Another IS question

[ambull01]

There isn't too much to update. Everything is working great. It kept me warm all winter. I was impressed with how warm my house was when I came home from work everyday.

Being away 11 hours the Quadra fire 4300 could not cut it and my heat pump was on when I got home. Of course that means the auxiliary came on too everyday.

With the Ideal Steel I was able to set the heat pump at 65 and leave it there. In the coldest parts of the winter it did not kick on. The only time it ran is when I went away for 3 days. Other than that, the Ideal Steel effectively heated my whole house from the basement.

Please note that I also did some major insulating projects prior to this winter that may have improved my results.

Nice. I envy you.

 

[unhdsm]

Instead of figuring out the exact number of hours, this is a better way to think about the IS in a cold climate (New England):
You will have to load it twice/day in the dead of winter, and once/day in the shoulder season. Adjust for your variables.

I know someone who made it almost all winter with once/day loads but that house is super insulated. Mine is insulated pretty well but I needed to keep it above 70 and loading before I left for work and then at 7:30p made it easy. This was the coldest winter in a long time so it shouldn't get much worse. I can handle loading the stove 2 times versus the 5 times I used to with my last stove. When it was -20F or colder we might have put a few pieces in around 3p. I heated 1900 sqft on less than 3 cords this year so I cannot imagine any stove that will use less wood.

I think a Blaze King will have longer burn times though.

 

[Highbeam]

Instead of figuring out the exact number of hours, this is a better way to think about the IS in a cold climate (New England):
You will have to load it twice/day in the dead of winter, and once/day in the shoulder season. Adjust for your variables.

I know someone who made it almost all winter with once/day loads but that house is super insulated. Mine is insulated pretty well but I needed to keep it above 70 and loading before I left for work and then at 7:30p made it easy. This was the coldest winter in a long time so it shouldn't get much worse. I can handle loading the stove 2 times versus the 5 times I used to with my last stove. When it was -20F or colder we might have put a few pieces in around 3p. I heated 1900 sqft on less than 3 cords this year so I cannot imagine any stove that will use less wood.

I think a Blaze King will have longer burn times though.

How do you load once per day when best burn times are under 20 hours? Do you mean start a new fire once per day?

 

[unhdsm]

How do you load once per day when best burn times are under 20 hours? Do you mean start a new fire once per day?

It doesn't sound like we are using the same terminology. After 24 hours I have enough coals to push to the back, fill the stove and let it do it's thing. At 24 hours they aren't putting out much heat but the stone is still warm. Since this is the shoulder season, the sun does most of the warming during the day.

I filled it 90% last night at 7:30p and happened to check this morning at 7:30a and still had recognizable pieces of wood. I had it turned down pretty low all night. If it was the middle of winter I would have run it hotter and it would have been ready to reload.

Interestingly last night I had the coolest looking secondaries I ever saw. Just slow, dancing flames shooting down 2/3 of the window just behind the glass and no where else. It went for at least an hour like that and continued for who-knows how long after I went to bed.

 

[begreen]

Thanks unhdsm for the shoulder season burning update. It sounds like the soapstone sides are working for you to release heat after the fire is low. Would you recommend them to ambull01?

 

[unhdsm]

Thanks unhdsm for the shoulder season burning update. It sounds like the soapstone sides are working for you to release heat after the fire is low. Would you recommend them to ambull01?

It's hard to say without data. I've been trying to get a friend to datalog the stone panels. All I can say is that they do hold some heat, so they can't hurt. With the giant window it isn't like the IS has any issue getting the heat out quick enough even on a fresh start.
My opinion--- If you have the stove for 25 years and they cost $200(?), the extra $8 per year isn't going to kill you.

 

[pdxdave]

I don't think we'll find anybody other than Woodstock that has run both with and without soapstone to compare. I called them and asked and they said there was no difference performance-wise. I didn't get the soapstone liner (but did get the sideplates). My burn times and heat output seem to match pretty much what others are reporting, most of whom have the soapstone liner.

 

[begreen]

I would think that the soapstone panels would soften the side radiance of the stove, but never having run one with and/or without I am just extrapolating the experience I've had going from the radiant Castine to the convective T6 with it's massive castiron side plates.

 

[Grisu]

If you have the stove for 25 years and they cost $200(?), the extra $8 per year isn't going to kill you.

The question I would have is whether the soapstone bricks have a similar lifespan than their firebricks. Over the life of the stove you will probably go through 2 to 3 sets of firebricks. Should the soapstone bricks last longer that would indeed be an advantage.

I am not sure if the soapstone will be really that much better in performance. Its specific heat capacity is only slightly better than firebricks and depending on the source it may have a bit higher density. Together you may look at maybe 20% difference in heat retention at best. Not sure if that will really be noticeable.

 

[flyfish]

Unhdsm,
Can you give us a bit more info on what your using for settings along with your burn times? You say you load twice a day during the dead of winter, can you give us what you are using for air settings to achieve that? Are you loading it up and then closing the air right down tight? I am a new IS owner and still trying to figure out the stove. I understand that my draft, wood, ect may be different, but I think more info on what you doing with your stove may be beneficial. Thanks!

 

[unhdsm]

I use a probe thermometer 18 inches up the stack, and a magnetic thermometer adjacent to the topvent outlet. I found for me it works best to stuff it full and when the surface thermometer reads 500 to 525F (550-600F when it is real cold) shut the bypass and turn the air control down to 1/4.
Now that it is warmer I have the same procedure only I turn the air control down to 1/8.
Some very cold mornings I wake up early and open the air control a couple hours before I refill and that helps to control the ash and get some heat into the house.
After 1.5 COLD winters this is pretty much what I narrowed it down to. Wood is mostly ash and yellow birch. I dust off the cat every month or so with a soft bristled dust pan broom- takes less than 5 minutes.

 

[flyfish]

Thanks for the info. When you say 1/4 is that one 1/4 open? As in 3/4 all the way to the left? I also see that you are closing everything up much later then Woodstock recommends (250 degrees), and maybe this is what I need to help with a bit cleaner burn. I really appreciate the info! Thanks!

 

[unhdsm]

Yes

Thanks for the info. When you say 1/4 is that one 1/4 open? As in 3/4 all the way to the left? I also see that you are closing everything up much later then Woodstock recommends (250 degrees), and maybe this is what I need to help with a bit cleaner burn. I really appreciate the info! Thanks!

No. I just grabbed the manual to try and figure out where that number came from. They want you to close the bypass when the stove pipe surface temp is 250F. I have a probe thermometer (which I advise everyone to get) and that should approximately be 500F at the 250 surface temp. Are you shutting down the air control when the stovetop is 250F? I would go with reading the temp at both places but I almost always use the stovetop temp to determine when to close the air control, and that is at least at 500F.

Also I do mean I shut the air control to 1/4 open- all the way to the left.

 

[ambull01]

Instead of figuring out the exact number of hours, this is a better way to think about the IS in a cold climate (New England):
You will have to load it twice/day in the dead of winter, and once/day in the shoulder season. Adjust for your variables.
I know someone who made it almost all winter with once/day loads but that house is super insulated. Mine is insulated pretty well but I needed to keep it above 70 and loading before I left for work and then at 7:30p made it easy. This was the coldest winter in a long time so it shouldn't get much worse. I can handle loading the stove 2 times versus the 5 times I used to with my last stove. When it was -20F or colder we might have put a few pieces in around 3p. I heated 1900 sqft on less than 3 cords this year so I cannot imagine any stove that will use less wood.
I think a Blaze King will have longer burn times though.

So your shoulder season is probably my dead of winter. Once a day sounds great lol. My insert could only go about 4 hours between reloads. You loaded twice a day and only used 3 cords? I was thinking I would need about cords a year.

don't think we'll find anybody other than Woodstock that has run both with and without soapstone to compare. I called them and asked and they said there was no difference performance-wise. I didn't get the soapstone liner (but did get the sideplates). My burn times and heat output seem to match pretty much what others are reporting, most of whom have the soapstone liner.

I was wondering how it's possible for both soapstone and firebrick to achieve the same max BTU output. If soapstone provides a more even heat output and firebrick is more peaky it sounds like the firebrick achieves the higher max heat. There must be a legit reason why soapstone costs more and is looked upon as the more desirable stove lining material right?

The question I would have is whether the soapstone bricks have a similar lifespan than their firebricks. Over the life of the stove you will probably go through 2 to 3 sets of firebricks. Should the soapstone bricks last longer that would indeed be an advantage.
I am not sure if the soapstone will be really that much better in performance. Its specific heat capacity is only slightly better than firebricks and depending on the source it may have a bit higher density. Together you may look at maybe 20% difference in heat retention at best. Not sure if that will really be noticeable.

Isn't firebrick a lot cheaper than soapstone? If it is, the soapstone would have to last a lot longer just to make up for the initial price difference right?

 

[Dairyman]

I was wondering how it's possible for both soapstone and firebrick to achieve the same max BTU output. If soapstone provides a more even heat output and firebrick is more peaky it sounds like the firebrick achieves the higher max heat. There must be a legit reason why soapstone costs more and is looked upon as the more desirable stove lining material right?

The majority of the heat release will come through the glass and the stovetop. No soapstone there on the IS. Soapstone on the floor won't be of benefit for heat retention especially with a layer of ash. So your left with the sides and rear for heat buffering.

Is it worth the premium? Probably not. But it is pretty to look at.

 

[JA600L]

There is no soapstone on the floor. They use regular firebrick for that.

Either decision you make will be fine.

 

[Highbeam]

Didn't Woodstock already say it makes no performance difference? Why fight it. The stone is just for looks.

 

[stephiedoll]

Be also aware that when people talk about 30+ hours they really talk about a LOW heat output in the 10,000 BTU per hour range. I doubt that will be enough for the size and age of your home unless it is in the fifties outside. Realistically, I would expect burn times of maybe 10 hours during winter even with the IS. There are only that many BTUs in 3 cu ft of wood.

I like this response. As I understand it, wood has about ~8,000 btu's per pound. Hardwood or softwood are the same. Hardwood is denser so you can fit more pounds in the firebox. If you have a drafty house, you WILL need lots of btu's to heat it.

I know it's not cheap (started working on the attic last year), but you need to work on the drafts. I need to get back up in my attic and try to get it finished up before it gets hot up there. I am also upgrading my Quad 2.0 cf stove to the IS (still working on designs). My invoice for the works with the rear heat shield and shipping was around $2,500 shipped to the dock for me to pick up. I would have liked to get a BK but just could not see spending the money since I have NG.

 

[JA600L]

The potential btu amount will be the same as any stove of the same firebox size. The difference is how those btus are extracted. Or how many of them go up the stack as smoke .


Consider a piece of rope with a 90 degree bend. The longer one side is the shorter the other.

It is always give or take. You make one side shorter then the other side is longer. The same goes for btu extraction. If you extract less btus at a time then there is more to be extracted later.

Running on a lower output gives you more burn time. Running on a higher output is less burn time. How the stove handles this task is very important to the success of heating your house.

I
I______

I_________

 

[pdxdave]

The potential btu amount will be the same as any stove of the same firebox size. The difference is how those btus are extracted. Or how many of them go up the stack as smoke .


Consider a piece of rope with a 90 degree bend. The longer one side is the shorter the other.

It is always give or take. You make one side shorter then the other side is longer. The same goes for btu extraction. If you extract less btus at a time then there is more to be extracted later.

Running on a lower output gives you more burn time. Running on a higher output is less burn time. How the stove handles this task is very important to the success of heating your house.

I
I______

I_________

I agree but the 'how many go up the stack' question is waaay underplayed here. That is a huge piece of the puzzle and one that box size, burn times, epa ratings give us basically no clue.

 

[Highbeam]

I agree but the 'how many go up the stack' question is waaay underplayed here. That is a huge piece of the puzzle and one that box size, burn times, epa ratings give us basically no clue.

A probe meter measuring flue gas temps and a knowledge of the size of the combustion air inlet allows you to know more. Most importantly, the woodstock and BK have had their stoves tested for efficiency. Real efficiency for heat delivered to the room, not combustion efficiency which is for emissions.

At low burn rates, the cat stoves are at peak efficiency. It tails off as the burn rate goes up since more heat is flowing up the stack and smoke rushes through the cat. Still nowhere near as wasteful as a non-cat at any burn rate.

What I want (and found with BK) is a stove that provides high efficiency, a large fuel tank for long reload intervals, and a low burn rate so I don't get overheated in my small home. The IS is pretty good at that too along with significant cost savings up front.

Heck, if the king model (4.3? CF) could be dialed down to a low enough burn rate I would appreciate a 40 hour burn rate even more than 30. Maybe only load once a week if they had a 10 CF model. Almost like a furnace.

 

[JA600L]

http://firewoodresource.com/firewood-accessories/soapstone-firebrick/

you might find this helpful.

 

[ambull01]

The majority of the heat release will come through the glass and the stovetop. No soapstone there on the IS. Soapstone on the floor won't be of benefit for heat retention especially with a layer of ash. So your left with the sides and rear for heat buffering.
Is it worth the premium? Probably not. But it is pretty to look at.

Okay, so that makes sense how the addition of soapstone doesn't decrease the maximum BTU output.

A probe meter measuring flue gas temps and a knowledge of the size of the combustion air inlet allows you to know more. Most importantly, the woodstock and BK have had their stoves tested for efficiency. Real efficiency for heat delivered to the room, not combustion efficiency which is for emissions.
At low burn rates, the cat stoves are at peak efficiency. It tails off as the burn rate goes up since more heat is flowing up the stack and smoke rushes through the cat. Still nowhere near as wasteful as a non-cat at any burn rate.
What I want (and found with BK) is a stove that provides high efficiency, a large fuel tank for long reload intervals, and a low burn rate so I don't get overheated in my small home. The IS is pretty good at that too along with significant cost savings up front.
Heck, if the king model (4.3? CF) could be dialed down to a low enough burn rate I would appreciate a 40 hour burn rate even more than 30. Maybe only load once a week if they had a 10 CF model. Almost like a furnace

So are BK stoves owned predominately in mild climates?

http://firewoodresource.com/firewood-accessories/soapstone-firebrick/
you might find this helpful.

Thanks. So bottom line is soapstone may be the better fit if you're away from home longer than the ideal reload time(s) and for the shoulder season. I guess I'm getting the works. I don't like how the top of the stove looks with all that fancy stuff though.

 

[Highbeam]

So are BK stoves owned predominately in mild climates?

Not at all, they have large market share in cold places like Alaska where you really need the fire to stay going while you're away. Higher outputs mean lower burntimes but you need to understand that keeping a house warm is much different than heating it up. You're getting a pretty long burning cat stove so you will be able to experience this "keep it warm" shift in operation.

I have a non-cat in the shop and it is run at full output to warm up the shop when I plan to spend time out there. That is one reason for a non-cat in that building, there is no reason to idle the shop stove.

 

[rideau]

Just get a soapstone slab top made to cover the appearance you don't like. You'll have a darn pretty stove, and one that retains and slowly delivers a bit more heat. Win, win.