Rear flue exit (Hearthstone Heritage)

[rwilson]

Hello all. I have a chimney related question for all of you experts to ponder...

Problem: I am installing a new wood stove and new metal chimney into a 3-year old house. The stove is a Hearthstone Heritage, and the installation will be done by myself and will be in a corner. I have everything planned out for building the raised-hearth pad, building a partial back stone wall with mantel, and now am planning out the chimney. Because of the amount of space that a corner installation takes, my plans call for the stove to be as closest to the wall as possible (following all clearance requirements). So, the real problem, I measured where the chimney is going to go through-the-roof and it is dead-center on a rafter. I've looked into reframing the rafter (done by an engineer) and that just doesn't seem practical. I also looked at putting a bend in the chimney, but it is extremely expensive and there is not a lot of room in my attic to work with (less then 2ft). So, what do I do?


My best solution (so far): I really see 2 options to get around this issue, but I need some expert advice to insure I'm wont be causing issues down the road with a bad draft or cleaning issues or a chimney fire (2 young kids in the house, not taking any chances here!). Option 1: Put a 45 bend + 18" pipe + 45 bend and feed into ceiling support box. This would bring me ~12" away from my rafter, which would put me directly in the middle of my roof rafters! Now, this could cause an aesthetic issue. Option 2: The Heritage supports a rear-flue exit. So, I could put a 45 bend + 14" pipe + 45 bend right out of the stove and then the rest of the stove pipe would be vertical and feed into the ceiling support box. This would also solve my rafter problem, and I believe would be more aesthetically pleasing. BUT, would this cause draft or cleaning issues? Does anyone have any opinions on which option would be better? Any other options someone can think of?

Thank you experts!

 

[begreen]

I'd go straight up instead of rear exit, for the best stove performance. We were in the same dilemma with our corner install, so I set up the Jotul F400 rear exit for aesthetics. Then I moved up to the T6 which is top exit only, so no choice. I had to put in an offset and it bothered me for all of a day. Now it looks perfectly normal. I never notice it. Do it neatly and be happy.

 

[rwilson]

That looks great. Do you have any other pictures (possibly a wider shot)? Also, what type of pipe did you use? I'm looking at using the Simpson double-wall DVL pipe, but I'm a little concerned bc I can't cut the pipe, and everything will have to line up just right! I have detailed CAD plans, so I can get it to work, just more planning on my end...

Do you have any issues with draft / cleaning / or creosote buildup because of the bend? How do you clean your chimney system? Do you remove the baffle or disconnect the pipe (telescoping pipe)? I'm still confused about how best to clean every year once it is in...

 

[begreen]

That's Simpson DVL. They make short adjuster pipes if you are really stuck. They come in a 6-9" and 12-19" I think. But if necessary I would move the stove out from the wall a little bit and stick with a fixed length. A little more clearance is a good thing.

 

[rwilson]

That a very nice looking stove and installation. Is that wall completely "unprotected"? I've thought about doing an unprotected wall (with proper clearance), but it makes me nervous that over time the combustion point will lower and it may spontaneously ignite.

No matter what, I think I'll do exactly what you have done there. I think it looks just fine. I need to offset my pipe quite-a-bit, so I my connector piece between the 2 45-deg bends will be about 18".

 

[Highbeam]

Don't put any bends in that 2' tall attic. Don't use the rear exit since you already will have a super short chimney and you need all the help you can get. Bends are a draft and maintenance problem.

If I understand your issue, you have ceiling rafters that are flat which don't necessarily line up with the roof rafters which actually attach to the sloped roof. I have the same thing going on since my house was built without the premanufactured trusses. Unless your ceiling and roof trusses are evenly staggered, you should be able to send a vertical 6" chimney pipe vertically between them while maintaining the 2" clearance to the wood. You might not have much choice as to where your ceiling support box goes but try and get it right on top of the stove for a vertical system. Might not be possible, and if not, put your stove in the ideal location and then plan on interior 30 or 45 degree bends in the interior connector pipe to get the system all hooked up.

The only reason I would consider going out the back was if that by doing so, I could eliminate all other bends in the system. Note that your stove might need to be set farther into the room since even double wall pipe needs to be 6" from the wall.

 

[Highbeam]

The required clearances are clearances to combustibles. You don't need to protect the wall. In fact, it could be wood paneling. My heritage sits 10" from a painted sheetrock wall with wooden studs.

It's always bothered me, well sorta, when someone gets all particular about a fancy wall protector with an air gap when this entire system lies outside of the required clearance AND does not reduce the required clearance.

 

[begreen]

The T6 actually runs cooler in back than the F400 it replaced. In both installations I have exceeded the stove maker's minimum clearance specs. So far the hottest temp with the F400 burning for 12 hrs that I measured on the wall with an IR thermometer was 137 degrees. That's quite safe from a pyrolysis standpoint. I haven't been burning the T6 long enough to take a full fire reading, but am sure it will be ok. If you follow the stove manufacturer's specs, you should be fine too.

 

[rwilson]

Highbeam, thanks for all the info. How do you like your Heritage? Hopefully I made a good choice!

What I'll do is a top flue exit with 2 bends just like BeGreen has done. My pipe between the bends will just be longer than his. The pipe will then be vertical and feed into the support box (17" behind the flue exit on the stove). Here's a drawing of how I plan to do this. Note that the distance to the back wall is actually the distance to the corner bc it's a corner install.

One final question... How do you sweep your chimney out and collect all of the buildup? Do you remove the baffle, disconnect the pipe, use a telescoping pipe? I'm curious on how others clean their chimneys as I want to make sure I have a good setup for this.

Thanks

 

[Highbeam]

You could also put the joggle up at the ceiling if you'd like. I've seen them done that way to allow for a stove pipe thermometer. You are pretty close to the point where you could have gone vertical to a cleanout tee behind the stove but without doing the math, I would say that your joggle setup is less restrictive.

On my heritage I have a vertical run straight out the top and 8' more class A to the cap. I remove the baffle board in the stove completely and then from the roof brush the chimney all the way into the firebox. I actually got off the roof and checked to verify that the brush was in the firebox. This method allows all of the dust and mess to be contained inside the stove and lets me keep the stove pipe all assembled. I was also able to clean out the secondary burn chamber which is normally concealed above the baffle. We really really like our heritage.

BG, how well does the brush go through the pair of 45s.

Here's a rear cleanout tee photo. In that case the owner used a hearth mount and liner.

 

[begreen]

Haven't had to brush yet. But in our setup it will probably be easier to just disconnect the telescoping pipe above the top elbow, put a bag at the bottom and brush straight down.

 

[rwilson]

Thank you for all the info! I will also have 8' of class A to the top (yes, that means I will have about 6'+ of chimney sticking out of my roof). Also, I was told that removing the baffle can be hard because they are so fragile and aren't cheap to replace. Do you feel that way, or do you feel like you can remove the baffle (carefully of course) year after year and not have any problems?

Thanks again! I'll be starting a new thread soon with a step-by-step build and installation. I'll post a link back on this thread for anyone interested. I'm sure I'll have more questions along the way.

 

[Highbeam]

Nah! the baffle is about 1/2" thick and quite dense. Yes, you could scratch it with a screwdriver or even maybe break it over your knee but being reasonably gentle with it seems to be a proper approach. My Heritage uses three cotter pins to hold it to the burn tubes but I hear that newer ones use SS wire. I expect to remove it annualy since I am less likely to damage that then I am to create a leak or damage the stove pipe by removing it every year. I feel more likely to damage that baffle during normal log loading, especially when loading for the overnight burn.

One new telescoping piece of stove pipe is about 130$. One new baffle for the heritage is like 60$ or at least it was before the huge price increases on their stoves.

You'll need a roof brace for your chimney and you will need to stand above the chimney to be tall enough to insert the brush.

Did you get the blower and the rear heat shield too? The only drawback to the heritage in my situation is that it has a short burn time. Not short for a stove its size but shorter than I would like. Restarts are easy and it stays hot through the night. I burn softwood in a smallish house so the only way to get a longer burn time is to get a bigger stove which would overheat us. I could get a cat stove for a clean, long, and low burn but I didn't. You'll love that huge window.

 

[rwilson]

For those with DVL pipe, what did you use to connect to the flue on the stove and to connect to the ceiling box? I see an adapter for the flue, but wasn't sure if I needed it or not. I also see an adapter for the ceiling box (close-clearance) adapter, but it's SS (not black). I'm looking at northernexpress.com for my pipe/chimney as it seems to be the cheapest.

 

[Diabel]

This is my set up (bend) & I run a brush through it from the top no problem.

 

[begreen]

For those with DVL pipe, what did you use to connect to the flue on the stove and to connect to the ceiling box? I see an adapter for the flue, but wasn't sure if I needed it or not. I also see an adapter for the ceiling box (close-clearance) adapter, but it's SS (not black). I'm looking at northernexpress.com for my pipe/chimney as it seems to be the cheapest.

The DVL adapter, Simpson part #8674 is SS, but you don't see it at all once the pipe is connected to the ceiling box.

 

[rwilson]

Thanks BG, that makes a lot more sense. I went to Menards this morning to look at what they had to offer, and they have a sale going on for their SuperVent chimney and SuperPipe double-wall stove pipe. The prices are very good, and I could save about $200 if I go with the SuperVent instead of the Simpson. I haven't heard anything "bad" about the SuperVent, so I may go with it bc of the price. The chimney is double-wall, SS with a "lifetime" warranty. Any preferences on SuperVent or Simpson?

 

[begreen]

I've never used SuperVent. Maybe post a separate thread with the question? My preference is somewhat biased towards Simpson, but mostly because of the ease of getting parts locally. It's probably fine, just be sure that you have all the parts needed.