Minimum Installation Clearences - Really?

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BurnIt13

Minister of Fire
Jun 10, 2010
636
Central MA
Please bear with me....a bit of history 1st.
I have a 1500sq.ft. 110 year old house that up until this year was not insulated except for the attic which was poorly done. Three years ago with the help of this forum I bought and installed an Englander 30 stove. It was done per the manual and was inspected by the building inspector and insurance company.....no problems.

I installed close to the minimum installation clearances. The Englander 30 manual says that the minimum side clearance on a protected surface is 12" when side shields and double wall pipe are installed. I am using stove board as the protected surface to protect the wall.

I installed the stove 13.5" away from the wall and 12.5" away from the stove board. The stove board being used to protect the wall is spaced away from the wall with 1" ceramic spacers and the board itself is 1.5" spaced off of the floor. The top of the stove board is about a foot higher than the top of the stove.


Okay....back to the question.
In my opinion the wall still gets way to hot. The portion of the wall above the stove board has measured as high as 180 with an IR temp gun. The stove board directly near the side of the stove has measured well above 200. This is with the 30 going full tilt with a surface temp of 800+ and with the fans off. When I turn the fan on, the stove top and wall temps come down a bit.

So I'm wondering......does the Englander 30 throw a TON of heat off of its sides compared to many other stoves?


Why do I ask???
This summer I embarked on a large project and my 1500 sqft. home is now properly insulated and air sealed. The 30 is going to be way too much stove. The hearth I built is a bit large as well and the whole installation takes up more space than I'd like in the room.

If I move to a smaller stove (like a BK Sirocco/Chinook 20), I can install a much smaller hearth pad. This will give me much more floor space which I really desire.

The Sirocco/Chinook 20 require about 10.75" of side clearance, on an unprotected surface.

The Million Dollar Question:
Do smaller stoves like the BK's mentioned above put out a lot less heat out their sides when compared to an Englander 30? If I were to install the BK's at say, 11-12" of side clearance.....would my now unprotected wall be hotter or cooler than it is now? Anyone have experience in a situation like this?

Sorry for the long post, I just wanted to get all the details in there. Thanks in advance!
 
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Sounds like you want the 30NC rear and side heat shields for reduced clearances. They are optional.
 
Sounds like you want the 30NC rear and side heat shields for reduced clearances. They are optional.

Ummmm, thank you for the reply but that isn't nearly what I was asking.

I have the rear and side heat shields, in addition to a fan and a protected wall surface. I'd like to move to a smaller hearth and stove. The stove I am interested does not require wall protection at the same installed clearance that I currently have.

I'm wondering if the 30 is just a heat monster and throws a lot of heat off of its sides when compared to other stoves like the smaller BK's.
 
The NC30 throws a lot of heat off the sides compared to any BK cat stove. Way more. The 30 is single wall steel with just firebricks on the bottom half or so of the box. The BK has interior side shields or brick all the way to the top of the firebox as well as most models include an exterior sideshield/skin. The BK is built as a convection stove and makes very little radiant heat out of the sides, back, and bottom. You can see this by looking at the much lower clearance requirements and only ember protection on the hearth.

The other thing is that, especially in 1100SF, you won't be running the BK as hot as you are with the 30. No 800 degree stove will happen.

Most importantly, the BK is a cat stove. The majority of its heat output comes from the cat which is top, forward, and center. The paint in that area will fade and that area will be hot. Not the sides. The actual fire makes very little heat, especially when running in a small home at moderate output.

The NC30 is a great stove when you need as much output as you were getting with that stove at 800 degrees, you were really getting some heat. It is built to be run hard and the whole dang thing gets hot. You don't need or want that anymore in that small home.
 
Thank you. Because of the small, now insulated home and my desire for longer burn times....I am focusing on the cat stoves. BK's are definitely where its at.

I have excessive draft so even when shut down with a full load of dry wood the NC30 would burn in the 700's when the secondaries light off. I have to try hard to stay ahead of it.
 
I agree with everything Highbeam said, but will augment his response to say that these clearances are likely based on your wall achieving a certain temperature, such that if each stove is installed at its respective minimum clearances, then your wall will probably achieve the same temperature, in instances where you're running each stove hard. I believe this is the answer to your original question.
 
Thank you. Because of the small, now insulated home and my desire for longer burn times....I am focusing on the cat stoves. BK's are definitely where its at.

I have excessive draft so even when shut down with a full load of dry wood the NC30 would burn in the 700's when the secondaries light off. I have to try hard to stay ahead of it.

You seem to be measuring stove top temps. Have you measured flue temps? I'm trying to get max output from the NC30 and I am only able to get the pipe up to about 450 surface temp but didn't measure stove top temp yet.

I also have a BK. Heck, I burned both yesterday. I have the princess which would be more equivalent to the chinook 30. It's a much cooler burning stove, if you want it to be. I installed the BK to minimum rear clearance of 6" and it does not get hot back there. The side shields leave the sides of the BKs cool enough to touch. You've got interior side shields, the stove wall, and then the exterior side shields preventing heat from hitting the sidewalls.

With no hearth requirements you can build a flush hearth so the amount of floorspace consumed by the BKs can be very very small.
 
if each stove is installed at its respective minimum clearances, then your wall will probably achieve the same temperature, in instances where you're running each stove hard. I believe this is the answer to your original question.

Thing is, the non-cat has a belly full of fire where the cat stove has most of its heat on the top plate. Perhaps the hot wall will only be hot in one spot with the cat stove but the whole wall with the non-cat. Also, there is a minimum reasonable side clearance that a manufacturer might try and accomplish. Not certain how the test works, maybe the manufacturer proposes a clearance and the wall temp is tested to be okay or another method would be the clearance is slowly reduced until such time that the wall gets too hot and that distance determines the minimum.
 
You seem to be measuring stove top temps. Have you measured flue temps? I'm trying to get max output from the NC30 and I am only able to get the pipe up to about 450 surface temp but didn't measure stove top temp yet.

I also have a BK. Heck, I burned both yesterday. I have the princess which would be more equivalent to the chinook 30. It's a much cooler burning stove, if you want it to be. I installed the BK to minimum rear clearance of 6" and it does not get hot back there. The side shields leave the sides of the BKs cool enough to touch. You've got interior side shields, the stove wall, and then the exterior side shields preventing heat from hitting the sidewalls.

With no hearth requirements you can build a flush hearth so the amount of floorspace consumed by the BKs can be very very small.

Thank you....that is what I was hoping to hear! I had a feeling that on the BK most of the heat exited through the glass and the top.

On the flue temp...I have double wall stove pipe and as I understand it the magnetic ones don't work with double wall, only single wall due to the air space in between the pipe walls acting as an insulator.

I have a probe type that is inserted 18" up into the stove pipe. I forget the exact dimensions, its wherever Condar told me to put it. Generally, the flue and stove top rise and fall at the same time. On a full fresh reload of seasoned wood when the secondaries light off the stove top can be around 800. The flue can read as high as 1100.

Once when it was -5 out and windy I had a stonger than usual draft. With the air fully shut the secondaries were in nuclear mode. The stove top was 850 and the flue read 1250. The fan was on high......as was the pucker factor.

I usually use the flue thermometer more than the stove top. I try to reduce the air as much as possible but keep the flue at 500+ for a clean burn.
 
Thank you....that is what I was hoping to hear! I had a feeling that on the BK most of the heat exited through the glass and the top.

On the flue temp...I have double wall stove pipe and as I understand it the magnetic ones don't work with double wall, only single wall due to the air space in between the pipe walls acting as an insulator.

I have a probe type that is inserted 18" up into the stove pipe. I forget the exact dimensions, its wherever Condar told me to put it. Generally, the flue and stove top rise and fall at the same time. On a full fresh reload of seasoned wood when the secondaries light off the stove top can be around 800. The flue can read as high as 1100.

Once when it was -5 out and windy I had a stonger than usual draft. With the air fully shut the secondaries were in nuclear mode. The stove top was 850 and the flue read 1250. The fan was on high......as was the pucker factor.

I usually use the flue thermometer more than the stove top. I try to reduce the air as much as possible but keep the flue at 500+ for a clean burn.

Great info, particularly that I can monitor pipe temp and so long as I keep internal temps under 1000 I should not expect to overfire the stove.
 
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