Chimney Height Question

[stoveguy2esw]

hip roof installation on a 2 story is always a troublesome installation. many folks make the mistake of setting the 10-2 based strictly on the roof they penetrate leading to down drafting on a consistent basis , the OP on the other hand has stood a higher flue up , but it still doesn't quite meet 10-2 on the second story roof, this results in an inconsistent draft. wind direction is the variable.

add the extra 2 ft if that will get you closer to the 10-2 for the second story ,or more if needed to get to that balance i'd start without the vacustack , if the chimney to roof height is proper then you wont need it anyway. seeing as the old 18-p from my company was downdrafting with its easy breathing ability , the stack may cause major downdrafting with the napoleon (not putting the "nap" down BTW , its a solid stove, just looking at the higher draft demand from the EPA stove than you are used to with the PRE-EPA Englander) the 10-2 is CRITICAL to get the stove to perform consistently especially with a less than ideal placement (not your fault) and the leaky house. stack effect is a major driver in your downdraft issues but the chimney can overcome it if its placed high enough in relation to the second story roof

 

[SummerTyme]

hip roof installation on a 2 story is always a troublesome installation. many folks make the mistake of setting the 10-2 based strictly on the roof they penetrate leading to down drafting on a consistent basis , the OP on the other hand has stood a higher flue up , but it still doesn't quite meet 10-2 on the second story roof, this results in an inconsistent draft. wind direction is the variable.

add the extra 2 ft if that will get you closer to the 10-2 for the second story ,or more if needed to get to that balance i'd start without the vacustack , if the chimney to roof height is proper then you wont need it anyway. seeing as the old 18-p from my company was downdrafting with its easy breathing ability , the stack may cause major downdrafting with the napoleon (not putting the "nap" down BTW , its a solid stove, just looking at the higher draft demand from the EPA stove than you are used to with the PRE-EPA Englander) the 10-2 is CRITICAL to get the stove to perform consistently especially with a less than ideal placement (not your fault) and the leaky house. stack effect is a major driver in your downdraft issues but the chimney can overcome it if its placed high enough in relation to the second story roof

Thank your for you input Mike. I did love the old Englander stove. It served me well for 15 years and it is still in working order. There are no cracks in the cast iron and the welds are all solid. All it needs is a new window casket, and that is after 15 years of use. The door casket is still tight with no leaks (candle test). I have not parted with the old Englander. I am storing it in one of my out buildings just in case I can't get this new stove to work for me.

If the 10-2 is that critical for these new stoves, then I guess I had better add the 2 feet. And Begreen has told me that the Napoleon needs a 16 foot chimney and right now its only 14 foot. It will make the outside stack 11 foot tall and I do have a concern about the additional lean. Securing the stack at the top is probably going to be even more important as it will be taller. I will probably add more guy wires. Right now I have guy wires that run from approximately the 4 ft level to all four corners (just above the stainless steel section in the pics) and also at the current 9 foot top to all four corners. I will add more at the 11 foot top when I add the additional two foot section. I do get extreme winds out here and I don't want the chimney to topple over. That is my biggest fear with so much stack length. Maybe I'm being paranoid. lol

And to Begreen, I will not do anything to the draft control until I use the stove for awhile and see how it operates. The questions I posed about fiddling with the draft holes was more out of curiosity. My plan is to start with smaller loads which I realize will mean more frequent reloading. (What I mean is putting fewer logs in, not smaller size logs.) As I get comfortable with the smaller loads I will start gradually increasing the amount of wood I load until I can figure out what amount of wood to load for the most efficiency. I plan to experiment with both north/south and east/west loading. My splits are of various sizes from small 2 in to 8 in. I even have some half splits that are probably 10 inches. I don't plan on using the half splits until I really have a handle on this new stove. I used the half splits in the old Englander at night to try to get longer burns.

I appreciate the advise from all of you knowledgeable guys Since I've put this much money into a new stove, I need to get things right so I can be cozy this winter and not be stressing over this new stove..

.

 

[begreen]

You'll find that the smaller splits will have a tendency to flare up quicker. Larger splits tend to burn more steadily. As soon as it gets cold outside I would graduate to those 6-8" splits and fill the gaps with the smaller splits.

 

[stoveguy2esw]

stack height is not as critical as 10-2 you will need that 2 ft. make sure its secure though.

like I said earlier you got dealt a chit sandwich with the hip roof placement. it can be overcome but its 'awkward' as it leaves a lot of stack exposed/ please remind yourself to check the flue system regularly early one until you wrap your head around the burn method of the new unit to ensure you are pulling well enough to keep creosote out of that big ol exposed stack. its different, you get buildup from things that you don't from the old stove.

 

[SummerTyme]

please remind yourself to check the flue system regularly early one until you wrap your head around the burn method of the new unit to ensure you are pulling well enough to keep creosote out of that big ol exposed stack. its different, you get buildup from things that you don't from the old stove.

Mike, when you say "check the flue system" I'm not sure how to do that. Its a straight up chimney and the stove pipe is connected securely. It would mean moving the stove to disconnect the pipe. I watched it being installed and they attached the stove pipe into the chimney by walking the stove under the stove pipe until the pipe was straight up to chimney connection .It is not a telescoping stove pipe, but sections of pipe. It is very snug and there would be no way to take the pipe down without moving the stove or tilting the stove. Its a heavy stove and not something I could move. So then do I have to go on the roof and climb a ladder 11 ft, take the cap off and shine a light down the chimney in the middle of winter?

 

[DanCorcoran]

Here's the bracing on my chimney...rigid. Just so you can picture it.

 

[SummerTyme]

Here's the bracing on my chimney...rigid. Just so you can picture it.View attachment 136354

Hey, thank you for that pic. That does help. Your stack looks fairly long like mine is. Do the rigid braces hold the chimney stable even in high winds? Not having any bracing on that top section below the cap would make me nervous. I probably do overkill with my guy wires, but the winds here can get very high and on occasion we can get straight line winds. I don't want my chimney to crash especially when I'm burning in the winter.

I have a question: Do you have any drafting problems being that close to trees? I like your storm collar - it seems to fit nice and tight. My storm collar sticks out more and sometimes I get snow blowing up under it. I would like a collar that has a steeper angle like yours. Where did you get it?

 

[begreen]

You are required to have a bracing system at every 5 ft of pipe above the roof. As noted earlier, rigid bracing for the bottom section at least would be my preference.

 

[DanCorcoran]

Hey, thank you for that pic. That does help. Your stack looks fairly long like mine is. Do the rigid braces hold the chimney stable even in high winds? Not having any bracing on that top section below the cap would make me nervous. I probably do overkill with my guy wires, but the winds here can get very high and on occasion we can get straight line winds. I don't want my chimney to crash especially when I'm burning in the winter.

I have a question: Do you have any drafting problems being that close to trees? I like your storm collar - it seems to fit nice and tight. My storm collar sticks out more and sometimes I get snow blowing up under it. I would like a collar that has a steeper angle like yours. Where did you get it?

I paid the stove dealer to install the chimney, along with the stove. Because of the metal roof, they also brought along a couple of guys from a roofing company, to do the penetration and sealing. All of the chimney metal is Metalbestos and the roof bracing kit is Selkirk. (There are two sets of braces and I'm pretty certain the top set is within 5 feet of the chimney top).

I've been at the cabin with 55mph winds with no problem. I'm pretty certain there've been stronger winds, as it sits at the very top of a ridge. As to drafting, I've never had a problem...in fact, have started a fire easily with outside temps in the 50s

 

[SummerTyme]

Update:

Today I installed the extra 2 feet of chimney. My stack height is now the recommended 16 ft (from top of stove to top of chimney) for my stove. I am still not 2 ft above my second story, so I left the VacuStack cap on. The lean on the chimney did not get worse. I was able to correct some of the lean with the new guy wires (including turnbuckles). I now have 10 guy wires supporting the chimney. That is a lot of stack to support, but I think it would take a tornado to blow the stack down now.

It was hotter than blazes up there on that roof today. We had temps hit 87 degrees with little wind. I decided to tackle the job today since the winds were going to be light and not blowing the stack around.

Now the next order of business is to fire the stove up when the temps get into the 40's. Probably sometime in October. Then we will see how the chimney works with the stove.

Thank you everyone for all your input.

 

[Woody Stover]

stack height is not as critical as 10-2

Summer, what is the distance from the stack to the second story wall?

Today I installed the extra 2 feet of chimney. My stack height is now the recommended 16 ft (from top of stove to top of chimney) for my stove.

I don't doubt that you did add the 2', but I'd enjoy seeing new pics nevertheless...

 

[SummerTyme]

Summer, what is the distance from the stack to the second story wall?I don't doubt that you did add the 2', but I'd enjoy seeing new pics nevertheless...

Its 11 feet from chimney to second story wall, but probably less to second story roof because of the overhang.

Here's a pic after addition of 2 ft section of chimney.

 

[Woody Stover]

Which way are those heavy winds coming from, across the ridge and toward the stack?

 

[SummerTyme]

Which way are those heavy winds coming from, across the ridge and toward the stack?

Out of the west or southwest towards the stack. Stack is on west side of house. Only time I had issues with old stove back drafting and without the additional 2 ft of chimney was high west or southwest winds above 40 mph.

 

[Woody Stover]

With the additional chimney, you'll have better draft. I think the additional height may also get the top of the stack above the stronger portion of the downdraft. Hard to tell from the ground shot where exactly the top is in relation to the roof...and I'm no wind scientist either.