All the heat goes up the chimney myth

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ctyankee

Burning Hunk
Oct 25, 2019
184
connecticut
Three feet from the fire and it is at 126 degrees fahrenheit (127 before I turned it for photo). This is a small fire. I've had the temp gauge there less than 10 minutes. Heat is going up the chimney. But there is a lot of heat to spare. How hot is it 3 feet from your stove?
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Sure, the air there also warms. But then gets sucked into and out of the chimney while it is being replaced by cold air...
 
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Sure, the air there also warms. But then gets sucked into and out of the chimney while it is being replaced by cold air...
So if I OAK it like some stove owners, I'm way ahead of the game. A conduit from a window to the firebox. Well constructed fireplaces are less efficient and take tending to; can't (or shouldn't) go run errands or let the pets wander. Otherwise they can be phenomenal heaters.
 
Three feet from the fire and it is at 126 degrees fahrenheit (127 before I turned it for photo). This is a small fire. I've had the temp gauge there less than 10 minutes. Heat is going up the chimney. But there is a lot of heat to spare. How hot is it 3 feet from your stove?
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The reason temps are that low is the massive ammout of dilution air that goes up the chimney with the exhaust. That makes it extremely difficult to creat any meaningful heat with an open fireplace and often leads to a negative net heat output.


Also if your flue gasses are that low you will have big creosote problems
 
So if I OAK it like some stove owners, I'm way ahead of the game. A conduit from a window to the firebox. Well constructed fireplaces are less efficient and take tending to; can't (or shouldn't) go run errands or let the pets wander. Otherwise they can be phenomenal heaters.
What exactly is your definition of a phenomenal heater. Mine is heating my house comfortably with as little wood as possible and as little work as possible.
 
The reason temps are that low is the massive ammout of dilution air that goes up the chimney with the exhaust. That makes it extremely difficult to creat any meaningful heat with an open fireplace and often leads to a negative net heat output.


Also if your flue gasses are that low you will have big creosote problems
Creosote problems? This chimney is circa 18th C. Still standing. Go try and scare someone else.
 
Creosote problems? This chimney is circa 18th C. Still standing. Go try and scare someone else.
I am not trying to scare anyone just stating the fact that if that is an accurate measurement of your flue gas temp creosote vis going to condense out quickly . That is basic physics.
 
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You honestly think I don't know the condition of this stone chimney? I'm insulted.
The condition of the chimney honestly doesn't matter. Flue gasses have to stay above 220 or creosote condenses
 
I haven't measured that. I've measured 3 feet away from the firebox in the room per the post. I guarantee you it is over 200 up the flue. I've roasted meat at the firebox. 400 degrees maybe higher. I've been in the chimney. Cleaned. Not every inch. It's a Cape. 80% of the chimney is visible from outside (attic). Parged on outside. Rebuilt at the roofline. Etc. FYI, Code is grandfathered in --- this chimney meets code. That's another kinard to make money.
 
I'm very interested in the reply to my point that code is grandfathered in. Much of this "doesn't meet code" stuff is fraudulent.
 
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I haven't measured that. I've measured 3 feet away from the firebox in the room per the post. I guarantee you it is over 200 up the flue. I've roasted meat at the firebox. 400 degrees maybe higher. I've been in the chimney. Cleaned. Not every inch. It's a Cape. 80% of the chimney is visible from outside (attic). Parged on outside. Rebuilt at the roofline. Etc. FYI, Code is grandfathered in --- this chimney meets code. That's another kinard to make money.
Ok I misunderstood I assumed you were messing flue gas temps which is why I said " Also if your flue gasses are that low you will have big creosote problems" . But yes that is pretty good radiant heat off the stove. Now what is your temp in the next room over with all other heat sources turned off all day?

As far as code you are correct you don't have to bring it up to code unless you do extensive work on it. But that doesn't mean it meets code just that you aren't required to bring it up to code.
 
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I'm very interested in the reply to my point that code is grandfathered in. Much of this "doesn't meet code" stuff is fraudulent.
What is fraudulent?
 
By the way I have absolutely no issue if you like using your open fireplace. I know and work for many people who do and that's perfectly fine. But when compared to a stove they simply are not good heaters.
 
As far as the code thing goes just because you don't have to bring it up to code doesn't make it safe. I have not inspected your chimney so there is no way I could possibly speak to it's safety. But many fireplaces and chimneys from that area are very unsafe to use at this point. And many were unsafe from the start.
 
What is fraudulent?
You don't tell people their chimney is legit code wise, "it is grandfatherd in". You say it is not up to code. Period. You and others do not make this important point known. You throw out the phrase "it is not up to code" to scare people into changing things. Period. I can find posts here. I've heard it myself.
 
You don't tell people their chimney is legit code wise, "it is grandfatherd in". You say it is not up to code. Period. You and others do not make this important point known. You throw out the phrase "it is not up to code" to scare people into changing things. Period. I can find posts here. I've heard it myself.
I typically say that in reference to a new stove install or a liner install. And in those cases you are required to bring it up to code. As I said you are not. Now if the firebox ever needed rebuilt at that point you would be.
 
It does meet code! That's the point. That's what "grandfathered" means. The only relevant code is at the time of being built. If you want to say "current code," fine, when trying to scare people. But say CURRENT code.
 
It does meet code! That's the point. That's what "grandfathered" means. The only relevant code is at the time of being built. If you want to say "current code," fine, when trying to scare people. But say CURRENT code.
That is not an accurate statement. Btw I never make any statements to scare people. I am only concerned with keeping people safe. Many times I will say it doesn't meet code but I don't see a safety issue
 
There is a TON of nitpicking on this site. Slammer installs are bad news. But there is a TON of nitpicking.
 
There is a TON of nitpicking on this site. Slammer installs are bad news. But there is a TON of nitpicking.
Yes I agree. And most of that not picking atleast from me comes down to liability and insurance issues concerning installs not so much safety. But when it does come to safety I absolutely will not compromise and won't apologize for that
 
For giggles (and not to make a point either way, because I don' t think it says enough about the situation to make a judgement about efficiency either way), I put a thermometer 3 ft in front of my stove. It died at 120 F... :-(
 
It does meet code! That's the point. That's what "grandfathered" means. The only relevant code is at the time of being built. If you want to say "current code," fine, when trying to scare people. But say CURRENT code.
You are missing the point that when a Insert is installed it is a new installation. It needs to meet current codes because you are changing its use. It is only grandfathered if you continue to use it as it is.
 
You are missing the point that when a Insert is installed it is a new installation. It needs to meet current codes because you are changing its use. It is only grandfathered if you continue to use it as it is.
Yes and just because something is grandfathered in doesn't mean it meets code. Just that you don't need to bring it up to code.