new to forum, have some questions

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chewy

Member
Nov 7, 2009
188
Indiana
Hello all

This is my first post and, I want to say hey. I’m sure you here this a lot, but i stumbled across this site after my dad bought an outdoor wood boiler. I had been looking at them for a while and was most likely going to get one. Then my dad came to me and told me that he wanted to purchase a wood boiler to dry down corn in his grain bins during harvest. We purchased a 1 year old free heat machine hybrid fire 150. We’ve been running it for four days, hooked up to a radiator that is placed in front of the drying fan at the bin. A typical full load will last 4 to 5 hours. Is this going to be typical load time once I set it up to heat my 2000 sq ft house and 1800 sq ft shop? It’s an old farm house that is poorly insulated and has 10 ft ceilings. The shop has average to good insulation. Also, is it wise to place the unit 100 ft from the house and a 150 ft from the shop? Does anyone have any installation advice for someone on a budget?

I forgot to add that we are burning unseasoned freshly cut wood that is a variety of types.

Thanks
Erin Patton
 
...we are burning unseasoned freshly cut wood that is a variety of types.

Camp fire works best for this and is a whole lot cheaper. Seriously, no wood burning boiler will perform well with green wood. Your better bet is to cut, split and stack wood now to burn winter of 2010-11 or 2011-12, save up your money, continue to do research to plan your system according to sound principles, and then buy and install a quality wood boiler, hopefully a gasification type, and have economical and satisfying heat over the long run.
 
ty for the reply jebatty

its kinda to late to look into a gasification system. the system that dad is using now was purchased for me to use in my home and shop once he is done with it here in a few days. so basically the system is free to me accept for buying the pipe, insulation, one more pump, fittings, heat exchangers, etc. ok so not free, but im going to do my best with what i got.

i guess i should get used to cutting wood!!!!!!!!!!!!!!
 
chewy said:
Hello all

This is my first post and, I want to say hey. I’m sure you here this a lot, but i stumbled across this site after my dad bought an outdoor wood boiler. I had been looking at them for a while and was most likely going to get one. Then my dad came to me and told me that he wanted to purchase a wood boiler to dry down corn in his grain bins during harvest. We purchased a 1 year old free heat machine hybrid fire 150. We’ve been running it for four days, hooked up to a radiator that is placed in front of the drying fan at the bin. A typical full load will last 4 to 5 hours. Is this going to be typical load time once I set it up to heat my 2000 sq ft house and 1800 sq ft shop? It’s an old farm house that is poorly insulated and has 10 ft ceilings. The shop has average to good insulation. Also, is it wise to place the unit 100 ft from the house and a 150 ft from the shop? Does anyone have any installation advice for someone on a budget?

I forgot to add that we are burning unseasoned freshly cut wood that is a variety of types.

Thanks
Erin Patton


Welcome to the forum,
I don't know what your heat load will be but it sounds like your trying to get allot of btu's out of the boiler trying to dry down corn. Add a house to the heat load along with the green wood and your might be able to do it but your really going to go through the wood. The problems your going to run into is that with the green, wood the wood first has to be dried in the firebox to get it to put out allot of heat...this in turn takes allot of btu's that you lose to drying rather than putting it in the water. Look around the forum for advise on your plumbing scheme you will need. I realize your on a budget but the piping under the ground is not someplace to try and save allot of money on...I've been there and it really sucks knowing that 1/3 of your heat is going into the ground.
 
Jebatty is correct and right on the money. Ill second the hope that you go the gasifier route. I have a neighbor with new OWB. Smokes a ton and he is still cutting and moving wood for this winter. So far Im guessing he's got most of his back yard full of firewood. Not to mention whatever happens with the proposed OWB regs in New York State and how that will effect his operation and entire setup.
 
lawandorder said:
Jebatty is correct and right on the money. Ill second the hope that you go the gasifier route. I have a neighbor with new OWB. Smokes a ton and he is still cutting and moving wood for this winter. So far Im guessing he's got most of his back yard full of firewood. Not to mention whatever happens with the proposed OWB regs in New York State and how that will effect his operation and entire setup.

Not to mention the people on the other recent thread on this forum that are burning ATV tires, aerosol cans and gods knows what else...I hate to see the govt continually passing new laws to restrict individual freedoms, but sometimes people do such stupid things there is almost no choice. Like anything else, a small minority of folks give a bad name to the whole indistry (wood burning) and then laws get passed that restrict everyone. [/end of rant]
 
If you are only getting 4-5 hours burn time I think your draft must be running all the time to keep up with the heat demand and you are losing BTU's to the green wood.
For your house make sure that you are sizing the boiler right, most people undersize them and aren't satisfied with them. Also size your pex accordingly.
What is the rating on your OWB that you will be using?

Gary
 
ty for posting sdrobetson

my setup will not include the bins here in a couple weeks. this is a one time deal that dad wanted to try. we are not even keeping the water at 150 on average and the blower is on non stop. it will only be set up to only service my house and shop. we are already seeing the down fall of burning wet wood, as it is doing what you said.

i still need to do some more research on the underground pipe.

erin
 
hey gary thanks for posting

you hit it right on the money the fan almost never shuts off. im not sure what size of pex to use, it is set up for 1". the boiler is rated at 6000 sq. ft.


erin
 
1in lines might do you if you run seperate one to the house and shop but 1in will only move 80,000btus. Make sure you do the lines right. My suggestion is this:
Use double 1in o-2 lines. 300ft-$220 on e-bay
Have the lines foamed in place in the ditch by a foam contractor. CLOSED CELL FOAM runs $5-8 a ft.
By doing it this way you will besure and have enough volume and will have the best insulated pipe you can get for the least money. Then if you aren't happy with the owb and deside to go with a gasifier your lines will be done either way. Running the lines is one of the most expensive items so you want to get it right the first time. There is a lot of people here that have redone there lines after trying to cheap out and buy the owb dealers fancy new superduper insulated pipe where the insulation melts, gets wet, triple wrapped foil-bubble-foil, dead air space, 1/2 in foam and such. I know I've changed my underground 4 times over the last 25 years and now I finally got it right for very little more than the other times. There are several posts on how to foam in the ditch here but if you need more info pm me and I'll try and help
leaddog
 
ty for the reply leaddog

i will definatly be looking into the closed cell foam installation.

erin
 
Moisture content in the corn running high down there too? There's a ton of it standing in the fields here yet with the farmers in an absolute quandry about what to do with it. MC is running 35%+ to off the scale and the stuff is standing there in the fields getting moldy because it froze before it got fully mature. It's a mess............

I have to say that if you start out burning green wood this year it will probably sour you on wood burning forever. Think of it this way.....say you have a 10 pound piece of wood with 40+ moisture content. That means you have 4 pounds of water that has to be evaporated before any usable heat is emitted by the combustion process. Here's the rub.....10# of dry wood has about 10,500 btu's m/l and it takes roughly 1000 btu's to evaporate 1# of water. So 4000 btu's of usable heat from that piece of wood is being used for the purpose of evaporating the water in the wood. You've basically just shot yourself in the foot efficiency wise because 40% of the heat content just went up the chimney in the form of water vapor.

Looking at it another way......let's assume that you use the unseasoned wood in a typical outdoor wood burner that runs about 40% efficient itself (real world number not factory hype)

A: Starting with 100% of the heat stored in the wood or 10,500 btu's deduct the 4000 wasted by evaporating the moisture and you have 6000 btu's available for heat transfer to the water. An average efficiency number for any OWB is about 35-40% so multiplying that 6000 btu's remaining by 40% leaves you with 2,400 btu's available to heat your house. That equates to a LOT of wood burned over the course of the winter.

B: Now if you start with seasoned wood, say 20% moisture content, you'll have about 8,000 btu's in the firebox. If you burn it in a modern design gasifying boiler your combustion efficiency is an honest 80% which leaves you with 6,400 btus instead of 2,400 in the first scenario.

Can you envision hauling cutting splitting stacking and loading 3 times as much wood in scenario A vs scenario B? Not saying you should look a gift horse in the mouth and turn down the OWB your dad is giving you ...........just trying to prepare you for what you're getting yourself into. And yes..........I'd probably run a pair of 1" lines to each location or else a single 1-1/4" pex like Leaddog says.
 
heaterman ty for posting

yes, corn is wet out of the field, 23 to 26% no signs of mold so far, thank god. we are running into a spot where we had to break down and run one of the lp burners on the fan.

i understand the fuel loss when burning wet wood, but i have an endless supply of wood. we have also been in the process of cleaning fence rows so we already have trees cut down. what about dead trees? would these be better fuel for this year?

erin
 
chewy said:
heaterman ty for posting

yes, corn is wet out of the field, 23 to 26% no signs of mold so far, thank god. we are running into a spot where we had to break down and run one of the lp burners on the fan.

i understand the fuel loss when burning wet wood, but i have an endless supply of wood. we have also been in the process of cleaning fence rows so we already have trees cut down. what about dead trees? would these be better fuel for this year?

erin

If you have standing dead wood, get it cut, split stacked and covered up if you can. It will be some better than green stuff.
 
heaterman said:
chewy said:
heaterman ty for posting

yes, corn is wet out of the field, 23 to 26% no signs of mold so far, thank god. we are running into a spot where we had to break down and run one of the lp burners on the fan.

i understand the fuel loss when burning wet wood, but i have an endless supply of wood. we have also been in the process of cleaning fence rows so we already have trees cut down. what about dead trees? would these be better fuel for this year?

erin

If you have standing dead wood, get it cut, split stacked and covered up if you can. It will be some better than green stuff.

Than try to find time to c/s/s and cover, 2 or 3 yrs wood ahead. I'm guessing trying to find the time will be the hardest part. But you'll burn less wood, even though you have a endless supply.
 
I would guess "150" stands for 150,000 btu. To move 150K btu you will need to run at 15-20 gallons per minute. That will require 1.5 inch pipe. You could run two 1" pipes, but keep in mind a single 1.5 inch is worth about three 1 inch pipes in terms of how much water it will carry. Also, consider that your water temps may be above 200F at times with a boiler running at full tilt. This is a bit high for pex tubing. I am doing steel pipe for my main boiler loop. Of course, as an open system, you then have to deal with oxygen damaging your pipes (though it's not that big a deal.) Do it once, do it right. Put in a line big enough to carry your heat load.

I agree completely you would be happier with a gassifier. I would work with what you have now but make sure you are ready to put in a gassifer when this boiler burns out.

Andrew
 
hey Andrew

do you mean one 1.5" line for both runs, or 1.5" lines for both? the boiler i have has inch fittings so is it a big deal to go up in size? what about the heat exchanger? the ones ive seen have inch ports. would it handle the volume? the pump that i have is an 1/8 taco pump set up for inch lines, is this a problem?

man im starting to get comfused!!!!!!!!!!!!

erin

p.s. man, the colts really slid by today.
 
emesine said:
Also, consider that your water temps may be above 200F at times with a boiler running at full tilt. This is a bit high for pex tubing.

Andrew

If his aquastat is set properly he should never see those temps,especially running an older house and a shop on 150k. I run mine at 185 in the middle of winter and will adjust in down as it warms up some.

Gary
 
Your best bet is to try to keep your runs as short as possible - i.e. draw a line between the house and shop, and put the boiler on that line somewhere. You can't serve both with shorter lines, obviously, and if the boiler is on the short length, what you gain on one side, you lose on the other... I would go with either 2 x 1" runs for each loop, i.e. 8 pipes total, or 1 x 1.25" or 1.5" runs for 4 pipes total. (2 loops, each with a supply and return) Because of the way PEX is priced, it will probably cost about the same either way for the pipe, and it will also run about the same for the foam, as the number of pipes in the trench really doesn't change the amount of foam needed... Use "02 barrier" type PEX, so that you will be able to use the same pipe with a gasifier later.

While it is best if you can get pumps and HX's that are set up for the larger pipes, just having the restrictions in a few places will be better than having restrictions all over the entire system... As others have pointed out, the underground piping will be one of your biggest expenses, and doing it cheap now won't save a lot, and will cost you to redo it again right later... If you do a search through the forum, you will see that one of the biggest single complaints w/ OWB's and other remote boiler installs is inadequate heating because of undersized pipes. We are trying to keep you from making the mistakes that many others have...

Gooserider
 
hey Gooserider, ty for posting

yah, im glad to get all the advice i can get. you guys are being a great deal of help. if i do a storage tank down the road, lets say next fall, would i need the extra volume of water?

erin
 
chewy said:
hey Gooserider, ty for posting

yah, im glad to get all the advice i can get. you guys are being a great deal of help. if i do a storage tank down the road, lets say next fall, would i need the extra volume of water?

erin

Not quite sure what you mean by "extra volume of water" but storage will help with the efficiency in most cases - even with an OWB. However depending on where the storage is located, you might even need the ability to move more water. The idea with storage is to run the boiler at full blast, using whatever heat is needed for the loads, but dumping all the excess into the storage - then when the boiler runs out, heating from the storage until it cools down and you refire the boiler for another cycle... This means that you need to have plumbing that can readily handle moving the full output of the boiler to your storage tank.

I would put the storage in one of your buildings (and pump from it to the other one) just on the general idea that having the storage inside will let you take advantage of whatever heat it loses.

Gooserider
 
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