Equinox elbow or straight up?

[gonefishin]

Do you find any difference in effeciency of the wood stove or problems if the pipe from the stove goes straight up through the roof or if it comes from the back or top and runs horizontally then bends upwards?

 

[begreen]

It depends somewhat on the stove and how tall the flue is (strength of draft). If the stove is shallow (like a Jotul F400) and flue height is not tall, then straight up can make a big difference vs rear exit with an elbow.

 

[RNLA]

There is a rule of thumb about the amount of restriction the elbows add to the pipe ( so many 90's is a certain amount of flow restriction, and so on with 45's or what ever is not a straight section ). This rule is also affected by the amount of horizontal travel. Sorry to be indirect but I do not know the math involved...

 

[fossil]

The straighter up the better. Rick

 

[gonefishin]

I will be more specific this time, I'm still looking at the Equinox stove. how much will efficiency change if I have an elbow with a short horizontal run, maybe 2 feet less, compared to straight up. If I have an elbow j can shorten height of outside like on roof as it doesn't have to go through second floor.

 

[Fsappo]

If you use 2 45 degree elbows with a 45 degree angled run of pipe in between, you'll hardly notice a difference in draft. 2-90s and a horizontal run to move a pipe closer to the peak is a bad idea, especially with a big thumper like the EQ.

 

[shawneyboy]

Common wisdom says straight up is always better. So many factors from total height to length of Horizontal and all. I personally have 2 1/2 up then 90 (Know i should use 2 45's) then 2 foot horizontal, then cleanout T (outside) then up. I have no issues.

Shawn

 

[begreen]

I'm not following. What exactly are the two plans and what are the length of the runs? If you can go straight up, inside the house, the pipe will stay warmer. This will benefit draft and will keep the flue gases hotter, which can mean less creosote condensation and an easier to clean pipe. Also, it usually is less expensive parts-wise, something to think of with expensive 8" pipe fittings. Add the elimination of the 90's and it is the way to go.

(merged threads)

 

[Fsappo]

BG, I took it as he wants to put a pipe thru the roof, but instead of the low end of the roof where there will be more class A outside, he wants to use elbows to move the pipe further up towards the peak. More interior pipe less class A exposed. If its only a matter of a few feet offset, I'd feel fine doing it with 45s instead of 90's. Double 90's with a 2-3 foot horizontal on a single story install/equinox would create a couple of obvious problems. 2-45's...I have 6 wood stoves in my showrooms set up that way, never an issue.

 

[Highbeam]

None of this will do anything for the efficiency of the stove. What it may do is affect your draft, and be cheaper or easier to install. Stove efficiency is pretty constant so long as you meet the stove specs for the flue system.

I am a big fan of a 100% vertical flue when possible. I built mine this way and it allows me to run a stove brush from the roof right into the firebox.

 

[gonefishin]

thank you, that is the information I was looking for. I can run a straight flue from first floor to second floor then out to the roof. If I use a bend in the flue and go through a wall, I can avoid the second floor alltogether and go straight out to the roof from the first floor,saving distance inside approx 8 feet. However Im not sure how high above the roof the flue must extend. This seems cheaper and would not have to mess with upstairs but now I have at least one elbow in the flue.

How would you handle this: vent the flue right from the back of the stove horizontally approx 2-4 feet then bend up to roof or go from the top maybe 5-8 feet vertical then bent horizontal 2-3 feet through a wall then bend back up again through the roof?

 

[begreen]

The height of the chimney cap above the roof depends on the pitch of the roof. The flue needs to be at least 3ft above the roof and it must be 2 ft higher than the any roofline within 10ft. Note that chimneys on the low end of the roof often perform poorer. And they often have to be really tall, with bracing, to meet the 10-3-2 rule.

Bottom line - If at all possible, go straight up, you will be glad you did.

reading material:

http://woodheat.org/all-about-chimneys.html
https://www.hearth.com/econtent/index.php/articles/htchimneyup_twostory

 

[gonefishin]

Wow, great information , I make a lot of sense and I see now what you're talking about .
straight up is better !