OWB wood usage question

[miller1]

My brother-in-law has a woodmaster 5500 and is heating a 1400 sq ft house, 200 ft away from the furnace, he is also heating a 2500 sq ft, old farm house
100 ft away and also a 1000 sq ft storage building @ 50°, he is complaining because he is going through 30+ truck loads of wood a year, i told him that is to be expected with that kind of sq footage, he is also heating water for both houses. I heat a 1500 sq ft house and my water with my 4400 on 10 loads a year, so i figure his usage is pretty normal, what do you think?

 

[Kevin in Ohio]

Not near enough info to make an assement. What needs to be looked at is how much energy was being used in the previous system. The thing people can't seem to grasp that wood, along with ANY other heating option, does NOT make your home more efficient. If you had an energy hog before, guess what, you still have one after and it will take just as many BTU's or in his case more. He's added the hot water and loss in the pipe length. In an uninsulated home that amount would probably be on the low side.

Variables are home size, "truck load" size, construction, insulation, usage, temp held at, water used, installed correcctly with drainage under feed lines and on and on.

 

[leon]

how much wood could a wood chuck-well you know.

My brother-in-law has a woodmaster 5500 and is heating a 1400 sq ft house, 200 ft away from the furnace, he is also heating a 2500 sq ft, old farm house
100 ft away and also a 1000 sq ft storage building @ 50°, he is complaining because he is going through 30+ truck loads of wood a year, i told him that is to be expected with that kind of sq footage, he is also heating water for both houses. I heat a 1500 sq ft house and my water with my 4400 on 10 loads a year, so i figure his usage is pretty normal, what do you think?

His barn and the homes are on three pumps circuits and the water is passing through the boiler three times a fast so it will need more heat of course!

The only way he will gain anything or stay a head is to have thermal storage-meaning either one very large tank farm of hot water-for example the insulated storage tanks in the round or square to store heat for later circulation by the pumps at each location to simplify plumbing.


If he has a 3000 or more gallons of thermal mass for each location-meaning

2 or more 1500 hundred gallon tanks per location to store heat/ hot water to then circulate it from there he will continually heat the closed loop of water in the boiler to heat the water storage tanks using less wood and labor.

The circulating pumps will only draw water from the storage tanks thermal mass and not from the boiler reducing the amount of hot water drawn from the boiler to heat everything.


He will have a balanced heating load with little or no losses of thermal mass as the tanks are insulated anyway and the water can be kept hot year round.



leon

:agree2:

 

[boyland]

I wish i could get away with 30 truck loads year. Heck I go through 50+ truckloads a year heating 4500sq, water, spa, and pool.

Now I agree with what the guy above says but I do not think it is as simple as looking at your old bill and 1 to 1 ratio.

First the OWB is about 50-60% eff at best prob not that good. Gas furnances newer models range from 80-93% eff.

I used to keep parts of my house at 60 now nowwhere is lower than 67.

My house is pretty well insulated but there is a lot a sq ft and is is spread out with a lot of wind hitting walls. I originally calculated the 1 to 1 ratio I expected to use 14-18 cords. I am really going to use 25-30 cords almost 2 times what I originally expected. Now when you cut that much wood you really appreciate how much work that is.

So the number you are stating seems very reasonable and and pretty eff given the sq ft.

 

[Marklambert61]

adding more water

The addition of more water to a system will not in any way improve its efficiency...

Storing heat is a bad idea unless your using some passive system like solar. You are much better off to just produce the BTU's required as needed.


The new high efficiency boilers (If there is such a thing) in fact have very small water capacity.

Mark

 

[Kevin in Ohio]

I wish i could get away with 30 truck loads year. Heck I go through 50+ truckloads a year heating 4500sq, water, spa, and pool.

Now I agree with what the guy above says but I do not think it is as simple as looking at your old bill and 1 to 1 ratio.

First the OWB is about 50-60% eff at best prob not that good. Gas furnances newer models range from 80-93% eff.

I used to keep parts of my house at 60 now nowwhere is lower than 67.

My house is pretty well insulated but there is a lot a sq ft and is is spread out with a lot of wind hitting walls. I originally calculated the 1 to 1 ratio I expected to use 14-18 cords. I am really going to use 25-30 cords almost 2 times what I originally expected. Now when you cut that much wood you really appreciate how much work that is.

So the number you are stating seems very reasonable and and pretty eff given the sq ft.

Didn't mean to imply it would be 1 to 1 on usage. Just that if you use a lot of Oil, propane, electric currently, your going to use a LOT of wood too.

I feel your pain on usage, I had the same thing when I first installed mine. I knew the house was terrible when I moved in and the first year used 28 cord. 1800 sq ft 2 story with full basement and 1800 sq ft fully insulated garage with radiant floor heat.

House had NO insulation whatsoever. Started in the Spring with total strip to the studs and insulated with new windows as well as housewrap. 8 inches in first floor sidewalls and 6 inches on second floor. 14 inches on ceiling. Used 13 cord of mixed dry wood the next year and have been averaging that now for 5 years.

SO many variables as I stated as one guys truckload is NOT another guys. wood quality, climate adds in the mix. I think his tag says Michigan so He's about the same as me temp wise so if his truck loads are normal I think he's doing well but again, need more info to say for sure. A truckload of pine does not equal a truck load of oak, correct? Sorry for the confusion.

 

[mtfallsmikey]

30 "truckloads"...maybe 15 cords?....I've already run thru 6-7 cords, still 2 1/2 mos. to go.

first line of defense...insulation, weatherstripping.

 

[boyland]

yeah defintely many variables. I found a calculator that sort of estimates what you would use. When I put in my estimated gas usage it came back at 56 tons of wood.

Well I ton is approx a cord. So there you go the ool part is the saving even buying wood was still $6000. So yeah a pain but in reality it a lot cheaper.

 

[Guarddog1]

I have a wood master 4400 heating 2300sq foot house plus hot water. I would use about 800 gallons of oil and I would say I have used about 5-8 cords of wood I really do not think that is bad. And a good portion was pine so I would think it would be less if it was all hardwood.

 

[ngzcaz]

Uhh... Trucks come in vastly different sizes, from 1/4 ton to God knows what. The term " truck load " would have to be quantified before any calculation could be determined.. Sorry..

:monkey:

 

[Zodiac45]

Uhh... Trucks come in vastly different sizes, from 1/4 ton to God knows what. The term " truck load " would have to be quantified before any calculation could be determined.. Sorry..

:monkey:

+1 Yep exactly. What's a truckload? Tell me how many cords.

 

[pipe welder]

Well a truck load around my place is a 3/4 ton ford diesel, packed down with all you can load on it. As for the usage, about 30 loads last year and I lost count this year. After 1 and 1/2 seasons I'd had enough, last week in January I tore the whole thing out and installed an indoor wood boiler and am now using about 1/3 the wood I was. I was heating the house and domestic water with the OWB and I am heating the house and domestic with the inside boiler, so it works for me . I put all that other stuff on craigslist, maybe I can get some of my investment back, only time will tell.

 

[twofer]

The addition of more water to a system will not in any way improve its efficiency...

Storing heat is a bad idea unless your using some passive system like solar. You are much better off to just produce the BTU's required as needed.


The new high efficiency boilers (If there is such a thing) in fact have very small water capacity.

Mark

I don't agree with this unless the boiler is sized to the heating load and is running at full combustion the majority of the time. If it is not then he is loosing efficiency due to smoldering and a thermal storage tank would help reduce this. With the thermal storage tank the boiler would end up running at full combustion for longer periods of time and will produce more BTU's from the same amount of wood.