two 45 degree elbows instead of a 90 degree?

[Newguy777]

Just got my NC30 wood stove. I am running it through a concrete block wall in my basement. Initially I planned on going straight up for about 3 ft to a 90 elbow, then continue for about 4 ft of Horizontal run (with a slight incline of course) and running eventually into the outside double insulated Stainless Steel Tee, and doing another 90 at the Tee to continue to the roof. The black stove pipe I am using inside the house is Selkirk DSP if that matters.
So heres my question. Wood I benefit significantly by using two 45 degree stove pipe elbows instead of the first 90 elbow I described. This would reduce the amount of horizontal run I have to about 2.5 to 3.0 ft. With this scenario most of the horizontal run would now consist mainly of double insulated stainless steel chimney.
Hopefully the combination of Double Insulated Pipe and DSP will keep things warm and improve draft.

thanks

 

[RSNovi]

(broken image removed)

Here is my setup. It drafts good with 30' of chimney on the outside.

 

[bholler]

I would use 45s personally but with 30' you will probably be ok if you really don't like the look of the 45s. But as long as you have proper clearance i would move the stove over and get it allot closer to center on that chimney

 

[CenterTree]

I would use 45s personally but with 30' you will probably be ok if you really don't like the look of the 45s. But as long as you have proper clearance i would move the stove over and get it allot closer to center on that chimney

This thread started out a little confusing for me. I thought the first and second post was from the same person until I reread it.
I couldn't understand why the OP was asking about his 30NC stove and then posted a PIC of his Jotul.

 

[fossil]

Yeah, the installation pic in post #2 is NOT the OP's stove. A pic of the OP's stove would certainly help. In general, the more changes in direction, and the more abrupt those changes in the flue gas flow path, the more opportunity for the gasses to cool and the condensation/deposition of creosote. The increased complexity of the gas path also complicates effective cleaning. Two 45°s instead of a 90°, coupled with a shorter horizontal run is a good thing. Rick

 

[Newguy777]

Yeah, the installation pic in post #2 is NOT the OP's stove. A pic of the OP's stove would certainly help. In general, the more changes in direction, and the more abrupt those changes in the flue gas flow path, the more opportunity for the gasses to cool and the condensation/deposition of creosote. The increased complexity of the gas path also complicates effective cleaning. Two 45°s instead of a 90°, coupled with a shorter horizontal run is a good thing. Rick

To answer, I am the guy that posted the thread, not the guy with the 30' tall chimney and the pic. Consequently my outside vertical chimney will be about 17 or 18 feet

 

[Newguy777]

To answer, I am the guy that posted the thread, not the guy with the 30' tall chimney and the pic. Consequently my outside vertical chimney will be about 17 or 18 feet

Here is a pic. Facing the wood stove, the chimney pipe would go up and out the left wall (The wall with the insulation in it). If I did use two 45s, technically I would come up 1 foot, go into a 45, go diagonally about 30 to 40 inches, go into the second 45, go about 6 inches horizontally and then continue horizontally with a 2 foot section of stainless steel double insulated pipe to the outside tee. From the tee, 17 feet to the roof.

 

[dougand3]

2 x 45* elbows should draft better. And when you go through the wall - have a slight incline outward.

 

[Newguy777]

2 x 45* elbows should draft better. And when you go through the wall - have a slight incline outward.

Actually that leads me to another question. How can you put an incline on any section of horizontal pipe when you are tying into a 90 degree tee or for that matter coming off of a 90 degree elbow. Is there some flex room where the sections tie together?

 

[dougand3]

You may not be able to incline IN the wall thimble - it may sit horizontally. The black stove pipe can incline from elbow to thimble. The black pipe will be cocked slightly downward in the thimble.

 

[Newguy777]

You may not be able to incline IN the wall thimble - it may sit horizontally. The black stove pipe can incline from elbow to thimble. The black pipe will be cocked slightly downward in the thimble.

Design wise, I thought the stainless steel double insulated pipe went from the Tee, through the wall, through the thimble and ended from 3 to 6 inches into the room, then transitions to black stove pipe. Is that wrong?

 

[dougand3]

I don't know. Do you have a pic of yours or is it coming later?

 

[Newguy777]

I don't know. Do you have a pic of yours or is it coming later?

I posted the pic above. Its the one with the open walls

 

[dougand3]

I meant a thimble/stainless pipe pic. But if black pipe travels only 6" from top elbow to the thimble - an incline won't matter. We're talking of only a 1/4" per foot of horizontal travel anyway.

 

[Newguy777]

I meant a thimble/stainless pipe pic. But if black pipe travels only 6" from top elbow to the thimble - an incline won't matter. We're talking of only a 1/4" per foot of horizontal travel anyway.

I looked at the thimble and it is made for a 8 inch (outside diameter) double insulated pipe. Because of the thickness of my block wall, studded interior wall, etc. I will be using a 24 inch section of stainless steel double insulated pipe. So technically I would have needed .5 inch of fall. Guess there isn't much I can do about this ?

 

[RSNovi]

Sorry. for the confusion. I was just trying to provide an example that works ok with 90s.

 

[Newguy777]

Sorry. for the confusion. I was just trying to provide an example that works ok with 90s.

No, its fine. I really appreciated everyone's help here. I am new to owning and installing wood stoves. There is so much to know! thanks again.

 

[dougand3]

Yeah, I wouldn't worry about the 0.5" incline.

 

[Rossco]

I have two 45* with 12" inbetween and still retain 3' of stove rise.

It's ok to use 45*s but you will reduce the initial rise from the heater.