Running the new Mansfield 8013

[bholler]

Setup is simple:

View attachment 306812

Straight shot of stove pipe ~13' to the bottom of the support box. Another ~8-9' of straight class A chimney system from there.

This stove calls for 13' - 27' of total chimney system vertical height from the top of the stop.

We are right in the middle of the recommendation and at 7400' elevation. With elevation correction considered we're probably at the lower end of the range of "effective" chimney height.

I bought a vacuum gauge but it doesn't seem to work right.

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On double wall, both stoves ran like a nuclear power plant without enough control rods to manage the reaction. Allowing EGT's to creep above 600-700F could be the beginning of a non-reversable uncontrolled over-fire.

Saw red on the steel stove and had measured surface temps on the soapstone over 650F.

Required constant supervision, smaller fuel loads, and adjustments to keep in check on both stoves, often full-choke, but of course, later in the burn they would both have to be opened back up in order to complete the burn cycle cleanly.

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On single wall, full loads of wood burn through at the manufacture recommended air control settings without any adjustments required after the start-up process, while maintaining ideal temps through the burn cycle, all while putting more heat in the house. It's repeatable and can be trusted while sleeping and leaving for work.

So you didn't check your draft and add a damper to get it without in specifications? No matter what the stove or pipe is you need the proper draft on a straight run like yours I would always install a damper. Yes double wall pipe will increase draft a little bit. Apparently in yours that was enough to put you over the recommended draft. But honestly in many ways that is a good thing. It means you can run at higher outside temps. It means it will get up to operating temp faster and many other benefits. You then simply close the damper and it will run as it should

 

[BKVP]

So you didn't check your draft and add a damper to get it without in specifications? No matter what the stove or pipe is you need the proper draft on a straight run like yours I would always install a damper. Yes double wall pipe will increase draft a little bit. Apparently in yours that was enough to put you over the recommend draft. But honestly in many ways that is a good thing. It means you can run at higher outside temps. It means it will get up to operating temp faster and many other benifits. You then simply close the damper and it will run as it should

Frequently, higher draft numbers also allow for cleaner burning on the low burn settings as well.

 

[bholler]

Frequently, higher draft numbers also allow for cleaner burning on the low burn settings as well.

Yes on some stoves absolutely, on others it will not let you run on the lower end

 

[mdocod]

So you didn't check your draft and add a damper to get it without in specifications? No matter what the stove or pipe is you need the proper draft on a straight run like yours I would always install a damper. Yes double wall pipe will increase draft a little bit. Apparently in yours that was enough to put you over the recommended draft. But honestly in many ways that is a good thing. It means you can run at higher outside temps. It means it will get up to operating temp faster and many other benefits. You then simply close the damper and it will run as it should

I tried to check the draft and failed. Decided to try the single wall as that's what the Hearthstone dealer/installer here recommended in this application with this stove based on their experience with other similar stoves and the type of wood most of us burn around here.

It's not "simply close the damper" to a family member who might want to be able to run this by themselves. The system needs to be simple to operate and adding a 3rd control to the system may seem simple to you or me, but that can take it over the edge for someone who doesn't have the sort of enthusiasm you or I do for these things. The damper would have to be opened every time the door is opened and and re-positioned into the right position at some point during the building stages. If you start trying to explain this process to a layperson...

Then this lever, then that lever, then this knob, then this other knob, no like this, here let me show you it needs to line up just like this or else it explodes...

I hear a lot of talk about how double wall is supposed to "improve" the performance of a stove. By what measure? I get more heat in the house with the stoves peak surface temps at 550F now, than I did with it overfiring at 650F before. There is no scenario here where the double wall could put more heat in the house than the single wall without overfiring the soapstone even further than it already had been. Honestly the stove felt like a under-performer in the BTU department on the double wall. Hot stove in a cold house no matter how much wood I fed it.

"Performance" can be described as how well the system self-automates a burn cycle with a simple set of inputs. With single wall the performance in this category is very high because the higher the EGT's go the more heat-sink effect the stove pipe has. It's like having a thermostatically controlled damper, but without the mechanics. It's all passive thermodynamics at work.

 

[bholler]

It's not "simply close the damper" to a family member who might want to be able to run this by themselves. The system needs to be simple to operate and adding a 3rd control to the system may seem simple to you or me, but that can take it over the edge for someone who doesn't have the sort of enthusiasm you or I do for these things. The damper would have to be opened every time the door is opened and and re-positioned into the right position at some point during the building stages. If you start trying to explain this process to a layperson...

Really? My daughter has been able to run my stove and my father's stove since she was 11. My son who is now 10 just learned this year. It's a damper come on man watch the pipe temp. And adjust accordingly. And writen instructions next to the stove work wonders with diagrams.

Performance" can be described as how well the system self-automates a burn cycle with a simple set of inputs. With single wall the performance in this category is very high because the higher the EGT's go the more heat-sink effect the stove pipe has. It's like having a thermostatically controlled damper, but without the mechanics. It's all passive thermodynamics at work.

I am sorry but that is just not how a stove should be run period. Set your stove up properly and run it properly and the double wall pipe would be an improvement. That's why so many manufacturers recommend it for their stoves.

hear a lot of talk about how double wall is supposed to "improve" the performance of a stove. By what measure? I get more heat in the house with the stoves peak surface temps at 550F now, than I did with it overfiring at 650F before. There is no scenario here where the double wall could put more heat in the house than the single wall without overfiring the soapstone even further than it already had been. Honestly the stove felt like a under-performer in the BTU department on the double wall. Hot stove in a cold house no matter how much wood I fed it.

Maybe if you had a steel or cast stove that can actually handle some real heat in the stove body you wouldn't need to use the pipe to radiate heat.

Sorry but I couldn't resist that one

 

[3650]

My chimney has such a strong draft I have to use two dampers in it. I am at the mercy of my chimney.

 

[bholler]

My chimney has such a strong draft I have to use two dampers in it. I am at the mercy of my chimney.

The chimney at my old house was like that. Almost 40' tall

 

[mdocod]

Maybe if you had a steel or cast stove that can actually handle some real heat in the stove body you wouldn't need to use the pipe to radiate heat.

Sorry but I couldn't resist that one

That last one was actually going to be my next point, because you've been making a case for why this stove might be well suited to drive this stove pipe configuration for a long time. No concern about feeling like you needed to "resist" anything. You've pointed out, and rightly so, many times, that soapstone is an inferior material for thermal transfer, so by your own logic this stove should be expected to drive more heat up the pipe and be in a better position to "drive" a slightly-longer-than-normal section of single wall to good effect. You can't have it both ways. Either soapstone is really amazing, and adding any more heat extraction to the system would be a bad idea, or it isn't, and it could really use the help of some single wall to get the heat into the house that it failed to. You can't have this one both ways.

More to consider:

1. There is no code here that prevents the installation of 13' of single wall above this stove.
2. There is nothing in the Mansfield manual that objectively prohibits the use of 13' of single wall above this stove. There are subjective implications that long installations of single wall (long is not defined) should be avoided.
3. There is nothing in the DuraBlack stove pipe or DuraTech chimney system installation manuals, or brochure, or product specification, that would indicate that 13' of single wall is not allowed with this product.


And again, someone has to explain to me how a 1.2 cubic foot TN10, made from more conductive steel, can safely drive 10' of single wall, while a 2.9 cubic foot Mansfield, made from less conductive stone, can't safely drive 13' of single wall. These 2 things can't exist in the same universe beholden to the same set of physics, yet, according to many people on this forum, these 2 things absolutely do exist at the same time. It's an absurdity of baffling proportions. It's a perfect summary of our modern world and what it has done with common sense.

 

[mdocod]

Really? My daughter has been able to run my stove and my father's stove since she was 11. My son who is now 10 just learned this year. It's a damper come on man watch the pipe temp. And adjust accordingly. And writen instructions next to the stove work wonders with diagrams.

Wait, I thought you had a BK stove... you know, the stoves that have an automatic system built in that reacts to temperature to automatically adjust air flow so that the user doesn't have to... So in reality, your stove systems operation has been simplified to the same level of my stove system by having a component that provides an automated feedback loop to correct for changes in temperatures.

Again, you don't get to have the double standard. Remove the automation from your stove system, then re-write the instructions that are next to your stove to include the constant supervision and adjustments necessary. Then talk to me about adding a damper on double wall.

 

[mdocod]

If all that wasn't enough reason to use single wall in this application, we ALSO have reports, from members on this forum, of these new Hearthstone cat-stoves blowing their top stones or top-plates right off when they back-puff badly, and the installation and use of a damper appears to be a common factor in creating the conditions necessary for this to occur.

One of the things I noticed on double wall, was that when operated at the very low air-control settings required to keep it in check, it would often devolve into back-puff-cycling, which would puff smoke out of some tiny gaps between some of the top stones, and back out the air intake system. I actually suspect that a back-puff may have been the cause of some of those stones no longer being sealed up on top.

Since switching to single wall, the stove can be operated throughout the burn cycle at air-control settings and with fuel loads that burn through most of the wood gases before the flames go out, significantly reducing the propensity of the stove to back-puff. Now, sometimes, a wave of flames will slowly propagate through the stove on and off very gently, not causing a positive pressure situation in the box.

Adding a damper to the double wall may well have turned that problem from an annoyance into a serious safety issue.

 

[bholler]

That last one was actually going to be my next point, because you've been making a case for why this stove might be well suited to drive this stove pipe configuration for a long time. No concern about feeling like you needed to "resist" anything. You've pointed out, and rightly so, many times, that soapstone is an inferior material for thermal transfer, so by your own logic this stove should be expected to drive more heat up the pipe and be in a better position to "drive" a slightly-longer-than-normal section of single wall to good effect. You can't have it both ways. Either soapstone is really amazing, and adding any more heat extraction to the system would be a bad idea, or it isn't, and it could really use the help of some single wall to get the heat into the house that it failed to. You can't have this one both ways.

More to consider:

1. There is no code here that prevents the installation of 13' of single wall above this stove.
2. There is nothing in the Mansfield manual that objectively prohibits the use of 13' of single wall above this stove. There are subjective implications that long installations of single wall (long is not defined) should be avoided.
3. There is nothing in the DuraBlack stove pipe or DuraTech chimney system installation manuals, or brochure, or product specification, that would indicate that 13' of single wall is not allowed with this product.


And again, someone has to explain to me how a 1.2 cubic foot TN10, made from more conductive steel, can safely drive 10' of single wall, while a 2.9 cubic foot Mansfield, made from less conductive stone, can't safely drive 13' of single wall. These 2 things can't exist in the same universe beholden to the same set of physics, yet, according to many people on this forum, these 2 things absolutely do exist at the same time. It's an absurdity of baffling proportions. It's a perfect summary of our modern world and what it has done with common sense.

I agree double wall isn't required by code and I never said it was. I never said it was safe or unsafe. I simply said in my experience (which covers hundreds of stoves) double wall almost always improves performance

 

[bholler]

Wait, I thought you had a BK stove... you know, the stoves that have an automatic system built in that reacts to temperature to automatically adjust air flow so that the user doesn't have to... So in reality, your stove systems operation has been simplified to the same level of my stove system by having a component that provides an automated feedback loop to correct for changes in temperatures.

Again, you don't get to have the double standard. Remove the automation from your stove system, then re-write the instructions that are next to your stove to include the constant supervision and adjustments necessary. Then talk to me about adding a damper on double wall.

I do in the house. And a Fisher in an outbuilding (which she can run) and my father has a PE that she can run.

And the bk is no easier or harder to run than the regency I had sitting there before. Once the air is set. I don't touch it.


Ultimately we are talking about your stove you do what works best for you providing it's safe (which I see nothing unsafe there) I am glad you figured out what works best for you

 

[bholler]

Adding a damper to the double wall may well have turned that problem from an annoyance into a serious safety issue.

How would it do this?

 

[mdocod]

How would it do this?

The running theory is that the damper creates a more restrictive "chamber" where wood gases are more likely to accumulate to ideal detonation ratios.

 

[bholler]

The running theory is that the damper creates a more restrictive "chamber" where wood gases are more likely to accumulate to ideal detonation ratios.

Not if the draft is correct

 

[mdocod]

Not if the draft is correct

Or maybe the draft was perfect, and then it wasn't, because burning wood is an imperfect process with lots of fuel related variables.

 

[bholler]

Or maybe the draft was perfect, and then it wasn't, because burning wood is an imperfect process with lots of fuel related variables.

So what would cause those drastic fluctuations in draft?

 

[jpm995]

That last one was actually going to be my next point, because you've been making a case for why this stove might be well suited to drive this stove pipe configuration for a long time. No concern about feeling like you needed to "resist" anything. You've pointed out, and rightly so, many times, that soapstone is an inferior material for thermal transfer, so by your own logic this stove should be expected to drive more heat up the pipe and be in a better position to "drive" a slightly-longer-than-normal section of single wall to good effect. You can't have it both ways. Either soapstone is really amazing, and adding any more heat extraction to the system would be a bad idea, or it isn't, and it could really use the help of some single wall to get the heat into the house that it failed to. You can't have this one both ways.

More to consider:

1. There is no code here that prevents the installation of 13' of single wall above this stove.
2. There is nothing in the Mansfield manual that objectively prohibits the use of 13' of single wall above this stove. There are subjective implications that long installations of single wall (long is not defined) should be avoided.
3. There is nothing in the DuraBlack stove pipe or DuraTech chimney system installation manuals, or brochure, or product specification, that would indicate that 13' of single wall is not allowed with this product.


And again, someone has to explain to me how a 1.2 cubic foot TN10, made from more conductive steel, can safely drive 10' of single wall, while a 2.9 cubic foot Mansfield, made from less conductive stone, can't safely drive 13' of single wall. These 2 things can't exist in the same universe beholden to the same set of physics, yet, according to many people on this forum, these 2 things absolutely do exist at the same time. It's an absurdity of baffling proportions. It's a perfect summary of our modern world and what it has done with common sense.

I have a True North TN10, the firebox is even smaller than you stated. It's only .8cf [only takes about 12" long splits, it's a pain].

 

[mdocod]

I have a True North TN10, the firebox is even smaller than you stated. It's only .8cf [only takes about 12" long splits, it's a pain].

Sure enough! I must be thinking of another stove. Dang that would be a perfect little stove for a cozy, short-burn fire in a bedroom or study or something.

 

[BKVP]

Sure enough! I must be thinking of another stove. Dang that would be a perfect little stove for a cozy, short-burn fire in a bedroom or study or something.

Fire prevention codes prohibit solid fuel appliances in bedrooms...just an FYI. I've seen them in Yurts!

 

[jpm995]

It's my first wood stove and i'm still in learning mode. Heats up my little 200sq ft, 12x18 shed/gym pretty well. A neighbor's tree fell on it, taking out the roof, i'm still in rebuild mode. I'm old it's taking forever.

 

[mdocod]

Fire prevention codes prohibit solid fuel appliances in bedrooms...just an FYI. I've seen them in Yurts!

We drew wood stoves into the 2 larger bedrooms here at the custom home we're currently living in. The architect who took our sketches and computer models made engineered/stamped blueprints/plans to be submitted to regional had no concerns about the stoves in the bedrooms being a code issue. They've been designing custom homes in the region for 40 years and are a highly regarded architecture/engineering company. They know their stuff. Our builder, who has built dozens of custom homes and remodeled hundreds had no concerns about there being a code issue with that. Our regional building department approved the plans with the wood stoves clearly shown in them and called out in the notes without even batting an eye, and lastly, code actually makes an exception for wood stoves, which is why nobody in this chain of homebuilding planning/engineering/building/code-compliance experts raised an eyebrow over it.

 

[bholler]

We drew wood stoves into the 2 larger bedrooms here at the custom home we're currently living in. The architect who took our sketches and computer models made engineered/stamped blueprints/plans to be submitted to regional had no concerns about the stoves in the bedrooms being a code issue. They've been designing custom homes in the region for 40 years and are a highly regarded architecture/engineering company. They know their stuff. Our builder, who has built dozens of custom homes and remodeled hundreds had no concerns about there being a code issue with that. Our regional building department approved the plans with the wood stoves clearly shown in them and called out in the notes without even batting an eye, and lastly, code actually makes an exception for wood stoves, which is why nobody in this chain of homebuilding planning/engineering/building/code-compliance experts raised an eyebrow over it.

Yes it gives an exception for woodstoves if the bedroom is not a confined space or the home is old and leaky.

Just because a code office misses something doesn't change the code. Just because an architect has been ignoring code for 40 years doesn't change the code. It's all there in print.

Can you show us the exception you are talking about?

 

[mdocod]

Yes it gives an exception for woodstoves if the bedroom is not a confined space or the home is old and leaky.

Just because a code office misses something doesn't change the code. Just because an architect has been ignoring code for 40 years doesn't change the code. It's all there in print.

Can you show us the exception you are talking about?

Not until you stop replacing the words "not unusually tight construction" with "old and leaky"

You're coming to the table with a mischaracterization of the very code you posted on this forum, so there's really nothing left to argue other than your interpretation of it, not what it actually says.

This home, that could have been built to code with wood stoves in bedrooms also had to pass a leak-test to ensure that the structure was not excessively leaky.

 

[bholler]

Not until you stop replacing the words "not unusually tight construction" with "old and leaky"

You're coming to the table with a mischaracterization of the very code you posted on this forum, so there's really nothing left to argue other than your interpretation of it, not what it actually says.

Ok so it wasn't an exact quote. It doesn't change the meaning of the code. Can you tell us what exemption you are referring to?