Calcuating vent pipe length...

[flamegrabber]

They say a Tee or a 90 degree elbow counts as 5 feet, and a 45 degree counts as 3 feet.

Does the clean-out Tee that is directly connected to the back of the stove count as 5 feet too?

Seems like that should not count because it would eat up 5 feet right from the start.

Anyone know?

Thanks,

FG.

 

[imacman]

IMO, I would think the T would count as 5 feet, since the gases have to turn there just like any other 90.

 

[MrJitters]

Correct. Clean out T = 5 Feet.

 

[flamegrabber]

I have the Breckwell Bi E and according to the manual, if you're over 15 feet of vent pipe, go to 4" pipe instead of 3".

If I calculate everything, 2 45's and trhe one 90 clean out tee, p,luss all the straight pipe ( it's a vertical installation ) I'm just under 19 feet.

That's taking into consideration that straight vertical pipe counts 0.5 feet per foot.

You think it will fail inspection for this? Or do you think they'll let it pass.

Thans,

FG.

 

[MrJitters]

I have the Breckwell Bi E and according to the manual, if you're over 15 feet of vent pipe, go to 4" pipe instead of 3".

If I calculate everything, 2 45's and trhe one 90 clean out tee, p,luss all the straight pipe ( it's a vertical installation ) I'm just under 19 feet.

That's taking into consideration that straight vertical pipe counts 0.5 feet per foot.

You think it will fail inspection for this? Or do you think they'll let it pass.

Thans,

FG.

My EVL was just under 19 and i went with 4". First I would consult your owners manual for the stove. Quadrafire gives one of the best charts taking into consideration altitude and length of pipe. Harman, not so good. Not sure about Breckwell. Specifically, I would go with 4" if EVL is over 15 unless your stove manufacturer says otherwise. That way you are covered. Besides, you want the stove to vent properly and 4" will do the job. Remember, free advise is usually worth what you pay for it. %-P

 

[imacman]

.....My EVL was just under 19 and i went with 4". First I would consult your owners manual for the stove. Quadrafire gives one of the best charts taking into consideration altitude and length of pipe. Harman, not so good. Not sure about Breckwell. Specifically, I would go with 4" if EVL is over 15 unless your stove manufacturer says otherwise. That way you are covered. Besides, you want the stove to vent properly and 4" will do the job. Remember, free advise is usually worth what you pay for it. %-P

I agree w/ Mr.J.......go by what the owners manual says. In my town, the inspector wanted a copy of the page of the Astoria manual that shows the install type I was going to use, and he made sure during the inspection that it met that. It did, and I passed w/ flying colors.

I'm sure every town is different, so ask some questions when you apply for the "permit" or whatever they call it there. IMO though, I'd go to 4" ASAP out of the stove.

 

[flamegrabber]

What is the reason for the larger diameter at greater lenghts than 15 feet?

Is it draft, cresote, both, other?

Thanks,

FG.

 

[MrJitters]

What is the reason for the larger diameter at greater lenghts than 15 feet?

Is it draft, cresote, both, other?

Thanks,

FG.

Draft. Too much resistance in the piping will result in an improper draft. Simply put, the larger diameter pipe offers more volume for the smoke to be vented easily.

 

[flashbang]

I ran out the stove 12 inch then 45 bend straight 18 inches to Tee then up 6 feet up with a 90 and jet cap. All 3 inch. The 6 foot up draft makes up for the 4 inch volume.

 

[flamegrabber]

Flashbang,

I have a 90 degree clean out tee at the stove exhaust, then straight up 36" to a 45, then 21" to another 45, then straight up 10 feet to the cap.

How does that sound?

Hpw many 90 degree joints do you have?

Thanks,

FG.

I ran out the stove 12 inch then 45 bend straight 18 inches to Tee then up 6 feet up with a 90 and jet cap. All 3 inch. The 6 foot up draft makes up for the 4 inch volume.

 

[MrJitters]

I ran out the stove 12 inch then 45 bend straight 18 inches to Tee then up 6 feet up with a 90 and jet cap. All 3 inch. The 6 foot up draft makes up for the 4 inch volume.

Identical to my setup, except you have 18 inches after the 45 & I have 12". Not sure what you mean by the 6 foot up draft making up for the 4". :question: If it works for you, that's great.

 

[flashbang]

I ran out the stove 12 inch then 45 bend straight 18 inches to Tee then up 6 feet up with a 90 and jet cap. All 3 inch. The 6 foot up draft makes up for the 4 inch volume.

Identical to my setup, except you have 18 inches after the 45 & I have 12". Not sure what you mean by the 6 foot up draft making up for the 4". :question: If it works for you, that's great.

Ok, Forgot to mention the pipe is icc Excel. There is a formula for length of pipe and elbows before you need to increase the diameter of the pipe. The way I figured it out was that a good draft would be 3 feet above the stove exhaust, I have 6 feet. Reasoning is that extra 3 feet will create more natural updraft (pull) than 3 feet only, hence no need for the extra volume 4 inch pipe.

side note:
My cost was $550. USD for all the pipe and fittings, thimble, etc.
The pipe I used is the best I have seen with no silicone needed. It has a rubber seal in the inner female SS pipe that the male slides into with a positive seal. No rope/o-ring with the 1/8 click and turn, seal it with silicone and hope it won’t leak. This pipe is just stupid crazy expensive to the point that it should be all SS.
Excell is pricey but worth it. Although officially you cannot, I will say that you can cut to fit on the male end to make exactly the length you need, you can’t do that with the others.

 

[MrJitters]

Yup, the Excel is the best no doubt about that.

 

[millerag]

Looking for some opinions.....

Right now i am in the middle of an install (Harmon P38). I have 6" then a 90 and then 13' of strait pipe through the roof. Will 3" work or should i just go with 4"?

 

[sandman460]

13 feet of true vertical length only counts as half - i.e. 13 feet is actually 6.5 feet of effective length.

Using that number, you have 6.5 feet for the vertical, 5 feet for the 90, then 6" for the horizontal, or 12 feet total. I'd use 3" diameter vent, assuming your 13 feet is a TRUE vertical (AND you are below 3000 feet elevation).

 

[Jester]

Ive got 6" out the back and then 90 and up 20 feet or so. The cost wasnt that much more for me to go with the 4", and the chimney guy made the excellent arguement that as the pipe starts to get dirty (if) I wont have to worry as much about it restricting the airflow. If the cost doesnt matter that much, Id say go with the 4, but I overbuild everything anyhoo

 

[hoverfly]

Venting your Pellet Stove

 

[sydney1963]

Mine all adds up to 17 and I am using 3" DV pipe (up inside the house and out) and it burns excellent. Used OAK too.