SEALING PIPE JOINTS

[JotulOwner]

I have a Jotul stove with Metalbestos chimney system. I am no expert (only burning 2 years), but I noticed that the double wall stove pipe from the stove to the thimball has a large gap at the stove connection ( I think it is also connected in the wrong direction - male end facing up). There are also leaks at the joints leading to the thimball. I have heard that none of this matters if your system is built correctly, but I filled the larger gap with rope gasket last season and I swear it improved the draft. I remember buying wood from a guy who has burned wood for more that 30 years and I noticed he sealed his pipe joints. I didn't think to ask why at the time, but now I wonder if I should have.

I imagine that, if your stove air intake is restricted when you shut it down and the heat is high in the pipe and stove, cool air will be drawn in through the pipe connections that are not air tight. I'm not sure if I am correct.

Any opinions regarding this would be appreciated.

Thanks
Art

 

[MountainStoveGuy]

leaks do matter. they dilute draft. can you post some photos please? Imagine sucking a nice mixed drink through a straw that has small holes poked in it.

Double wall interior pipe is hard to install wrong. Gaps are almost impossible. You cant connect double wall pipe to a stove backwards very easy.

 

[Wood Heat Stoves]

lets see some pics of this upside down close clearance pipe!!

 

[JotulOwner]

The male end faces up and goes into the thimball. You can see that there is a gap between the female end and the stove. This is mostly the outer wall of the double wall pipe (not perfectly round) and there is a metal sleeve on the inside of the inner wall, but it is hardly air tight. You can see where I put some rope gasket. I haven't had any problems with the system, but, if this isn't right, I want to correct it. BTW, this is dealer installed.

Thanks
Art

 

[Wood Heat Stoves]

so the pic on the left is of the flue collar?
it doesn't look like simpson dvl, selkirk brand close cleasance pipe?
take it apart, and put it back together yourself, that way you are sure its done right
there could be an inner liner that makes a better connection than is evident by the outside...if there wasn't the bolt head would serve no purpose
you wil need to take it apart for cleaning anyways right??(good time to check...)

 

[DAKSY]

How long is the first piece of pipe at the flue collar?
If it's more than 5 - 6", I'm thinkin you should have a stove adapter in there to make a better seal...
It should have a male end which fits into the Castine's flue collar & then makes a positive connection to the first
piece of double wall connector...
JMHO, FWIW...

 

[summit]

That is a selkirk double wall pipe... the crimps ARE heading down what you are seeing is the outer crimp; the outer layer has an upward facing crimp (to seat into the flanged out bottom of the next pipe) but the inner smoke pipe has a downward facing crimp that runs back into the stove. this inner part is what carrys the smoke out, and is the part that you want to have the crimp down on... if they installed it backwards, the pipe would not fit onto your jotul. as far as the connection to the stove, they should have a stove adaptor of some sort, looks like they just flanged to double wall over the outlet... there are double wall adaptors, but also a simple flex connector from a ss liner kit also works to adapt to a double wall pipe.

 

[MountainStoveGuy]

It would seem that you could take the bolts off the castine flue collar, and shove that double wall down further onto the flue collar. We never used stove adapters on Jotus with Simpson duravent.

 

[begreen]

Agreed MSG, the way I recall the Simpson DVL pipe connecting to our F400, there was no adapter needed. But looking in the Selkirk DSP catalog it appears this pipe may need an adapter part #266243. The Selkirk adapter has a 19/32" wider gap between the inner an outer pipe to accommodate the cast iron stove collar.

 

[MountainStoveGuy]

Agreed MSG, the way I recall the Simpson DVL pipe connecting to our F400, there was no adapter needed. But looking in the Selkirk DSP catalog it appears this pipe may need an adapter part #266243. The Selkirk adapter has a 19/32" wider gap between the inner an outer pipe to accommodate the cast iron stove collar.

Cool! but i still would take those bolts out?

 

[begreen]

ive had success with aluminum tape

Not a good use of the product. It is rated about 1200 degrees below the stove pipe temp rating (180 degreesF).

 

[begreen]

Agreed MSG, the way I recall the Simpson DVL pipe connecting to our F400, there was no adapter needed. But looking in the Selkirk DSP catalog it appears this pipe may need an adapter part #266243. The Selkirk adapter has a 19/32" wider gap between the inner an outer pipe to accommodate the cast iron stove collar.

Cool! but i still would take those bolts out?

Yes, the bolts are a bit macho and only attach at two points IIRC.

 

[Wood Heat Stoves]

That is a selkirk double wall pipe... the crimps ARE heading down what you are seeing is the outer crimp; the outer layer has an upward facing crimp (to seat into the flanged out bottom of the next pipe) but the inner smoke pipe has a downward facing crimp that runs back into the stove. this inner part is what carrys the smoke out, and is the part that you want to have the crimp down on... if they installed it backwards, the pipe would not fit onto your jotul. as far as the connection to the stove, they should have a stove adaptor of some sort, looks like they just flanged to double wall over the outlet... there are double wall adaptors, but also a simple flex connector from a ss liner kit also works to adapt to a double wall pipe.

using simpson dvl, sometimes a cc connector will work if you dont have other options at hand

 

[JotulOwner]

Agreed MSG, the way I recall the Simpson DVL pipe connecting to our F400, there was no adapter needed. But looking in the Selkirk DSP catalog it appears this pipe may need an adapter part #266243. The Selkirk adapter has a 19/32" wider gap between the inner an outer pipe to accommodate the cast iron stove collar.

Here is a pic of the adapter with the pipe removed. I have had no problems with the system except that I think I can get better draft if I could seal the joints. It just seems like a sloppy connection, but I guess precision in wood burning systems isn't quite as critical as in, let's say, the space shuttle :smirk:

Thanks to everyone for the information. I now have a little better understanding of the connections. I would still welcome any additional ideas regarding how to seal the space between the pipe and stove a little better. Maybe stove gasket with a little stove cement? It will need replacing after every cleaning, but that's ok.

 

[Wood Heat Stoves]

looks like the proper adapter was used, no need to seal that any beter imho, but
furnace cement will hold up to the heat but will crack with expansion, high temp silicone not high temp enuf, mill pak would be your best bet or gasket tape

 

[summit]

i agree, take out those stupid 10mm self threadin machine screws, and get some 1" long , 1/4" drive self tapping sheet metal screws thru it.. there is no hole thru the connector for the bolt to tap into, thus the pressure fit was pushing it apart at the collar

 

[Wood Heat Stoves]

Although we don't recommend that you vent a wood stove thru a side wall, there are pipe parts that can do this installation. This is especially a concern when this installation is proposed for the downstairs of a two story home. The issue is that you need "draft" for a woodstove to operate and especially to keep smoke and odors out of the home. I have attached some draft related handouts for education on this topic. The draft is strongest when a pipe vents directly thru the roof in the highest portion of the living space, looking at the whole air space as one big bubble of air pressure. When you penetrate the shell in a lower portion of the home the air/smoke wants to come in the home not out. So, although I could easily give you an estimate for the tee system that you are looking for with elbows to go around the eave, or a flashing to go thru the eave, I could never assure you that it would vent the odors when out of operation or have enough draft to pull the smoke out of the stove fast enough for it to burn hot.
quote from http://woodheatstoves.com/index.php?main_page=page&id=30&zenid=d5dfca527747bf6721647d58c51c97c8
these are some of the reasons why your pipe might smoke, not poor connection( based on pics, the connection was proper, and shouldn't need sealing under normal circumstances.
i have installed many, many stoves and never used furnace cement or gasket on the pipe joints....