Best EPA drafting Stove for Masonry Chimney

[MovingOffGrid]

I have searched for days online and spoken with two local dealers at length, trying to discover the best new stove choice for my existing chimney if I do *not* want to install 6" stainless steel liner. The dealers opinions (and/or lack thereof) vary so considerably that I am not confident yet when considering spending $2000 on a new stove. I am now here hoping to glean any insight from those who may have experience venting into a chimney instead of perfectly sized 6" SS pipe.

Some background details:

20 year old Basement entry on slab traditional framed home - R40 in ceiling and R20 walls - double glazed windows.
1200 sq ft main floor down where the wood burner and cold air intake is.
1250 sq ft upstairs vaulted ceiling
Straight up appx 30' central chimney built to code with 6"X10" tile flue

I've had a 20+ year old mid size air tight stove (Cascade Triumph running well but with short burn times and too much pollution) Stove enters chimney via single wall pipe into masonry thimble.

With the vaulted ceilings upstairs, approximately 20' of the 30' chimney is inside the home with the remainder in the attic and above the roof line. Each year I get some glazing in the top 10' of the chimney and I clean and inspect it thoroughly myself and have done so for over 10 years. The wood stove has been backup to hot water Nat Gas hydronic heating system (separate vent in same chimney) in floor down and in registers up, but that is on the verge of changing modestly.

I am looking to buy a new, sturdy EPA stove to A) cut down on pollution B) provide longer burn times and more even heat using less fuel and C) the new stove (or the old stove if I can't find a suitable new stove that will draft well) will also have a custom *external* water jacket placed on it's rear or side end, that will pre-heat my hydronic heating water (yes, it will be professionally done with pressure relief valves, extra storage tank, backup circ pump and all essential overflow protections. It will be external, not internal in the firebox so it should not radically affect the burning)

Drafting has never been an issue with my chimney and my old faithful smallish stove, as long as I use well seasoned wood and get it and the chimney warm before dampening it down, but I 'hear' the new stoves may prove difficult on anything other than pure 6" pipe ad not even sure I can get 6" pipe down my flue if I needed to.

So far I like the two local large size stove choices of Regency 3100 or the Pacific Energy Summit, but not even the dealers are much help with info on their performance on a 6"x10" flue, saying only that if I encountered problems, I would more than likely have to go with a 5 1/2 inch flue liner if things don't work out, but then that could also be an issue as it might be too small - {this is where I started rolling my eyes}!

Does anyone here have any experience running either of these stoves or any new EPA stove for that matter, on an existing 6"X10" vertical chimney?

Is a larger EPA stove better for a larger flue size and higher chimney? I don't want to be roasted out of the house but longer burn time and not having to add wood every 3 hours like my old beater stove, is important to me.

Anyone have experience with EPA stoves on regular chimney flues? Can they work well? Can you dampen them down and still get a good clean burn?

Thanks very much in advance for any and all feedback

 

[bluefrier]

but not even the dealers are much help with info on their performance on a 6"x10" flue, saying only that if I encountered problems, I would more than likely have to go with a 5 1/2 inch flue liner if things don't work out

Welcome to the forum, First thing I would have to agree with the dealers on the "try it out" issue.
Personally, I have read alot of complaints about direct connections (venting in chimney flue) and performance, but have
never heard anyone complaining about a 5 1/2 inch liner (self included). Good luck

 

[uptrapper]

I have a 6.5 x 10.5 clay tile liner with my Harman tl300 and it works great. My chimney is central but about 8' than yours. This is my first year running the stove and I am planning on putting a 6" ss liner in this summer because a couple of my tiles are cracked, but I have no complaints at all with how my stove runs currently. I haven't cleaned the chimney yet but have checked it from the roof 3 times so far, just a very thin layer of creosote so far, doesn't seem to have gotten much worse than when I first checked it, had some trouble learning to burn smoke free when I first got the stove but its easy now. I do have problems getting the AB to run above 30 f, but that's really of little consequence to me because if its above 20 f by the time I get a good coal bed my house is so warm I wouldn't even think of adding more wood. I am new to burning wood but I would guess that if mine works fine other stoves would work fine too, but that is just my speculation.

Mike

 

[stoveguy2esw]

thats a lot of chimney at 30 ft , but its not huge you really arent that far out of cross sectional requirements at 60 sq in. figure a 6 inch round is 28.8 sq inches multiply by 2 for external and by 3 if internal , i think it would be ok especially with a larger box, the PE summit is a heck of a stove though i dont know its drafting charactoristics , maybe hogwildz could comment as he has burned one for a while

 

[Hogwildz]

With the Summit, at 30', you may not have a lack of draft, but cannot guarantee that with the added cross section.
The external jacket...... not sure that will get hot enough, and if it does, you may be robbing heat from the stove thus losing the extended burn time and heat output your seeking.
Remember its a stove, not really made for pre-heating water etc. Not saying it def won't work, but your asking it to do 2 jobs, when it is intended to do 1.
Why not just go with a wood boiler?

 

[MovingOffGrid]

Thanks for the fast feedback and nice welcome!

Bluefrier - is your stove rated for 6" and you are doing fine with 5 1/2"? Does it make any difference the height of the chimney when undersizing a flue?

Uptrapper - that's good to hear - Just had a look at your Harmon stove - very nice! 3 cu ft box seems to be close in size to the Pac Energy Summit. Score one for an existing flue working.

Stoveguy2esw - I'm not sure of the general rule on flue size to chimney height ... is it the higher the chimney the more critical the flue size ...or is it the higher the chimney, the more drafting power and hence more flexible flue size?

Hogwildz - Not sure what you mean by the "added cross section"? Ya, I originally started looking for a complete wood boiler but the wife wants something aesthetically pleasing to replace the existing wood stove and it will be tough to hide a monster boiler anywhere else in the house, and also, I haven't seen a wood boiler under $6,000 that has any 'green' burning capacity. Any links to alternative wood boilers for bargain prices?

Worst case scenario and I have to get a SS flue liner down the road, does squeezing a 6" by making it slightly oval, into my 6x10 flue, cause issues with drafting? I can see how it would cause issues with brushing.

Thanks again ...

 

[Hogwildz]

Thanks for the fast feedback and nice welcome!

Bluefrier - is your stove rated for 6" and you are doing fine with 5 1/2"? Does it make any difference the height of the chimney when undersizing a flue?

Uptrapper - that's good to hear - Just had a look at your Harmon stove - very nice! 3 cu ft box seems to be close in size to the Pac Energy Summit. Score one for an existing flue working.

Stoveguy2esw - I'm not sure of the general rule on flue size to chimney height ... is it the higher the chimney the more critical the flue size ...or is it the higher the chimney, the more drafting power and hence more flexible flue size?

Hogwildz - Ya I originally started looking for a complete wood boiler but the wife wants something aesthetically pleasing to replace the existing wood stove and it will be tough to hide a monster boiler anywhere else in the house, and also, I haven't seen a wood boiler under $6,000 that has any 'green' burning capacity. Any links to alternative wood boilers for bargain prices?

Worst case scenario and I have to get a SS flue liner down the road, does squeezing a 6" by making it slightly oval, into my 6x10 flue, cause issues with drafting? I can see how it would cause issues with brushing.

Thanks again ...

Not trying to bust stones, but is the wifey on board with the water jacket set up hanging on the back?

 

[MovingOffGrid]

lol - good point - I think I can hide the jacket pretty well out of sight, so she will have to be ;-)

 

[Wet1]

I haven't seen a wood boiler under $6,000 that has any 'green' burning capacity. Any links to alternative wood boilers for bargain prices?

Not to get OT, but I too have been looking for something like this and find it a little surprising someone doesn't sell a stove (to the best of my limited knowledge) with provisions for some type of internal or external HX. Something like a hybrid stove/boiler... kind of like the TC unit, but with secondary burning. In fact, a friend is also wondering about this and has been looking for the same thing... so I know there is at least some demand out there for such a product. I'd love to have some type of HX on my stove for a small storage system that could be tied into the central heating system or for preheating DHW.

I guess I can understand the safety/legality issues, but having a pair of relief valves factory installed would certainly go a long way towards making it semi-idiot proof. Even if they didn't want to sell it "ready" to use, just having the provisions installed would be enough to grab my interest.


BTW... MOG, longer flues generally create more draft. Slightly ovalizing the liner would not cause any flow or volume issues. I had to do this with part of my fathers liner and it works great.

 

[MovingOffGrid]

According to my local stove dealer, Regency Stoves (among others) evidently did supply an external bolt on side mounted Water Jacket some time back, but someone somewhere didn't set one up right, a small explosion occured and Water Jackets were removed from the market.

It wouldn't surprise me if there has been a concerted effort by the NatGas and Heating oil industries to remove wood hot water jackets from the entire marketplace. A self sufficient consumer is way too dangerous to bottom lines. wink wink - nudge nudge.

Here in BC, there were major incentives some years back to switch homes over to NatGas appliances. Many populated cities have since banned wood stoves and even though NatGas used to be delivered by our own public utility and western Canada is a significant producer, our entire NatGas utility is now owned by a Texas company .... and we all pay way more $$$$ for it than ever :-(

From my cold dead hands they'll have to pry away my wood stove!

 

[bluefrier]

Bluefrier - is your stove rated for 6" and you are doing fine with 5 1/2"?

[bYes Sir[/b]

Does it make any difference the height of the chimney when undersizing a flue?
Honestly, I don't know but hopefully one of the experts will chime in on this

 

[chipsoflyin]

i have a similar set up, the only difference is my flu is 12x12. i have been burning this set up for 3 years(2-3 cords/year), i clean the black pipe once a season and inspect the masonry flue 3 times a year. in the 3 years i have not had to clean the masonry flue as there has been no noticeable build up within. i think the trick is burning seasoned wood, keep the external black pipe temps between 350-450, try to keep a good secondary burn going and dont dampen down to soon. i have a regency 1000s. i thought about trying to preheat water with this stove and decided against it because the cooler stove temps would have a negative effect on emisions and creosote production. hope this helps

 

[Todd]

I have the same sized flue as you and ended up sticking a 5.5" liner down because the 6" wouldn't fit. The draft is much better than before, maybe too good? I have thought about taking it out and going back to the larger clay tile since my newer stove seems to overdraft at times and I just don't have the smoking problems while reloading with this stove like I did with previous stoves.

 

[Wet1]

Todd,
If you're overdrafting, you might want to consider installing a damper in-line.

 

[MovingOffGrid]

great feedback ... happy I stumbled on this site.

Chipsoflyin ... what stove are you using and how high is your 12x12 chimney?

Todd ... at first glance I see your stove has a catalytic converter. I've heard they are more fussy than non-cat stoves when it comes to flue size. Can anyone confirm this?

As far as an external water jacket extracting too much heat, while I don't yet have any practical experience with this, here is an interesting article claiming their solution (50' coil inside a metal panel smothered in a plaster of paris) only used radiant heat and didn't affect firebox temps.

(broken link removed to http://www.motherearthnews.com/Do-It-Yourself/1984-01-01/Add-Water-Heater-To-Stove.aspx)

 

[savageactor7]

MovingOffGrid our chimney is just like yours tptb that inspected it said no liner was needed. As far as ... 'a good drafting stove' goes I dunno the non cats EPA's are all pretty much the same. If your getting a stove for heat get a 3' fire box...if you just want to smolder wood for log burns I guess any stove will do that well enough.

 

[Todd]

Todd ... at first glance I see your stove has a catalytic converter. I've heard they are more fussy than non-cat stoves when it comes to flue size. Can anyone confirm this?

A lot depends on the stove. The 1st stove I had in this chimney was a small Regency and no liner. The draft seemed fine except when I turned the stove all the way down it would smoulder and the flame would die. The 2nd stove was a Hearthstone Homestead and I got tired of smoke spillage during reloads so I installed liner and it got better. My 3rd stove, Fireview seems to draft too good, and installed a pipe damper to slow her down. This stove has much more air supply and a bypass damper so when I open her up it can really get going quickly and warm up that chimney fast. The old stoves sometimes had to crack the doors or ash pan to get them going.

 

[stoveguy2esw]

Stoveguy2esw - I'm not sure of the general rule on flue size to chimney height ... is it the higher the chimney the more critical the flue size ...or is it the higher the chimney, the more drafting power and hence more flexible flue size?...

both are important height v/s the roofline is critical in any case. the rule of thumb for EPA phase 2 stoves (pretty much anything worth buying these days) is the flue size should not be more than 2 times the square inches than the appliance collar. in other words , the 6X10 you have is 60 square inches a 6 inch round hole (or collar) is 28.86 square inches. having too large a flue "cross section" or square inches of size can cause the stove not to maintain a proper amount of draft and in some cases can not be heated sufficiently to stay in the safe burning range due to the larger surface area of a large flue. a liner brings the stack size down to the same size as the flue openig on the stove which allows for a steadier flow as well as a smaller surface area to keep warm thus holding a better draw. as for height , the farther the exhaust travels from the fire the cooler it gets , so too tall a chimney while in your case i do not think it will be an issue , could be with a larger cross section as the lessened heat left in the exhaust as it nears the top of the flue could possibly allow flue temps to drop too far. this causes sluggish draw and also can lead to creosote formation. which i think is whay hog was talking about having to run the stove a bit hotter to compensate for this heat loss

Worst case scenario and I have to get a SS flue liner down the road, does squeezing a 6" by making it slightly oval, into my 6x10 flue, cause issues with drafting? I can see how it would cause issues with brushing....

as for ovaled flue liners , they exist, a 5.5 liner may do just fine as well, i doubt the stove would notice the difference and the oval liner may be a bit more expensive, plus having to go to an oval to round adapter to connect the stove.

 

[chipsoflyin]

my 12 x 12 is 25-30 ft all but the last 6 are internal, the chimney ends 3 foot above the roof peak. the chimney draws well, i have no smoke spillage and no smoke odor in the house. my regency is comparable to their 1100s, 1.3 cu foot fire box, the secondaries are different , i have a manifold at the upper rear of the firebox, where the new ones have 2 secondary tubes running eastwest under the baffle.

 

[karl]

Why are you so against installing a liner?

 

[annette]

Are you in the warm part of BC, or the cold part? Chimneys draft better in cold weather. Height will make a chimney draft more--provided, I guess, that the cross-section isn't too big, or you get a slow-down and cool-down as Mike described. If your winters are pretty warm, you may need a close-to-properly sized liner to get a good draft. If your winters are really cold, the liner may make your draft too strong, and you'll need a pipe damper. Or, the stove may do fine without a liner.

My BF has a direct-connect into a 2-story plus ~8' external chimney, flue size is approximately 6x10 (I may edit this to give the exact dimensions when I can) and he has no draft issues, and no creosote problem (He cleaned the chimney once after about a year of burning whenever he was home, and the creosote amount was minimal). His stove is little, a Lopi Answer, so it's not the one for you.

My stove operates nicely with very little chimney, although I think I'll add a 3-foot section and see if I prefer that--maybe I won't have to leave the door ajar at start-up, or maybe it will burn damper wood better with a stronger draft. I have a total of 16' of stovepipe and chimney, with one stovepipe offset. That's not a lot of draft, but I can start a fire in 55 degrees without a problem. My stove is made by Country Flame, with a 2.3 ft^3 firebox rated at 65,000 btu/hr. They also make a stove with a firebox of 3.1 ft^3 and 75,000 btu/hr. I don't think the 10-12 hour burn times they claim are possible, but I don't load it up to the max and haven't tried to achieve that. Country Flame is "approved for sale in Canada," if that helps.

 

[MovingOffGrid]

I'm near the Fraser Valley in mountains, so we're about half way between interior weather and coast weather. I'll check out your Country Flame stove further ... thanks Annette.

Karl - Our central brick chimney has always been a very pleasing source of radiant heat for the house. With the wood stove downstairs, the chimney once warm (in Spring and Fall the furnace never comes on), also radiates warmth into the main living area upstairs for hours. I'm guessing putting a liner in the chimney will diminish some of its radiant heat storage capacity in the bricks, and focus the heat downstairs in the wood stove. This may not be a bad thing especially if we gain heat for our hydronic pipes through a water jacket, but the pleasant chimney warmth holds some nostalgic value that I would like to preserve if at all possible.

Goldenearringz - lol - I stand corrected .... "From my HOT dead hands, they’ll have to pry away my wood stove!"

Chipsoflyin - I'm wondering if it is to your advantage running a small stove hot, instead of a large stove dampened down, that makes your system work so well in such as large chimney? You seem to be breaking some of the rules yet succeeding quite nicely.

Stoveguy2esw - thanks for that thorough explanation.

Todd - "A lot depends on the stove" - yes, I think you've pegged it. I need more ratings on how well specific stoves suck wind ;-)
Nice looking stove that Woodstock Fireview - unfortunately our Cdn $ is low again, so I'm trying to shop closer to home for now.

- - -

Recently found this for anyone else who wants some general Chimney details
... "What Makes a Good Chimney"
(broken link removed to http://www.woodstove.com/pages/good_chimney.html)

- - -

Now that you've all helped me better understand chimney/stove relationships, my remaining decision seems to be based on how much individual stoves can 'suck wind' - it seems I definitely want to get one that errs on the side of generous moving air capacity, to have the best shot at using my existing chimney.

Any more specific stove air/wind capacity ideas greatly appreciated. After watching my neighbours Regency in action, I suspect I might have to leave the door open more than I would like with that particular stove.

 

[stoveguy2esw]

(broken link removed to http://www.woodstove.com/pages/good_chimney.html)

that link is great! really lays it out very simply and well, i bookmarked it and emailed it to my work computer. glad you posted it

 

[chipsoflyin]

i would think the hot fire has alot to do with it. i did some reading at woodheat.org and that guy recommends not using a stove pipe thermometer. i think what he's getting at is a clean burn has more to do with how much creosote gets deposited than how fast the air moves through the chimney. is your chimney set up similar to your neighbors? my regency really rages if i leave the door cracked.

 

[MovingOffGrid]

his starting method for his large Regency was lazier than I'm used to. He put in some kindling on paper, closed the door and opened the seemingly minuscule draft (I always have to start my non EPA stove with door cracked open - opening my drafts up full just won't cut it). The fire started decently, then he placed a 1/4 log on the fire and in about 10 minutes throttled down the draft half way. The fire grew gradually but never let it thunder like my old beast can. He has a 6" liner on an appx 22' chimney. He had some soot on the window so I am thinking he maybe should be getting it hotter, faster, before throttling it down.

So my concern is whether or not being able to do this sort of lazy start (which may not be best as his sooty window suggested) is a demonstration of drafting ability on a 6" flue, or something that could work on my chimney also? With my non-epa stove, I *must light fires and leave the door open for a good 15 to 20 minutes in order to get the chimney and stove hot, before even thinking of shutting the door and adjusting down the damper. If I was to use his method on my stove, the fire would die. In the event his ability to start the stove and run it on low demonstrates a better draft with his flue than I could achieve, then I am concerned I may have to keep the door of a similar stove open regularly, in order to just achieve a basic, slow steady burn.

Interesting read at woodstoves.org - thanks