6"to 8" adaptor?

[fossil]

...I would say it is safe to say that you want neither too small a chimney nor too large of one. Best bet is to use the same size chimney as the flue collar on the stove you are using.

Agreed, 100%. Rick

Furthermore, NFPA 211 agrees with you as well, and goes so far as to quanitfy some of the chimney sizing issues were dancing around here.

 

[fossil]

NFPA 211 says that it is not permissible to exhaust a wood-burning appliance into a flue smaller than the collar on the appliance, so technically speaking, going 6" to 5 1/2" is a no-no...but not a real big one. Exhausting into an exterior masonry chimney, the chimney flue can be up to twice the cross-secional area of the collar, and for an interior chimney up to three times. So, if you exhaust a 6" diameter collared appliance into an 8" diameter flue, you're OK so far as NFPA is concerned, regardless of the chimney location, because you're at 1.78. I'm simply arguing that it might not be optimal, that's all...never said it flat out wouldn't work or that it's unsafe in any way. Rick

 

[perform23]

Since the original poster's question seemed answered and because there is so much good information in this thread...I thought that I would try asking my question here. If it does not get noticed, I guess I'll try a new thread.

Similar to the original poster, I have a potential issue. I have an old Fisher Papa Bear woodstove (I think - See attached Picture) and I have been thinking that I wanted to get a new modern Drolet Sahara EPA stove. There is a Drolet Dealer at one of the big box stores here in Atlantic Canada that carries them, but the kid that I was talking to didn't seem to know much about woodstoves in general.

The new one that I want has a 6" flue collar and the current stove pipe and insert that I have going into my chimney is 7". I do not like the thought of having to shell out even more money to get a new insert installed when the insert that I have is fairly recent. Would 1" really make that big of a difference if I were to put an adaptor on at the flue collar to bring the size up to 7"? Is this typically a fire code or insurability concern?

The interior pipe goes to an outside brick chimney that has a 7" insert in it. The stove that I have now heats 3 levels of my home beautifully, so I want to make sure that I get a good quality replacement. All of the EPA wood stoves that I see around here have a 6" flue collar.

Thanks for the help!

 

[kjsnooks]

I have a question about your to tall chimney post Rick(i dont know hwo to block the text to repost it) An this is just purly bullshiting right now on my part, but wouldnt the fact there is a constant source of heat at the bottom eventually cause the whole chimney to heat up and there fore creating some sort of draft? It could take a long time but as long as the source of heat never goes away the heat would eventually get to the top i would think. And since the heat is the driving engine in the whole shebang could you ever really have to tall of a chimney?

 

[fossil]

I have a question about your to tall chimney post Rick(i dont know hwo to block the text to repost it) An this is just purly bullshiting right now on my part, but wouldnt the fact there is a constant source of heat at the bottom eventually cause the whole chimney to heat up and there fore creating some sort of draft? It could take a long time but as long as the source of heat never goes away the heat would eventually get to the top i would think. And since the heat is the driving engine in the whole shebang could you ever really have to tall of a chimney?

If the chimney were perfectly insulated so the flue gases lost no heat out the perimeter of the chimney as they rose up, then yes, there'd be no chimney too tall. But that's not the case in the real world...the flue gases cool even as they rise in the flue. Rick

 

[fossil]

...The new one that I want has a 6" flue collar and the current stove pipe and insert that I have going into my chimney is 7". I do not like the thought of having to shell out even more money to get a new insert installed when the insert that I have is fairly recent. Would 1" really make that big of a difference if I were to put an adaptor on at the flue collar to bring the size up to 7"? Is this typically a fire code or insurability concern?

It's neither a code issue nor an insurability issue, it's a performance issue. I don't think that going from 6" to 7" would be a problem. Rick

 

[perform23]

Thanks for the quick reply! I really like the look of the Drolet Sahara, so I am happy to hear that it should not be too big of a deal. I don't usually have a problem with creosote or draft and I am thinking that replacing my 28 year old stove will make thinks even more efficient. I only have a cord or so left of hardwood from last year, and the rest of my fuel is those new briquettes which claim to work as well as wood without the creosote build-up anyway.

 

[gweldgen]

I had a similar situation 2 years ago when we replaced a Bullard Falcon 8 inch outlet with a Regency Medium having a 6 inch outlet. The recommendation from the selling store -Williamson Hardware -was to put the adapter at the ceiling. ( I am using insulated SS chimney straight up) This allowed the stove to keep the flue gasses hotter and compressed for the 4 - 5 ft of single wall pipe. Absolutely no problems with draft or creosote . In fact we did not even have the intermittant backpuffing on real windy days that we had before with the Bullard. Of course the Regency burns everything up much better before it even leaves the firebox.
This information was also confirmed as correct by Copperfield - my supplier of pipe and sweeping tools.

 

[Hanko]

Thanks for the quick reply! I really like the look of the Drolet Sahara, so I am happy to hear that it should not be too big of a deal. I don't usually have a problem with creosote or draft and I am thinking that replacing my 28 year old stove will make thinks even more efficient. I only have a cord or so left of hardwood from last year, and the rest of my fuel is those new briquettes which claim to work as well as wood without the creosote build-up anyway.

check out the photo of my 13 NC install. its in 13NC what the H for. second 6 inch stove on this 8 inch chimney.