1 90 or 2-45's

spc · By: **spc** On: Thu Nov 22, 2007 4:28 pm

I was reading another post Smoke rolls out load door - any advice?. Will 2-45 degree elbows give me a better draft than 1-90? I have a top vent with about 18" vertical before the 90 & a "T" for the baro & then right to the thimble. Not to much pipe. Thanks.

coaledsweat · By: **coaledsweat** On: Thu Nov 22, 2007 9:43 pm

I subscribe to the least amount theorey. The least amount of pipe, elbows, angles and thimble pipe. If you have a great chimney, it really doesn't matter if you have a few turns. A poor one can make life difficult.

WNY · By: **WNY** On: Fri Nov 23, 2007 8:28 am

I don't think it would affect it that much, I would think the straighter the pipe, the better airflow and draft, also, I read somewhere, that Elbows, TEE, etc.. add "XX" in equivalent pipe length. (ie. 90 Deg. Elbow is equal to 10 feet of straight run? or something like that)

Matthaus · By: **Matthaus** On: Fri Nov 23, 2007 1:39 pm

Actually two 6" 45* Els would have slightly less loss than a single 90* EL. The cost however, does not make this worth it.

Forgot the ratios on the table, they are 1/4, 1/2 and 3/4 going down from the top row for d/D.

1 90 or 2-45's

1 90 or 2-45's

Re: 1 90 or 2-45's

Re: 1 90 or 2-45's

Re: 1 90 or 2-45's