Insert question probably a dumb one

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mtaccone said:
Why is it that inserts do not have flue dampers?

Good question. Sorry I cannot answer it, as I have wondered myself.

mtaccone said:
Or are they supposed to and I don't know it?

As far as supposed to having them, I would say no. If the manufacturer did not ship the unit with a flue damper, then it is not supposed to have one. I am curious as to what some of the experts have to say on this topic though. Good questions. :-)
 
Because you can not get to the flue, it is in the masonary chimney.
 
burntime said:
Because you can not get to the flue, it is in the masonary chimney.

Is that the only reason? If so, I could easily put one in mine, as I have room and could adjust it via a keyhole in the insert surround.
Would the benefits be worth the effort?
 
Im toying with not using my surround because I like the way it looks as is better so I too would be interested if putting a damper in would make a positive difference.
 
The inserts my Grandpa made had dampers; with air controls on the lower sides. Very good inserts those things were (are). My Country has no damper.
 
Dow N. Jones said:
any overdrafting stove can benefit from a damper.
It's a band-aid fix. Instead you should find why it is overdrafting. Maybe it has too much flue or the wrong size pipe. Anyway, modern stoves are made to work at a set draft created by their design and recommended flue height and diameter. If a pipe damper was to be added it should be barometric (having been pre-set with a draft gauge), not user operable.
 
mtaccone - Well, I was asking the same question (which I believe is not a dumb one at all) five years ago when I got my insert. I have lots of opinions, but little time right now to articulate them. Briefly put, I believe a top damper can be very beneficial. My approach can be found near the end of this thread: https://www.hearth.com/talk/threads/13710/
Regarding the need for a surround (no, it is not required), check out this thread: https://www.hearth.com/talk/threads/23704/
For stove and damper theory from an expert, I reccomend: https://www.hearth.com/econtent/index.php/wiki/why_stoves_overfire_from_too_much_draft/ Now I haven't read that whole article for a while, but, as I remember Mr. Gulland is not a big fan of flue dampers because they are subject to operator error - specifically leaving them shut when opening the stove door results in spilling smoke into the room. Yeah, I admit, I've done that a few times, but overall for me the flue damper was a simple and very helpful addition to my insert setup. I was not concerned with overfiring in the sense of a "runaway" fire, but rather just disspointed that I was burning too much wood too fast and loosing too much heat up the flue. Before the damper I had like a 100 degree stove at the end of the burn cycle; now more like 300. Hope this helps and good luck.
 
Interesting discussion of over firing, EPA compliant stoves, and air supply. Non-user modifiable air supplies are okay if the user has a 15 foot tall chimney. My Vermont Castings FPI 0046 ( I think, was here when I bought the house) was showing signs of severe overfiring when I bought the house. It used to consistently simply drive you out anytime it was lit. Year before last, I pulled it and did some work. Tore it apart and noticed five holes in the back bottom of the insert, with raised edges around them to allow more air into the insert than the controlled source at the front. Bimetallic coil springs on the two shutter doors in the front bottom are the only controllable sources.

I took washers of the right size, and drilled a hole in each one about half the size of the original hole. I then used toggle bolts down through them to secure them in place. For good measure I smoothed on some furnace cement, and then remade the hole I had drilled in that, with a divot made into the cement. Still too much fire, so I tore it back down and put a chunk of rope gasket into two of the five. Good to go...

Should mention that the insert is connected to a stainless liner, 8 inch, inside a chimney that is at least 35 feet tall.

What an old timer told me once was the woodstove is the minimum in the equation of heat. The chimney is the power house of a wood burning appliance. It's the engine that makes the fire burn. Too much engine? Goes too fast. Not enough engine? Goes to slow. Either case is no good. One makes cast iron red and degrade, warp even, and the other makes chimney fires eventually and wastes wood.

I can do anything I want to with the insert now... hold it back, or make it hot enough to burn the soot and crap off the glass in the front of it. Had it cleaned last year and got about two inches of gray/brown dust in the bottom of a five gallon bucket. Out of the 35 foot tall chimney, that rates as nothing.
 
As to the original question, modern wood burning appliances generally are able to control the fire by reducing the amount of air, because they're airtight. No need to reduce draft usually, but sometimes because of design features like EPA compliance, they do need to be throttled back some.

Once I replaced the door gaskets, reverse engineered the secondary air supply, and fixed the connecting adaptor that never fit properly, it was great.
 
Ahh.. Here you are again LeonMSPT. I was trying to look up some info ont he stove since an Administrator is trying to tell me the stove is not a good heater. ANd now I see you've done quite a few modifications to yours. Where do you get the time!

Should I be concerned with the cracks in the back corners of my stove? You say yours was showing signed of over firing when you bought your house. Can you see the pics I posted in the other thread? Check out the bars in front of mine.

Thinking about getting started on tonight's fire with hopes of more heat tonight (but just one working fan). You recommend not running the stove with only one fan?
 
bokehman said:
Dow N. Jones said:
any overdrafting stove can benefit from a damper.
It's a band-aid fix. Instead you should find why it is overdrafting. Maybe it has too much flue or the wrong size pipe. Anyway, modern stoves are made to work at a set draft created by their design and recommended flue height and diameter. If a pipe damper was to be added it should be barometric (having been pre-set with a draft gauge), not user operable.

Access is the issue. FWIW, I've not seen a barometric damper on an insert. But they may exist, have you? Many installations are constrained by the height of the flue. Inserts are going to be put in 1, 2 and 3 story homes. If it's 2+ stories, it's going to draft strongly. Also, temperature is a variable. You could probably get away with a 30 ft most of the time in a mild climate where the temp rarely gets below 30, but in a northern one, draft could be too strong for months.
 
I will be adding a damper this spring. I have major over draft. Problem is with over draft is it sucks to much heat out of the box and the resultant is lots of coals. When outside temps get above 25-30deg stove works perfect. But when it gets below 20 outside I have a hard time retaining enough heat to properly burn up all the coals to ash. A damper will slow the draft but also retain more heat.
 
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