Should this work? Need Opinions

[jtp10181]

Here's what this customer has.

Isle Royale Stove

Connector pipe is Simpson DVL. double wall air cooled.
Chimney is Simpson DuraTech Class A, double wall insulation packed.

Vent goes off the stove up about 4', 90 elbow and horizontal about 2' through the wall (outside) into a T
Chimney then goes straight up 26' all exposed outside with the standard cap on top.
About 10' of this is above the roof, it looks like it goes above the peak.

From my experiences here I think this should work fine.

Here is the concern, when the stove is going good and hot and they open the doors to load, they get smoke back into the room. They have a stove top temp guage and run it around 400-600 usually. If they try to open to top loader door they get smoke back. This is a very old house and thus, is not sealed up the greatest. I really doubt there is any sort of pressure issues in the house. When they had the chimney swept the sweep noticed a lot of buildup where the horizontal piece comes off the T. He thought there was air leaking in at this point and cooling off the flue. I took the stuff off the bottom of the T and looked up in there and the horizonal section is not fully engaged on the left side (where the supposed buildup was). I could not feel any gaps but I could see where one side was in further than the other. Is this a legit concern? I am hoping to correct this but I'm not sure what kind of trouble we will run into. Any ideas, thoughts, suggestions, welcome.

This is in Wisconsin, and obviously the problem is from last burn season, they are not using it yet this season.

Before you ask... I have pictures but I don't really want to post them on here. I could share them with someone privatly if you are that interested.

 

[stoveguy2esw]

26 ft is a long ways for an exposed pipe chimney , also im not getting the 10 ft above the roof and it looks like its over the peak. the area pointed out not evenly inserted could be a leak point, even if you do not feel a gap. biggest thing though , they tend to get smoke back when the unit is reloaded, what temp would the firebox be at the reloading time? remember that air cools leaving the fire, and with 26 ft outdoors getting cooled even faster that could create a sluggish draw. is the unit slow to start? from a cold start especially? when new wood is added does it spark up quickly or take a little while to get rolling good? the flue outside may need to be insulated further to help hold more heat. might need a chase. but definately check that potential leak point thoroughly as well, it could be magnifying the problem of a cooling stack.

 

[jtp10181]

I tried so hard to cover all the bases. I forgot to mention that they did tell me it starts up just fine. The problem seems to be when they have a good fire going. This leads them (and me) to think that when its drawing really good its also sucking more air in through that gap and causing colder flue temps. They did have the chimney cleaned as I mentioned and I did not hear of any major creosote buildup. Its basically impossible to get to the cap because its so high, so the sweep did it all from the bottom. From the ground the cap looks good.

Also, about the 10ft thing. Counting the pipe sections above the edge of the roof, there is about 2.5 4' sections, 10ft. I just wanted to point out how high the chimney was. From the ground it also looks like the cap is just above the peak of the roof itself, this I know helps to avoid the stack effect.

 

[elkimmeg]

Vent goes off the stove up about 4’, 90 elbow and horizontal about 2’ through the wall (outside) into a T

IS double wall pipe being used in the wall pass threw? Sounds like an air leak as well just wondering if the tee cap is leaking
what about leaks in section joints. The problem sounds like a pipe totally exposed 26 feet cooling down with a problem of over comming reverse flow

that length exposed and the draft having to make 180 degree change in directions you may never solve the puff back issues Solving leakage may help, but I think it is unfortunately the nature of the beast

Is the pipe 3' above the roof

 

[jtp10181]

It is the Class A going through the wall, which goes to a finish collar and a close clearance adaptor, then into the DVL.

It is 10' above the roof, or are you asking if it is 3' above the peak? I am not sure how high above the peak it is. Hard to tell from the ground.

All the section joints except the one in questions have locking bands on them, FYI. I don't think any other sections are leaking.

 

[stoveguy2esw]

i still think you have a cold chimney inversion , or at least are approaching it. here is a question that may add some insight. normally chimneys will draw better when the outside and inside are widely different, meaning a hot inside and a cold outside actually tends to help draft where similar temps inside and out tend to slow it down, so the question is , do they tend to have more issues when its bitter cold or when its not as cold? i know its a reach , but possibilities are getting slimmer now.

 

[elkimmeg]

does it clear 2/3/10 foot rule second what about trees hills outside interference ALON with stove guy questions does it occure on real windy days if so what direction is the wind comming from? are there any trees that ccan cause redirection and downward flow issues The cresote usually will indicate leakage Is it a Temperature issue is it a feequent oroblem but taking place when experiencing Temperature inversions in the attosphere..


Are they opperating the stove correctly. I have two top loaders I open the damper and supply more air prior to opening the tol lid If I crack it first let it equalize then slowly open the lid

If I forget to open the damper instant smoke spillage. If I open it quickly somethimes I can pull smoke spillage out. Never have a problem if I add air make t sure the damper is open the fire stable and crack the top first then slowly open it

 

[jtp10181]

It meets 2/10/3 rule for sure. Yes there are huge pine trees all over the place. Yes they get a downward wind sometimes from the trees. SOunds like it is a combination of different things. I will try to get that gap fixed and then will have to make a fire with them and see what happens.

Thanks for the dieas and suggestions.