efficiency of airtight fireplace doors vs an insert

[Korasdad]

Does anyone have any information on efficiency of airtight fireplace doors vs an insert? Fuel in vs heat out.

Is there any reliable way to calculate such a thing or does the fireplace variables make it impossible?

Country Flame indicates 30k btu from their firedoors. How do they calculate that and how would you find the efficiency?

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This compared to an insert such as the Jotul which lists 65k btu and 71% efficiency.

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Thanks, KorasDad

 

[begreen]

An insert will be much more efficient, maybe twice as much depending on the fireplace + doors. And an insert can have a blower which can really help distribute the heat.

 

[burntime]

Are there really fireplace doors that are sealed? I could be wrong but I thought all have air gaps.

 

[PeteD]

I am still a newb, but I think slapping doors on a non-efficient fireplace is not going to get you much.

You either need an insert, a stove, or an energy efficient fireplace (assuming that you do not have masonry now, but rather pre-fab).

If you have masonry fireplace (not prefab), I think you want an insert to really gain heating value.

Pete

 

[granpajohn]

I think lovers of fire, especially those of us who live in temperate climates, have owned or looked carefully at ways to keep an open hearth fire while still scavanging more and more heat from it. So, just a few quick notes on my own research.

1. There are doors made that are airtight, and good looking. They have gaskets and cam locks. They are costly.
2. Combined with a tube heater style of device, they make heat. But, the two items have to fit together well.
3. Items 1 and 2 together will cost about the same as an insert. The monkey wrench is the possible chimney relining that probably wouldn't be needed with the doors; might be with the insert.
4. As you know, the insert will make more heat with less wood. But consider that it may also last longer. Depends on burning habits, of course.

It sounds like I'm trying to sell the insert idea, but I think the door/hearth heater system is good for fellow southerners who are interested in architectural appearance and don't plan to burn fires too often.

In my own case, we used a very nice door/tube heater combination for a few years because I received it as a hand me down. It had glass, not ceramic, doors which don't radiate like the ceramic glass of the Quadrafire. So take that into account also.

OK, my post is too long. Sorry.

 

[webbie]

There are a lot of variables. An inside fireplace with doors may perform well, but an exterior one is not going to be very efficient.

Another item of big concern to me is that most fireplaces are incorrectly built, and the only reason more homes do not burn down is that the fireplaces see little or no use. Put some doors on them, and use them for many hours and it would be easy to overheat house framing that was too close. With an insert, you have an extra two walls of steel...

 

[gpcollen1]

I have an insert, freestanding and a fireplace with doors that do not seal - dare I say on an outside wall. I can throw some serious heat from my fireplace but it is at a large expense of wood. I save some large pieces for some overnight burns on the weekend too so I have a few coals in the morning and burn a ton of wood when I cook here good. I do love cooking some steaks in the fireplace though. Problem is, with no fire, all it does is slowly radiate cold air. So in a cold climate I would say no way on the fireplace v an insert. It is not even close if you want heat and efficiency.

...and my house will not burn down b/c of my fireplace...