install a radiant floor system?

    Appreciate your input.
    Bob
  19. StihlHead

    StihlHead Guest

    We had a solar hot water heater tank and a regular water heater, as well as the hydronic heating loop stuff all in a large closet off the laundry room/pantry in that house. I retrofitted that with the boiler loop PEX and the 2 heat exchangers with a tempering/mixing valve on the main floor loop. I forget what I set the tempering valve to, but we had hardwood floors and tile, so the temp was set pretty low. I would recommend a separate small room for the hydronic heating loop as well as the headers, tanks and floor loop heat exchanger that you can get to easily to adjust the floor loop mixing valve, floor loop zone adjusting valves, and find/fix leaks and access the bypass valves. You will need to add/continue the boiler loop line to the DHW wherever that is in your house. I did not plumb the electric boiler hydronic floor loop, but it had 10 zones set up off a header with valves on each loop. They ran all over the house in 1/4" or 3/8" PEX lines. The hydronic header was connected to 3/4" copper which is more or less the same as 1" PEX (PEX is measured at the outside diameter, and copper is measured from the inside diameter).

    I do not have any information on greenhouse soil/radiant heating demand, as I have only used electric heating mats in my greenhouses. I do not know what the load would be. I used two separate methods for sizing the boiler for the house. One was using the volume of the house and area low temperatures, and doubling that value. The other was using the previous electric rates to determine the BTU requirements, and they came out about the same. The smallest CB unit was more than enough for that. In use, even at 10 deg. F. the boiler kept the house nice and warm (though it ate 2x the wood as it did when it was 30 deg. F.). I would imagine that the smaller EPA rated CB boiler would be more than enough for your small house as well as a moderate size greenhouse. I would use a tempering/mixing valve off of a Hx in the greenhouse on a hydronic loop and keep the loop about 50-60 degrees? I used and recommend the Honeywell hydronic tempering/mixing valves. You will get radiant heat in the greenhouse, and so the air temp can get pretty low but the plants will still remain warm. The demand would vary on your needs, if you want to keep them from freezing, or if you want to have a tropical zone in the dead of winter.
  20. NCFord

    NCFord Member

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    Bob,

    Unfortunately, I am not a professional installer, I have only installed a couple of OWB's and they have all been forced air. Everything around here is forced air because of the need for AC in the summer. It makes for a very simple install, with the simple addition of a water to air heat exchanger in the ductwork. I have not installed any gassers, though I am in the process of installing my own econoburn 100. I think 4 cords of wood per winter is very achievable for you size house, perhaps even less with the right size boiler. Good luck
  21. Tennman

    Tennman Minister of Fire

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    TNBob, there's a discussion going on right now titled BioMass, Nexgen or EKO which you should read if you already haven't. I don't know anything about the Hardy Gaser, but I can speak for the BioMass that it is designed to incorporate most of the features of the high end boilers discussed here, but it's made in Poland (eastern Europe if it makes you feel better). You can read my logic expressed in that thread where the original poster is making the same decisions you are at the moment. I can't speak about Central Boilers other than the fact that they are not discussed much here by the usual group of wood boiler gurus. That's usually a bad sign... But again I have NO first hand knowledge of their products. But absence of a boiler's discussion in this site is a warning sign. Others hopefully will chip in. I recommend you build a simple spreadsheet of the top manufacturers you're considering and narrow it down, like most of us here did. As far as top line gaser boilers here, I'd say there are 3 tiers based on price; good, lower priced foreign made (EKO, BioMass, Attack), and awesome top end (Garn, Froling, Tarm), then many others in between. As you read here manufacturers names will start popping up a bunch... Hardy very infrequently and lots of folks ASKING about Central products.... They must have an awesome marketing effort. But again, I know nothing about their products other than people come here, ask about them, and often choose something else after some reading..... for whatever reason. Enjoy. But I can speak about customer satisfaction on Hardy products and although I see them smoking, the owners around me in the hills love them. Their new gasser has to be better. Keep reading. Cheers. Oh and BTW, parts for EKOs and BioMasses are well stocked and readily available.
  22. StihlHead

    StihlHead Guest

    If you want the real deal about boilers, gassers, OWBs and EPA requirements, I would advise you look on other web forums and avoid this one (look at MEN, AS, or any one of the OWB forums). This site is way too biased toward wood stoves and very biased against OWBs, and CB in particular (they are the biggest producer, and thus are targeted). I would also avoid any boiler made outside of the US and anything that is not EPA approved in the latest anti-wood burning (especially anti-OWB) political climate.
  23. TNBob

    TNBob New Member

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    Thanks Tennman. I'll go find that discussion and read through it. I have seen the Garn, Tarm, EKO, and Attack names in other threads I've read. For the most part, the ones I had read about in the other threads were much more expensive than our budget. You make some good points about CB. The Hardy folks will be at a home show in Knoxville in a few weeks so I'll hopefully get some great info directly from their staff at the show.
  24. TNBob

    TNBob New Member

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    Thanks to your input, and others here, we've made "EPA approved" part of our 'must-have' criteria. I prefer to buy 'made in USA' products whenever possible. Don't believe I've ever run across MEN or AS and will try to find them.
  25. TNBob

    TNBob New Member

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    Really appreciate that input, it helps me a lot with the layout for our system. Your suggestions on the greenhouse and soil temps makes me think I could setup a "subtropical" zone for citrus, etc. on a warmer loop and then a temperate zone for the other plants on the "50-60 degree" loop. Thanks

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