An update pic... and a new question about elbows.

[ecstasy426]

In December 2007, the fine folks here at hearth.com helped me surprise my wife with a new Morso 2110 installed in our house in upstate New York. It has been a total dream, and I thought I'd share a composite picture of the set-up just for fun (we've done some re-arranging since this picture was taken, for safety's sake). Can't thank the locals here enough.

It was such a success that we decided to install a wood stove in the barn as well. I got a deal on a new Pacific Energy Summit, which should do a good job heating a very large, drafty space - and as much as I love cast iron, the steel of the Summit ought to heat up faster. I will be piping out the top of the stove, through the inside of the barn. Obviously, going straight up with the stovepipe chimney would be preferable, but the chimney must emerge out the roof of the barn about six feet to the left of where the stove sits, and there's no way to change it. Another piece of annoying news: the chimney must also exit at the bottom of the roof slope, rather than near the peak. I've already taken my lumps with the 10'-2'-3' rule, meaning it'll be a lot of pipe (over ten feet) going out the top, buttressed by a roof guy.

Here's my question: the chimney will go through two spaces: the first floor, which is about 12 feet to the ceiling, and the second floor, which is another 12-14 feet to where the slope of the roof begins. Where is the best place to put the elbows, so I can achieve the 6-foot offset? Does it matter in terms of draft? I was thinking of putting in a 30-degree elbow near the floor of the second floor and running diagonally for a while, then correcting with another 30-degree elbow before going out the roof. Does that sound okay? Also, I assume 30-degree elbows are better than 45-degree elbows?

Thanks so much!

-ian

 

[LLigetfa]

Stick with 30 degree elbows and put the top elbow as close to the ceiling as practical. That way you will be back to vertical well above the floor. Your chimney manufacturer probably has offset tables that will give you the dimensions.

 

[Highbeam]

Great picture. Consider the cost of offsets and extra length of Class A vs. the cost of offsets and extra length of the chimney pipe between the stove and ceiling. I would also consider that it is better to have the bends down by the stove to minimize accumulation of creosote and also so that when it is time to clean the pipe, you can easily disassemble the connector pipe vs. the class A.

So put them at the bottom and yes, 30 degree bends cause less head loss than 45s.

 

[LLigetfa]

and yes, 30 degree bends cause less head loss than 45s.

I try never to lose my head. %-P

Offsets made with two 30's yeild a 60 degree pipe which will collect less creosote than a 45 degree slope. It's called the angle of repose, meaning that more creosote will slide/roll back down the pipe into the stove, assuming a top venting stove.

You also lose less draft with a pair of 30's than with 45's but given the overall length and much of it being indoors, there should be plenty of draft.

 

[Hogwildz]

Agreed, keep it as close to stove as possible. Will stay warmer less chance of creosote build up, and easier to get to to clean. I'll add that if the rest of the run is straight up from there, you may be able to detach at the elbows and clean from bottom up rather than having to even go on the roof. Someone posted a neat cleaning tool called the Soot Eater I think it was called. May make cleaning from bottom up even easier.

Cool pic btw. Just curious as hard to see in photo...does the second floor section oif piping have 2" clearance to the wall? Are you going to build a chase around it?

 

[Hogwildz]

and yes, 30 degree bends cause less head loss than 45s.

I try never to lose my head. %-P

Offsets made with two 30's yeild a 60 degree pipe which will collect less creosote than a 45 degree slope. It's called the angle of repose, meaning that more creosote will slide/roll back down the pipe into the stove, assuming a top venting stove.

You also lose less draft with a pair of 30's than with 45's but given the overall length and much of it being indoors, there should be plenty of draft.

Not sure how it came about or why, but on Durvent's site, they state 45's are no longer allowed. No clue why, may for the situation you just explained.

 

[LLigetfa]

When I installed a chimney in my former home 15 years ago, I used a pair of 45's to offset the chimney because I couldn't have done it with 30's. 5 years later, I sold that house and built the one I'm in now. Back then, (10 years ago) the same manufacturer no longer offered 45's but since I was designing the house from the ground up, I could use a pair of 30's.

If memory serves, I used ICC chimneys on both installs.

I know from personal experience that a chimney brush with fiberglass rods have no problem going around a pair or 30's. No disassembly required. I think 45's wouldn't be a problem to sweep either but I was working out of town and the wife hired a WETT carded sweep on that one since we wanted the written report as a selling feature.

Oh, and as for the chimney going up the interior, I chased it in using drywall on metal studs and I put vents both top and bottom of the chase. The stack effect in the chase sets up quite the convection and moves a lot of air salvaging heat off the side of the chimney which could otherwise be a burn hazard if touched.

 

[DAKSY]

If memory serves, I used ICC chimneys on both installs.

ICC offers 15* & 30* offsets for their Class A Excel in the US & offers 45* offsets in Canada...
Must have something to do with the exchange rate...
Maybe 30* US = 45* CDN?

 

[ecstasy426]

Good advice from all. I'm using the 30-degree elbows and will post pictures.

The existing install (shown in the picture) is about 6 inches away from the wall, maybe more, on all sides. I'm going to build the chasers after this project.

Sorta academic question, but what would be better for a stovepipe: a 6-foot run at 45-degrees before going straight up, or a 12-foot run at 30-degrees?