Production Woodstock IS

I don

I don't even have my t-stats turned on. The stove is only warm to the touch and coals are all down to dust. I do believe my house construction is unique exploiting the efficiency of the IS.

 

Hollywood , you are quite the exception, and most of us IS folks know you get incredible results from the way you burn and the way your home is setup. There are no contradictions.

 

It seems like we are telling two different stories but not really- we are just using our stoves differently and getting and I guess, expecting, different results.
I live in a pretty old house and while most of it has now been re-habbed, I could not even guess to its insulation value. I also run my house warmer than Hollywood, and believe me, increases in temperature really take a LOT more energy to raise the inside temp., say, 5 degrees F from 70 F to 75F when it is, again say, 15F outside.

This whole woodstove burn time reminds me of EPA mileage eastimates.... they simply do not apply to the real world. Of course they get away with their figures by claiming your mileage may vary but really, their numbers are pretty useless and often worse than that, misleading to prospective customers.

Let's approach this a little differently: How about we look at how much energy it takes to heat a person's home to his / her desired comfort level. Just for example, say during the hardest part of the winter a house goes through 200 gallons of #2 fuel oil in 30 days (not an unreasonable estimate IME). That would be 6.7 gals. per day and probably more used at nighttime than during the day. There are 138,000 BTU in a gallon of fuel oil, and let's figure an overall efficiency of 86%: so 920,000 BTU of heat was produced, and 791,200 BTU ended up in the house. Now that is the magic number: it takes approx. 800K BTUs to heat our imaginary house.

Now to compare this with wood: Hardwood weighs about 4,500 lb. per cord, and has about 20,000,000 BTU; so a pound of dry hardwood will produce approx. 4,500 BTU of heat. Assume an efficiency of 85% for the overall stove and installation, again a reasonable figure IME for a modern, cat. based stove, and you will require 791,200 / (4,500 * 0.86) = 204.5 lb. of hardwood on the coldest days to heat the house. This seems close to reasonable to me, at least w/in the realm of possibility. Now a really big stove, such as the Blaze King (King model) has a 4.4 cubic foot firebox that Blaze King will hold 90 lb. of wood. So you would have to load the Blaze King twice a day full and maybe a mid- day feeding of, say, 1/2 load of wood to heat our theoretical house.

You would need a firebox capacity of approx. 10 cubic feet to heat a house in a cold environment for 24 hours and there are no woodstoves that I know of that will hold that amount of wood. The next step would be a wood fired (gassifier) boiler, coupled with water storage, fired once a day to take care of a 24 hour cycle of heat needed. Which is why there are so many wood fired boilers out there.

Of course there may be errors in the above and I would appreciate anyone adding any corrections. But I do not believe my theoretical overview is off sufficiently that the largest woodstove made will heat a house in Nebraska (a reasonable, real- world house, heated to a decent temp. such as 70F) on one load of fuel per day.

Brian

 

Agreed on all counts. I'm an auto tecnition by trade and fielded countless questions about fuel milage ratings on the window sticker. Highway and city they rate. Most people assume "highway" is the interstate we all drive at 65+, but in actuality there "highway" is are the old Maine roads that run between and threw all the towns with the speed limits at 55 between the towns. There tests are at 55mph. The amount of extra fuel needed to run only a little faster is exactly what Brian stated about getting a few more degrees of house temp.

I am finally able to say I am on top of the grading curve as far as allround performance no longer on the lower end of the curve getting mad at the kids who did there homework and got the good grades like I was supposed to.

 

If you want a stove that effectively heats your house 24 hours in the cold winter the answer is it will not. Maybe it will, but don't plan on it doing that. This stove will give you 10-16 hours of good usable heat in cold weather. Burning really dense woods will prolong the coal stage and if you have good insulation it might carry you 24 hours with moderate cold weather. All things considered, it will blow away that stove you have now.

I loaded the stove full to the max with 3 year dry white oak chunks at 1:30 this afternoon. I engaged the cat and ran it hot until 2:00. I set the air control to notch #2 and left it alone. It is now almost 9:00 and the temperature dial in front of the cat only moved a little bit. It is 375 degrees right in front of the cat with an IR temp gun.
I shone a flash light in there and it looks like I just loaded it 5 minutes ago. I turned the air control up to notch #4 for a little bit to bring the heat up a bit then set it back to notch #2 I'm going to let it ride tonight.

 

#2 really is a winner if you can harness it. I believe this will be where I will spend most of my shoulder season. It has been cruising for over 8 hours now with the cat active. My thermostat upstairs is 70 degrees and its 35 outside. Initially, I wanted to run with the air control fully closed but this stalled the cat. Thats the second trial run where the cat stalled so I won't be attempting that anymore.

 

Without taking the time to look things up to check, I think your figures are off. The moderately dense hardwoods like Beech and Sugar Maple I believe weigh perhaps 3700 pounds per cord and contain about 23 - 24 M BTU. A significant difference. The generally used figure for BTU per pound is about 8000 BTU, at 20 % moisture content delivered heat is, I think, about 6500 BTU per pound. 6500 BTU per pound x 90 pounds = 585 ,000 BTU.

 

Sorry, I was away on a retreat all weekend Lovinwood and I'm just getting caught up.

I've never owned a Blaze King, but they have an excellent reputation and many satisfied customers. Other than joking about their looks, you simply will not find me criticizing Blaze King products. If your #1 goal is long burns, the Blaze King King is king. The Woodstock IS can't compare, as the BKK has a much larger firebox, as others have already noted.

My 24 hour burn was just done as a proof of concept. It would work fine in a well insulated home in the shoulder season. In our drafty old house, it would have to be in the 40s during the day and the 30s at night for that 24 hour burn to provide adequate heat output without my natural gas furnace kicking on.

Even with a Blaze King King, unless you have an exceptionally tight small house, you are not going to heat it for 40 hours in the dead of winter on one load. A 4 cu ft load of wood only releases so many BTUs, and a stove can only transfer the heat of a portion of those available BTUs into the interior of the house. Some heat goes up the chimney of every wood stove, no matter how technologically advanced it might be.

We generally load our stove on a 12 hour basis with good hard wood, sooner with cherry and during bitter cold and windy days. We use our natural gas hot water furnace as a backup and to keep the heat in the house evened out. We do not heat solely with wood. I would need a second stove in my basement (primarily to keep one pipe to a rear first floor bathroom from freezing) if we were to heat solely with wood.

I'm very pleased with our stove, no regrets. Its exceptionally easy to operate, very predictable and repeatable, and we get many compliments on the looks.

But in normal use, with rare exceptions already discussed in this thread, its not a 24 hour burner for us.

The next Beta Franklin Hybrid will have a smaller firebox, around 2.5 cu ft compared to the Ideal Steel's 3.2.

Again if you're primary concern is long burns, then you need the biggest firebox available.

 

Well folks here we are at the 16 hour mark. Unfortunately, I have to go to work so I can't play anymore. I'll probably add to this load to get me 11 more hours.

 

Are you loading the wood vertical?

 

Very good information Brian. Thank you. This site is awesome. When we joined we had in mind the Ideal Steel maybe being the stove for us because of it's stellar efficiency. It might still be but the honest assessments of burn time (or heating our home time) has raised more questions for us. We are still trying to figure out this efficiency thing but we are learning.

 

OK, that may well be correct info. Given your figures, with high efficiency of something like 85% or even 90%, that is still not nearly enough to heat an average house for 24 hours in cold climates.

I do not believe a woodstove will heat a normal house in Nebraska for 24 hours in the winter. It is just a matter of not being able to get enough potential energy (the fuel, wood in our case) into the device (the stove) to last that long putting out sufficient heat to maintain, say, 70F and a little bit more.

To do that, I believe a wood furnace or wood boiler will be needed. A quick look at this page: http://www.alternateheatingsystems.com/wood-gun.html shows that their smallest firebox on the gassifier line of boilers is 6.5 cu. ft. but quickly moves up with the largest one being 22 cu. ft. I personally would choose the second boiler (E140 model) as a reasonable source of heat for my home using one loading / firing cycle for 24 hours of heat as well as domestic hot water, and the firebox on that boiler is 10 cu. ft.. Far, far larger than any woodstove that I am aware of.

Brian

 

Actually our friends do heat their homes with Blaze King for 24+ hrs. even with the smaller 2.75 cf firebox. Our friends with the King model (4.3 cf firebox) will heat their 1600 sf home for 30+ hours burning hardwood even when the temps are in the single digits. And they don't use any form of backup heat. That would be a really good option for my wife and I except she doesn't like the looks. Got to keep her happy. That is why we were hoping the Ideal Steel would have burn times similar to that. Still trying to figure out why it doesn't when it has a bigger firebox (3.2 cf) and the efficiency is rated higher than Blaze King.

 

Ah, I think I understand now.

Brian

 

Does your wife also not like the looks of the Ashford 30?
Much more "traditional" look to that one.
It's on my short list......as is the IS.

 

I suspect the answer to that is the design. Blaze King was designing a stove for a long burn, and their designs are a number of years old now. Woodstock designed this IS stove to get ahead of the new EPA regulations for clean burning, not for long burns. Those clean stats have to occur at both high rates of burn and low rates of burn. I think you can design for long burns or for the new EPA regulation but given present technology I don't know if you can do both.

 

Actually the deeper we get into this the more we are leaning towards the Ashford 30.

 

This is starting to make alot more sense! Our thanks again.

 

Just looked at their website. The Ashford 30 and Sirocco 30 are both nice looking stoves. Looks like the burn times would be very similar to the Princess, maybe a little less. But the biggest surprise is that they are both rated at .97 gr/hr for the emissions. Until today, we didn't know there were stoves that burned cleaner than the Ideal Steel (although they are virtually the same). So it looks like long burns and clean burning might be possible with these stoves.

 

Thought I would post up a picture, I was shoveling the back deck again!
This snow in New England just seems to keep coming.
The first time I've seen this on my chimney, Icicles. this IS just holds on to the heat.
My EPA Phase II, Lopi stove has never done that.
This with the cat at 750, stove top temp at 550 and pipe at 250.
Starting to push into longer burns with a passive mod I have made, still in the experimental stage.
Though I really don't need the longer burns, just the engineer in me I guess.
I love this stove.