Flue damper, what's it for?

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FR9Ford said:
Alrighty, thanks :)
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On one of my stoves I noticed poor draft. I checked the Class A chimney and it was a foot below the roof top (I was a newbie). I added a section of 4 feet and oh what a difference. Stove performs so much better. Recommendation (on this site) is to have the pipe 4 feet above the highest point on the roof.
 
Jan Pijpelink said:
On one of my stoves I noticed poor draft. I checked the Class A chimney and it was a foot below the roof top (I was a newbie). I added a section of 4 feet and oh what a difference. Stove performs so much better.
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So, roxul insulation, block off plate, roxul board and chimney. Whew I gots me a project this saturday
 
Here is the rule for chimney height relative to the roof.

[Hearth.com] Flue damper, what's it for?

Roxul batt insulation is fine, it doesn't need to be Roxul board. Note webby's installation for reference.
 
Just to be clear, the code is not for the chimney to be x # of feet above the highest peak of the roof. This image shows the height requirement.

This is not a draft issue. It is a heat loss issue. Imagine how warm that masonry gets after 4 hours of run time. I bet 2 hours is not enough for everything to equalize. It probably gets another 5 or 10 degrees warmer. That is a huge thermal mass sucking the heat out of the back of the stove.
 

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HomeinPA said:
WAIT A MINUTE.... You're outside....you have a stone chase around the firebox and they converted to a class A and then went through the roof or overhang??? Did the stuff a flexible stainless liner inside the class A?? Am I missing something here??? Is that a prefab fireplace? Something is amiss here.
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It definitely doesn't look like a prefab.
 
"Technically" it's 2' higher than anything within 10' and 3' through above the roofline on the lower side of the chimney. That's the minimum required by code. There is also the concept of making sure the chimney vents above the thermal envelope of the structure. 4-5 feet above the roof doesn't hurt though
 
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HomeinPA said:
"Technically" it's 2' higher than anything within 10' and 3' through above the roofline on the lower side of the chimney. That's the minimum required by code. There is also the concept of making sure the chimney vents above the thermal envelope of the structure. 4-5 feet above the roof doesn't hurt though
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Then i think technically it's ok?
 
Sprinter said:
Are we starting over? This was discussed many pages ago. At this point, though, I'm just listening.
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Lol, it's burning fine. I insulated the chit out of it, and it's kickin arse. Storm blew in last night and my tarp was in the woods, so my woods a wee wet. But it seems to be burning fine. Cruising about 75* less than normal but burn times are up, the house is actually warm. I think I'm doing good.
 
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FR9Ford said:
Lol, it's burning fine. I insulated the chit out of it, and it's kickin arse. Storm blew in last night and my tarp was in the woods, so my woods a wee wet. But it seems to be burning fine. Cruising about 75* less than normal but burn times are up, the house is actually warm. I think I'm doing good.
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I just read through both of your recent threads. Now I'm exhausted. You finally got your answer, but they sure made you work for it.

The picture that you took up into your chimney tells the whole story. Heat rises, and until you stopped up that giant hole, you just had another chimney that was effectively venting the heat up into the chimney and warming the masonry. This was a simple problem with a simple solution. And, my educated guess is that it is the same problem plagues 90+% of insert installs.

Every "insert is not heating" question should be answered with the block off plate/insulation solution first.
 
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ED 3000 said:
I just read through both of your recent threads. Now I'm exhausted. You finally got your answer, but they sure made you work for it.

The picture that you took up into your chimney tells the whole story. Heat rises, and until you stopped up that giant hole, you just had another chimney that was effectively venting the heat up into the chimney and warming the masonry. This was a simple problem with a simple solution. And, my educated guess is that it is the same problem plagues 90+% of insert installs.

Every "insert is not heating" question should be answered with the block off plate/insulation solution first.
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I learned a lot though. And I had absolutely no clue what I was doing. I eventually would of got mad enough I woulda sold the stove probably lol
 
FR9Ford said:
I learned a lot though. And I had absolutely no clue what I was doing. I eventually would of got mad enough I woulda sold the stove probably lol
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Unfortunately I think you learned a bunch of bad or marginal lessons along the way. Glad you stuck with it, it can be frustrating to sift through it all, and $7k is no small investment. I'm still working through it myself, but at least now I know the problems, just up to me to get em fixed. Stay warm!
 
ED 3000 said:
Unfortunately I think you learned a bunch of bad or marginal lessons along the way. Glad you stuck with it, it can be frustrating to sift through it all, and $7k is no small investment. I'm still working through it myself, but at least now I know the problems, just up to me to get em fixed. Stay warm!
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What do you mean bad lessons?
 
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