Draft

[zmak]

Currently have a englander nc 30. Installed through the wall, stove pipe comes up approximately 3 feet to a 90 degree bend which slopes slightly upwards to the wall kit. There is another 90 degree bend outside and then 6 inch triple wall stainless approximately 18 feet to and past the roof. How will these 2 90s affect draft?

 

[bholler]

They will hurt draft but at 18' you will probably be ok. Is the 90 outside a tee?

 

[double-d]

If you can change the one of the 90 deg elbows into 2 45 degree elbows with a section of pipe in-between, that will keep the gases going upward. I believe that 2 90's are acceptable, anything more will reduce the draft by about 10%

 

[kennyp2339]

I would first run the stove with the 90's as is, once the temps drop into the 20's at night see what the stove does, if is consistently has smoke roll out when the door is open and the stove is running in the 500 deg range, then change the inside 90 to (2) 45's, if you don't get smoke roll out (when its cold outside) then leave as is.
Sometimes having a little restriction gives a better burn. There have been some cases that members here had to much draft and had to figure out how to partially block the stove intake to slow the burn down some, I guess see what you have going first.
I'm saying make the decision to change out the 90 after it gets cold out because draft improves tremendously when the inside house temp is warm and the outside temp is cold, if the out door temp is in the 40's (even upper 30's in some cases) it can give a false weak draft reading when the stove is running. Just my 2 cents.

 

[begreen]

There are multiple factors that affect draft besides pipe height. Outside temps, atmospheric pressure, chimney location, house tightness can also affect draft. If the installation is on the first floor and an average house it may be fine and is worth trying to see how it performs. If this is a basement install then the potential for negative pressure exists and fine tuning the system may be necessary for mild weather burning.

As a test build a small kindling fire with 50F outside temps and see how it performs.

 

[zmak]

They will hurt draft but at 18' you will probably be ok. Is the 90 outside a tee?

Yes, the 90 is the outside tee, I went and measured the chimney myself and found it to be 15 feet from the tee to 3 foot past the roof where the rain caps ends. The remaining measurements are the same with single wall pipe coming off the stove three foot to the 90 then slightly angles upward to the wall kit. Adding the stove pipe and chimney together gives me 18 feet of black pipe and chimney combined.

 

[zmak]

Thanks for the replies! New to burning and if I could and wife would allow I would burn non stop. I do tend to convince myself its cold enough to get a fire going when its probably not needed.

 

[bholler]

Yes, the 90 is the outside tee, I went and measured the chimney myself and found it to be 15 feet from the tee to 3 foot past the roof where the rain caps ends. The remaining measurements are the same with single wall pipe coming off the stove three foot to the 90 then slightly angles upward to the wall kit. Adding the stove pipe and chimney together gives me 18 feet of black pipe and chimney combined.

You may be just fine run it for a while and if it works good great if not change out the 90 inside for 2 45s. if you still need more draft add a few feet to the top of the chimney.

 

[begreen]

If you do need to change the interior pipe configuration, consider switching to double-wall stove pipe using 45s with an offset. That will help keep flue gases hotter which can help draft.

Is this a main floor installation or basement?