CarbonNeutral said:
By the numbers in that thread it is an ovalized 6 inch that is a no no you cloud have issue with draft it cloud also cause some real somking issues
Sweeping chimney with stove installed. UPDATED with drawings - more an install question now
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By the numbers in that thread it is an ovalized 6 inch that is a no no you cloud have issue with draft it cloud also cause some real somking issues
stoveguy13 said:
Don't understand why - the cross sectional area of the oval solid is exactly the same as a 6" round - they sell that size for situations like mine where a 6" will not fit - am I missing something?
Daryl said:
Because (I think) you are still not cleaning the pipe from the stove through the wall to the T - that one still needs cleaning somehow?
They make a chimney whip that hooks up to your drill with flexible rods that will make the bend at the tee.
because you will most likely slow down the flow of the exhaust when you go from round just like a garden hose if you squeez it.
stoveguy13 said:
There's your compromise though - you can go 6" uninsulated, though I'm guessing even that won't fit, 5.5" - lower cross-section, probably still not insulated, or insulated and full cross-sectional area, but with a different aspect ratio.
I really want it to be insulated, don't want a smaller cross-section, so the oval is a go- no other choice - if I was ovalizing it then there could be concerns, but as it's manufactured that way, I don't think there will be an issue.
if it is not something that you want to do then dont do it but dont be surprised if it does not work well if you want to do thew right thing you cloud contact jotul and see what they think what did your dealer say about it?
The dealers that I have spoken too pretty much just push the liner they sell. They rarely promote insulated liner, they often promote 5.5" as a solution to my small flue. I'm not saying that this won't work, just that I would prefer insulated and a cross-sectional area that matches the stove exit. I am not nearly an expert, but certainly the wealth of knowledge on this forum has led me to these conclusions.
You are right that an equivalent dimensional cross section in rectangular vs. circular is not the same. I guess this is attributable to the increased surface area as you move away from a circular cross-section. It is my belief that you can use the equivalent diameter to compare pressure drop between rectangular and round:
http://www.engineeringtoolbox.com/equivalent-diameter-d_205.html
You can use the built in calculator, but you have to futz the width as my liner is an oblong, not square cornered. Further down the page is the equation for oblong pipes:
de = 1.55 (pi* b^2 / 4 + a b - b^2)^0.625/(pi*b + 2 a - 2 b)^0.25
Substituiting a and b (7.5" and 4.5") gives you a diameter equivalent of 6.05. Of course it's never as simple as that - laminar/turbulent flow etc. but there's no way my addled brain can recall any more of my aerospace degree.
That's my take on it anyway - I figure Simpson got it right and the oval will be fine.
You are right that an equivalent dimensional cross section in rectangular vs. circular is not the same. I guess this is attributable to the increased surface area as you move away from a circular cross-section. It is my belief that you can use the equivalent diameter to compare pressure drop between rectangular and round:
http://www.engineeringtoolbox.com/equivalent-diameter-d_205.html
You can use the built in calculator, but you have to futz the width as my liner is an oblong, not square cornered. Further down the page is the equation for oblong pipes:
de = 1.55 (pi* b^2 / 4 + a b - b^2)^0.625/(pi*b + 2 a - 2 b)^0.25
Substituiting a and b (7.5" and 4.5") gives you a diameter equivalent of 6.05. Of course it's never as simple as that - laminar/turbulent flow etc. but there's no way my addled brain can recall any more of my aerospace degree.
That's my take on it anyway - I figure Simpson got it right and the oval will be fine.
it is not size it is flow that is the problem if you want to try it go ahead if you have a issue the first thing everyone would do is tell you to remove that liner. i ahve seen a build up take palce from the six inch line being ovalized at the damper frame only never mind the full chimney.
stoveguy13 said:
This is an equation involving flow, not size - the flow results from pressure differences - the equation is comparing how an oblong pipe can be compared to an equivalent circular pipe when you look at pressure differences, and inferentially, flow.
I'm not saying your experience or advice is wrong, but equally from the discussions on this board many people ovalize pipe themselves and I have not seen reported issues. Thank you for asking these questions though as it has solidified this in my mind.
I extended my fireplace hearth and put a freestanding stove in front of my existing fireplace box. Permantly sealed up the old ash drop, and put a blockoff plate up in the damper, but left the firebox open. I do however have two black steel freestanding plates I slide in behind the stove to reflect heat out away from the open firebox, and hide the old ugly bricks in there. I piped to a tee, so cleanout is just a matter of opening up the tee behind the stove and letting everything drop into a bag.
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