Flue damper, what's it for?

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How warm are your rooms and how warm are you expecting them to be? I saw mid-70s earlier for the stove room, what about the others?

I’d also go around with the IR gun to each room and find the cold spots. That might reveal something as well. Check along the walls at the floor, ceiling and windows. Also any penetrations in the ceiling.
Well, its like 32 degrees. The stove room is 68. The living room is 64, spare bedroom is closed office is 62 and me is 63. When it was 0* those rooms were in the 50s. Maybe my expectations are to high
 
Here's a shot up the chimney

Someone help me out here - what am I seeing.

It looks like flex pipe, elbowing 90° into the chimney? Is that right?

If so - what is (or isn't) above that?

This has been a most interesting thread - I have to think there is a lot of heat going straight up here. But not really sure what's 'up there'. Can you get a temp reading on some other surfaces in this space? Like, the one at the very top?
 
I wouldn’t say so. My insert will heat the 450 sq ft of my basement to 83 if I let it and keep the main living area around 70-71.

Did you find any abnormally cold spots relative to their temperature in the rooms?
Not really, i went around the window frames with the ir and all temps were within a few degrees of the room
 
Someone help me out here - what am I seeing.

It looks like flex pipe, elbowing 90° into the chimney? Is that right?

If so - what is (or isn't) above that?

This has been a most interesting thread - I have to think there is a lot of heat going straight up here. But not really sure what's 'up there'. Can you get a temp reading on some other surfaces in this space? Like, the one at the very top?
Its not 90*, its a very soft angle up, maybe in the 140s? What your seeing is a concrete cap at the top of the chimney where it was blocked off by previous home owner.
 
Got it, just trying to figure out how you use it and rule things out.

What's the typical duration that you leave it not burning on any given day?

Going through these sets of questions as it can take significant time to heat an entire home from one spot, then it takes a lot of energy to maintain. Just as an example, we left during the holiday week when temps were single digits or below 0. Set the heat to 64 while we were gone. Once we got back, it took 2 or 3 days to thaw out the house and get it to maintain temps where we normally keep them and even then it was a struggle as the temps remained in the single digits or below. If this insert is your main heat source, it'll take awhile to get everything warm and then very little downtime to keep it that way. As this week warms up through about tomorrow, get the house warmed up while you can and let's see what happens come the weekend when temps dip back down.
 
Its not 90*, its a very soft angle up, maybe in the 140s? What your seeing is a concrete cap at the top of the chimney where it was blocked off by previous home owner.

And on the other side of the concrete - is that cold attic space?

Seems to me this is most of the problem - but nobody else seems to have picked up on it so maybe I'm off base. Looks like a big old heavy duty heat sink to me - not even considering what kind of stack effect might be happening if there are any spaces for air to move through it.
 
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Got it, just trying to figure out how you use it and rule things out.

What's the typical duration that you leave it not burning on any given day?

Going through these sets of questions as it can take significant time to heat an entire home from one spot, then it takes a lot of energy to maintain. Just as an example, we left during the holiday week when temps were single digits or below 0. Set the heat to 64 while we were gone. Once we got back, it took 2 or 3 days to thaw out the house and get it to maintain temps where we normally keep them and even then it was a struggle as the temps remained in the single digits or below. If this insert is your main heat source, it'll take awhile to get everything warm and then very little downtime to keep it that way. As this week warms up through about tomorrow, get the house warmed up while you can and let's see what happens come the weekend when temps dip back down.
I work 12-9 and she works 8-5, so the 4 hour time frame were not home ot goes unattended, and I'll load it at night around 2am before i go to bed.
 
And on the other side of the concrete - is that cold attic space?

Seems to me this is most of the problem - but nobody else seems to have picked up on it so maybe I'm off base. Looks like a big old heavy duty heat sink to me - not even considering what kind of stack effect might be happening if there are any spaces for air to move through it.
The other side of that is the outside world for 4 feet, then it passes through the sauffit, then outside again
 

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Hmm, I wonder how thick that masonry really is, any ideas?

Grab some temps with your IR gun on the outside masonry and contrast them against the wall to the left.
That outside masonary is what you call a facade or veneer I think? The masonary chimney is behind that granotr exterior. I will check temps
 
Your probably losing a ton of heat up that butchered up masonry fireplace. There really cant be any other explanation.
Eliminate the impossible and whatever is left, however improbable, must be the truth. (lets see who knows where that came from).
But seriously....its burning. So assuming your moisture content is correct, and you are actually loading the stove up, that means is it producing heat.
Are you coming home to a stove full of ash or partially burnt logs? I tried to read through it all so correct me if I am wrong.
If you are coming home to a stove full of ash, then the wood is not the problem. That means your keeping the stove too far turned up for too long.
If that's the case and your house is still cold, then the only possible explanation is heat is disappearing somewhere.
 
Your probably losing a ton of heat up that butchered up masonry fireplace. There really cant be any other explanation.
Eliminate the impossible and whatever is left, however improbable, must be the truth. (lets see who knows where that came from).
But seriously....its burning. So assuming your moisture content is correct, and you are actually loading the stove up, that means is it producing heat.
Are you coming home to a stove full of ash or partially burnt logs? I tried to read through it all so correct me if I am wrong.
If you are coming home to a stove full of ash, then the wood is not the problem. That means your keeping the stove too far turned up for too long.
If that's the case and your house is still cold, then the only possible explanation is heat is disappearing somewhere.
Mmm when i get home, she's been feeding it wood. When i wake up in the morning theres usually a few wood caracses left that are coals once I break them up. Ill see about putting in a block off plate this weekend and insulation
 
Your outside temps will confirm the suspicion, but I suspect that you're heating the outside. Block off plate would probably help immensely in your case and is a non-issue to do. As for insulating around the insert, check your gaps to the fireplace and best practice is to contact the manufacturer to ensure they're ok with insulating around it. They may tell you to maintain a specific air gap, which will then determine materials to use in the fireplace.
 
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A couple layers of Roxul stuffed between the liner and flue to sit on the sheet metal. Typically it's screwed in but you could silicone it in place with some high temp stuff I suppose.

As for around the insert, Roxul again if it can be used while maintaining any air gaps prescribed by the manufacturer. The concern here is whether insulation too close will make the insert too hot under normal conditions, essentially overfiring the unit. If Roxul can't be used, some board materials such as Micore or Durock that are used to build hearth pads can be put along the fireplace walls. Micore is significantly better for insulation applications.
 
This here is a picture of my current living room situation. Above my stove is Roxul insulation stuffed up into the fireplace. You can see some of it hanging down. This stuff is rated for 2550 degrees F before it can combust. Needless to say if it was being exposed to that temp, my house is probably already burning down.
Also, my fireplace chimney is capped at the top. Heat has a long way to go to get to my bedroom.it has to goes out of the living room, around the corner, up the stairs and then into my room(Cape Cod house). I consider this an ideal condition because the living room will be 75-80 but the bedroom is still mid 60's which is good for sleeping. Though the furnace has been running a bit in the last month with this severe cold, it usually doesn't run much at all during the 30's or even low 20's. It only runs at night after the stove dies down a bit.


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One possible problem – I noticed in one of the earlier posts that you run the fan on high at all times? I have an insert and almost always run my fan on the lowest setting. I have read that other users do the same. It only takes a little bit of “push” from the fan to move air away from the stove, and the fan tends to cool down the stove when it is turned up too high, certainly if it were on the highest setting. I can get 8-12 hr burns with my stove, but if I always ran it on high, my guess is that I would only get 3-5 hr burns.

It is counterintuitive that turning up the fan reduces the heat you get from a load of wood, but you have to think of it from the standpoint of how the stove is intended to operate. It is most efficient when it operates in a certain temperature range (something like 500-700 for my stove I think), and if the fan is too powerful, it will reduce the stove temp below that range.

At first I wondered why the stove designer would allow the fan to be powerful enough to cool down the stove, which is detrimental to stove efficiency. Why not just limit the speed of the fan to a speed that would not have this effect? I realized though that the ability to cool down the stove is a very useful when the stove gets hotter than you want it to get. Hope this helps!
 
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This here is a picture of my current living room situation. Above my stove is Roxul insulation stuffed up into the fireplace. You can see some of it hanging down. This stuff is rated for 2550 degrees F before it can combust. Needless to say if it was being exposed to that temp, my house is probably already burning down.
Also, my fireplace chimney is capped at the top. Heat has a long way to go to get to my bedroom.it has to goes out of the living room, around the corner, up the stairs and then into my room(Cape Cod house). I consider this an ideal condition because the living room will be 75-80 but the bedroom is still mid 60's which is good for sleeping. Though the furnace has been running a bit in the last month with this severe cold, it usually doesn't run much at all during the 30's or even low 20's. It only runs at night after the stove dies down a bit.


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So i take it the roxul can maintain contact with the liner and be ok? I have plenty of roo. To stuff insulation up there if it can contact the flex pipe.
 
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