I cant figure out what to do so I thought I would pose the problem/question and see what you think. We will have a new stove this year (Ideal Steel) and will totally replace my pipe and chimney but not sure what to do. Currently with the Heritage there is single wall 6" to the ceiling (approx. 5') it then transitions to an 8" air cooled through the roof, or what I think is air cooled. There is an 8" single wall surrounded by a 12" single wall that runs from the ceiling. through the roof about 4'. In total there is approx. 15' of straight run. I thought I had draft issues so I added 3' of 8" 2x wall insulated on to of the air cooled 8". It totally helped the draft issues. so now the real questions. When I replace the chimney what do I do? My local stove store said that a 6" to 8" transition will only help draft, is that true? Should I keep the transition and hope that an insulated 8" will be better than the air cooled set up I have? Do I run 6" insulated from the ceiling up and just add on as needed? Ant thoughts would be appreciated
First, an air cooled chimney can not compare with a good insulated chimney and for sure you'll have to clean them more often. Going from 6" to 8" will usually reduce the draft simply because there is so much more volume in an 8" than a 6". So you have so much volume going up a 6" and then because the space is larger once you go into the 8", the movement must slow which is not the best but sometimes it can work; just not as well. So yes, an 8" insulated will be better than an air cooled chimney simply because it will keep the flue warmer which, if nothing else helps the draft and helps to keep some of the creosote away. Cleaning the chimney is another problem. Two sizes of chimney to contend with when cleaning is not so much fun.
Save some pennies and go with class A from the ceiling support box the rest of the way, 6" insulated will draw a good draft and stay cleaner. the other issue with multiple pipe sizes is cleaning. If you sweep your own chimney or want to learn in the future the transition could be a pain to get through with changing brushes and all. None of its cheap but if it were me id do 6" the whole way unless a stove that NEEDS an 8" chimney like a Blaze King model King is in your plans.
Yep, I'd do new 6" Class A from the new ceiling support box up through the roof. My original stove had a 6" collar and went (with a transition piece) right into 8" single wall. I began with changing out the stove pipe to 6" from the stove to the ceiling, but the biggest improvement came once I finished the whole thing with 6", as the old and new stoves were both designed to use. Start with the suggested minimum height, then add as needed.
In my mind no question, insulated 6 inch is the way to go. Might also go double wall inside as it will keep the gases hotter and there will be less condensate. I was recently surprised to see the difference in quality of insulated chimneys. The best are rated for 30 minutes duration of chimney fire while most are rated for 10 minutes. With you it is likely overkill but peace of mind is priceless. There is some extra cost in going with double wall and premium insulated but for me it is still a no brainer. It'll pull like a freight train and be safer than a Brinks truck. Good Luck!
I went and checked, according to the EXCEL website the Canadian standards for insulated chimneys calls for them to withstand a 30 minute 2100F chimney fire. The ULC code standards (which may apply where you are located) call for 10 minutes of a 2100F chimney fire. The manufacturer I am familiar with is EXCEL and they have a website. Their warranty looks pretty good. I didn't know about any of this when we had our system redone last summer and am not sure what my WETT fellow used on ours. I may call him and ask but its a little late now. There may be a lot more to this than I realize or am conveying but it might be worth checking into. Good Luck Again!
Double wall 6" to the support box, and Class A from there, done like dinner. Thanks for being a guy open to suggestions, and not crying about money. I hate those threads where a guy builds a house, then wants to skimp on his stove/chimney pipe. I got a piece of 8" single, a coat hanger, some tin foil and a 4 screws....is this good enough? You don't buy a Ferrari and then get tires only rated for 110 mph.
I think we all have. Funny thing ive noticed. Those kind of OPs come and aske their questions and then are never found again. Makes me wonder if they realize they cant afford to do it right so they give up the idea. Im ok with that.
Not crying about money at all....want to do it right, its just that my chimney is a mixed bag of stuff right now and its hard to discern which way to go. Our house also sits in a Creek valley that is about 60' below road surface so pressures/temps vary. Just hard to get a handle on where to go when the baseline is all over the place??!!
Start with a good class a of the minimum length that the stove you choose needs, class A comes in modular legnths, if you need more just snap it apart, add more, and install roof struts for support.... Easy peasy.
