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rreidnauer
01-08-2006, 07:03 PM
So I was to the Pennsylvania Farm Show this weekend, and I was looking at some interesting things like saw mills and alternate heating devices, some of which were wood-fired boilers and furnaces. The ones that really got my attention were the multi-fuel models, particularly the oil/wood boilers. I knew of the outdoor style wood boilers, but little about them. At the show I had the opportunity to do some comparisons. There are two that I like. One is the Mahoning Outdoor Furnaces wood/oil boiler, and the other is Benjamin Heating Products indoor wood/oil boiler.

The smallest Mahoning was like $5000, but was jacketed in stainless steel and had a HUGE firebox with a huge loading door too. It also had a massive ash pan and door. This is a serious boiler, and probably WAY more than I need.

The Benjamin I wasn't able to get a price on, but "should be" quite a bit less. It takes up much less space, has a closed loop domestic hot water coil, though a much smaller firebox, but it isn't grated. From what I've been told, non grated is good because when loading a grated version with more wood, you would knock most your ash, and the fire along with it, into the ash pan. At the same time, I see a negative of having to stop the wood burn the clean out once in a while.

The key factor I was contemplating was the oil burner, and if it could be run on WVO. You already have the advantage of the boiler to preheat the oil, so . . . . .

Has anyone ever attempted to feed WVO to a Beckett burner before? Can it be done?

I'll tell ya, this would be a slick setup if you could. Heat your home and get your hot water with a practically free fuel source.

Info links to these furnaces:
http://www.benjaminheating.com/cc500_series.htm
http://www.mahoningoutdoorfurnaces.com/morinf.htm

gregorama
01-09-2006, 04:53 PM
I saw this at the Seattle Home Show last year, several sizes were available. I would burn anything! Had gas/propane/electric backup, and a large water mass to absorb fast fires. Pretty cool - you go first!

http://www.beselfreliant.com/heating/index.cfm

Greg

rreidnauer
01-10-2006, 06:54 AM
Thats an impressive unit, but I bet it's pricey too. I'm wondering what amount of wood (or whatever fuel) is required to heat and maintain that much water.

That Benjamin CC500 unit is starting to become really appealing the more I read about it. (not that finding information about it on the net has been easy) Even though the firebox is smallish, and it's only 40 gallons of water, so if it's well insulated, I'd guess that it wouldn't take as much heat to maintain temperature, compared to a large unit of say 200-300 gallons, with much larger surface areas of water jacket. Also, a big outdoor unit will have to deal with an additional 40 degree average winter temperature differential, compare to an indoor unit. At the same time I have to consider shock temperatures of a small capacity unit, verses a large capacity unit which have the ability to absorb the cold return water when calling for heat. Currenty though, I'm in a house with an oil boiler of similar small size, and it works exceptionally well. If real log homes are as efficient as Skips, would I even need to have a monster unit capable of heating the house, pool, hot tub, garage, walkways, driveway, etc, etc, etc? I don't want to have to be stoking an entire tree just so I can have manly amount of heat for the entire neighborhood. I only need to heat my 35x35 log home, and supply my hot water, so the little Benjamin has drawn my desire. The price (which I still haven't received) will be a determining factor though. It seems all too often these "alternative" units cost way more than they should, simply because the dealer is just trying to bilk every dollar they can out of the consumer looking to find a new way to lower cost heating. :evil:

Cheam
01-10-2006, 04:59 PM
If the company wants too much for a woodburning stove and you want to use wvo anyway why not put a conventional oil furnace and run it off wvo. just make sure that you can get your hands on the amount of oil that you will need

rreidnauer
01-10-2006, 05:10 PM
Yup Cheam, getting that much WVO was one of the concerns I had with a fully dedicated setup. That's why this dual fuel boiler has my attention.

I got to get an old used burner assembly and start experimenting. I have a feeling a lot of it comes down to the right nozzle and air band setting. (oh yea . . . . and warmed, thinned oil)

rreidnauer
01-10-2006, 07:04 PM
Dag gum it all!!!! :evil: I finally found a website willing to tell me what a Benjamin sells for, and naturally, it's just as I feared. The MSRP for it is . . . . . ya ready for it . . . . . $8000!!!!! :shock: What the heck?!?! I can get a similar sized conventional oil or gas boiler for $1000. It's just like I said earlier that they will bilk you for whatever they can get. :evil: :evil: :evil: I was thinking, "OK, I'd be willing to go 2500, maybe 3000 tops." Ha, jokes on me.

Dang it. OK. I got some rethinking to do.

Cheam
01-10-2006, 10:59 PM
man that is steep, I was looking at a high efficiency gas furnace this month and they wanted 6500 for it. with prices like that I am leaning towards having a conventional wood stove in my living room, especially with firewood cutting permits running about $2.00 a pickup load.

ChrisAndWendy
01-11-2006, 03:05 AM
Can the multi-fuel units use waste motor oil? Now that would really be neat. Most service stations are paying for the removal of the oil as do resturants for their wvo. Chris.

rreidnauer
01-11-2006, 08:53 AM
I wired a waste motor oil burning, hot-air heater for a garage once. It wasn't the prettiest thing. Simply hung from the ceiling, typical of a small commercial/industrial heater. It wasn't very clean either. A quick web search shows there are boilers available too. I also know Mahoning (mentioned at the beginning of this thread) makes a waste oil boiler, though, I don't know if that meant motor oil or cooking oil.

I also just found out that Mahoning makes one size smaller than what I thought was their smallest, so I'm looking into prices for that. (and if it's dual fuel) I'd just like to have a dual fuel boiler for any and all circumstances.

gregorama
01-11-2006, 08:32 PM
$6500 for a gas furnace? RUN AWAY! I learned this trick from an elevator conversation with a HVAC salesman. I went down to the local Carrier warehouse, asked for their "scratch and dent" section, and they had about 15 units there for about $4-500. I said "hmmm.. is this all you have?" and he scratched his chin, said "I have a whole truckload of last year's units, was gonna send em back for credit, but you can have one for $500." Brand new, 80%, sure, but $500 bucks! :!: Put it in myself; it fit right in where my old furnace sat, with only minimal tin work. It has 2 speeds, runs at low about 90% of the time. I had to get a contractor friend to actually do the paperwork, but I paid him, he paid them, and I picked it up.

One thing I found: in my 1977 tract home, the contractor put in an 80,000 BTU furnace. I did the heat calculations (on the web), and came up with 28KBtu, worst case. Seems they would just buy a bunch of big ones (about the same upfront cost, but more to operate), and install them; no complaints about underheated houses! My unit has 40K on high, and works great. DO THE MATH!

Speaking of math, I priced the TurboBurn unit at 8-9000. Although your fuel can be free, that's a fair chunk up front. They (and the Home Show guy) claim just one hot fire, set and forget, in a day, dead of winter. The shed or room you build has about 2' of insulation, 3 tons of water to absorb all that heat. The physics look pretty good. Maybe they have a "scratch and dent" section! :idea:

Greg

farmercolby
01-11-2006, 09:05 PM
I have a heatmor outdoor wood furnace that I paid 3500$ for in 2001. for a thousand more I could have had the waste oil burner in it. Its made out of stainless steel. The fire box, flue, and door is all water jacketed. The door is water jacketed to pull as much heat from the fire as well as to prevent warping. I wouldn't trade it for anything and the company was honest and easy to work with.

I have burned wood, railroad ties, power poles, tires, weeds, waste oil, and more. If you manage your furnace right you can burn all that stuff without much smoke or stink.

sparky
01-12-2006, 07:02 AM
Hey Greg
Great score on the gas furnace :!: Knowing who to ask and the right question to ask sure can make a difference. Don't forget to ask one simple follow up question, "Is that the best you can do?" You'll be amazed at how often that their first price isn't the best they can do. :)

Now do tell,...... where did you find the web site to do heat calculations?
Thanks for sharing.
By the the way love your picture, but is that really your best side? :lol:

rreidnauer
01-16-2006, 01:01 PM
I just found another boiler of great interest. Though it is wood fired only, it's design is slick. It is loaded with refractory firebox and insulation, uses a downdraft flue, and water tube heat exchanger.

The way it works is it burns the fire up to 2000 degrees and heat soaks the firebox and large, unsplit logs you dump into it. They claim the downdraft/heat exchanger brings the temperature down to 300 degrees by the time the gasses depart the boiler into the smokepipe. Now here's the neat part. Once the unit reaches it's high setpoint, it closes off all air to the firebox, completely extiguishing the fire due to lack of oxygen. The unit then "coasts" on the stored heat until getting down to the low setpoint of (I'm guessing) 1500 degrees, opens the dampers, and the introduction of oxygen at that temperature causes the wood to reignite on it's own, since the temperature is well above the flash point of wood.

Really neat if it works, and sounds like a great wood saver. They claim a 24 YEAR warrantee too, but haven't looked real close at the details of that. Price? $5000 for the smallest 120,000 BTU unit.

I'll have to look further into this one.

http://www.rohor.com/

gregorama
01-16-2006, 09:38 PM
Sparky: I believe I used www.heatload.com but I also I saw this one, not sure if it's good or easy (you've gotta be one or the other, ya know...) :twisted: An almanac or the Weather Service site will have your local degree-day information.

http://www.ccithermal.com/Products/HeatLossCalculation.html

Also go to the Department of Energy site, look for a program called "ResCheck". It takes all your "envelope" information (windows, doors, wall thickness - I used 1.25 R/inch for log) , tells you if you're within code.

And yes, his first offer was 600, if I recall.. :)

Greg

sparky
01-17-2006, 07:17 AM
Greg,
The first web site you listed is not coming up because it has a comma at the end. :wink: No worries, I just wanted to clear up any confusion it may be causing. It's a site worth looking at. :) Thanks

eesnard
01-29-2006, 12:33 PM
I don't have any firsthand experience with Central Boiler but I have read good things from users


http://www.centralboiler.com/dualfuel.html

ponyboy
01-29-2006, 01:24 PM
Found a few more links.

http://www.newhorizoncorp.com/

http://www.profab.org/

Fred
03-24-2006, 08:39 AM
I've read some very negative reviews of those large outdoor wood furnaces


For instance

http//www.woodheat.org/technology/outrickperth.htm

Your mileage may vary, etc...

i'm sure some of the problems can be remediated with good engineering, but seems risky.

This technology (Wood gasification) seems more intelligent.

http//www.woodboilers.com/default.asp
http//www.newhorizoncorp.com/
http//www.charmaster.com/prod.html

chadfortman
03-24-2006, 03:35 PM
I read the article and yes its got it fact but take them for who they come from. The way i to look at it if you can build a log home i shure you can take care of a boiler unit.
If we didnt want save money why would wet be building are own homes.
And thats what the boiler unit does.
Sounds like a lazy lib wrote the article :evil:
I getting one and i have a back up wood stove to.
I am for them and saving on cost of gas ore electric buy corn, wood, and pellets ore used oil they all work in them.
I done allot resurch on them and have some the paper work heatmore.com one them.
Evere one got there thoughts and ideas dosent make any one correct in any area.
I gone for one burn everthing my idea hahahah
No atacks just my ideas
Peace out
:D