most efficient zero-clearance prefab fireplace?

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For delivering heat into an area, a fireplace, even if enclosed, is going to be much less efficient than a free-standing stove. It will require a blower to get the heat out which further impacts overall efficiency.
 
Well, yeh, I know, but a free standing stove is not an option. So, how might one best judge efficiencies WITHIN the category of inserts or fireplaces. I still don't know what to call what I want. What is a wood stove that is built into the wall in new construction with a large glass fire viewing area? There seem to be lots of different terms out there, and I do not want to waste the time of the folks kind enough to respond to my questions.
 
Prefab fireplace will do. I updated the thread title to attract more directed attention.
 
years ago when on a vacation in Canada we stayed in a cabin. in the main open room theyre was the nicest fireplace set up id ever seen. the hearth had been built with lots of stone and they're were 4 vents built in. two down low down low and 2 up high. no fan just natural convection. it had glass doors and air was from outside for combustion. this unit heated the place extremely well. i noticed a couple pictures on this site using that design. pete
 
It is true that a blower will improve efficiency but if you follow a lot of threads here of people with free standing stoves, many of them are jury-rigging all sorts of fans to move the heat around anyway.

I have the central heat blower option on my RSF. It's a large external 650 CFM blower, not one of those dinky squirrel cage fans inside. I pull cold air up from the crawlspace floor, filter it through a 3M Filtrete furnace filter, and blow it up across the firebox. The warm air moves through the house and is pulled back down into the crawlspace where it warms the underside of the floors.

In milder weather I often turn off the fan to reduce how much heat I pull out of the stove. In the case of a power failure in really cold weather, the stove obviously won't be as efficient but there is enough convection for it to work.

As for comparing manufacturer claims, well... they say figures never lie but liars always figure. Take the numbers with a grain of salt. More important is to get a stove with a large enough firebox for long enough burn timess and sufficient BTU output but not so big that you need to open a window to cool the house off. My 3.1 cu ft stove is a tad on the small side when it gets down near -40 but then in milder weather it's hard to not get it too hot in the house. Ideally one needs two stoves, a big one and a small one to meet all conditions.
 
Quadrafire 7100, RSF Opel, Kozy Heat, FPX Extrodinair, BIS Ultima are the main companies making these units. Not sure about the most efficient. Maybe the Opel II or the Kozy Heat 241?
 
I just installed the Osburn Stratford in my 2,500 sq ft home and it is doing a VERY nice job at heating my home. Great price too!
 
i have a enviro venice
it is a ZC insert.
it heats my 3100 sq foot home very well and only needs supplemental help from the furnace when temps are below 12-20F for a long period of time.
 
BeGreen said:
Prefab fireplace will do. I updated the thread title to attract more directed attention.
Ah, I did not notice the update. Thanks. So, what I need is a prefab fireplace, heh? Does that automatically mean it will be an air tight, closed type system with a glass viewing area?
Thanks for your help, Richard
 
heatwise said:
years ago when on a vacation in Canada we stayed in a cabin. in the main open room theyre was the nicest fireplace set up id ever seen. the hearth had been built with lots of stone and they're were 4 vents built in. two down low down low and 2 up high. no fan just natural convection. it had glass doors and air was from outside for combustion. this unit heated the place extremely well. i noticed a couple pictures on this site using that design. pete
So, Pete,
This was a custom designed and built unit, heh? Santa Cruz seldom gets below 40 degrees F, so that might be a bit much. I am concerned about fan noise, so convection is appealing. Have you ever seen such a unit as you described sold as a package?
Thanks, Richard
 
LLigetfa said:
It is true that a blower will improve efficiency but if you follow a lot of threads here of people with free standing stoves, many of them are jury-rigging all sorts of fans to move the heat around anyway.

I have the central heat blower option on my RSF. It's a large external 650 CFM blower, not one of those dinky squirrel cage fans inside. I pull cold air up from the crawlspace floor, filter it through a 3M Filtrete furnace filter, and blow it up across the firebox. The warm air moves through the house and is pulled back down into the crawlspace where it warms the underside of the floors.

In milder weather I often turn off the fan to reduce how much heat I pull out of the stove. In the case of a power failure in really cold weather, the stove obviously won't be as efficient but there is enough convection for it to work.

As for comparing manufacturer claims, well... they say figures never lie but liars always figure. Take the numbers with a grain of salt. More important is to get a stove with a large enough firebox for long enough burn timess and sufficient BTU output but not so big that you need to open a window to cool the house off. My 3.1 cu ft stove is a tad on the small side when it gets down near -40 but then in milder weather it's hard to not get it too hot in the house. Ideally one needs two stoves, a big one and a small one to meet all conditions.

Thanks for the detailed response. As it seldom gets below 40 degrees F here, I certainly want to be careful not to oversize. From what you say, it would seem that it is NOT possible to crank a large firebox down so that it just puts out a small number of BTUs and that one must size the box according to the most common needs, not the maximum needs. IOW optimize the stove for average conditions, not the extremes. Is that right?
R
 
You could start by visiting some local fireplace shops and grabbing some brochures and comparing efficiency numbers. I always oversize a little with the EPA fireplace since their heat is controlled so much by the fan speed. A lot of times, these Hearth Shops are staffed with fireplace and stove experts who can answer a lot of questions for you.
 
Franks said:
You could start by visiting some local fireplace shops and grabbing some brochures and comparing efficiency numbers. I always oversize a little with the EPA fireplace since their heat is controlled so much by the fan speed. A lot of times, these Hearth Shops are staffed with fireplace and stove experts who can answer a lot of questions for you.

Will do. Thanks.
 
yeah,the set up in canada, im sure it was a custom built hearth. i have never seen anything since then like it .i hope you can find sompething suitable that will work out for you. enjoy the hunt, pete
 
rorser said:
IOW optimize the stove for average conditions, not the extremes. Is that right?
R
That depends on whether you intend the fireplace to provide 100% of the heat and you expect the heat to be as even as the furnace. You probably don't want to be getting up in the middle of the night to feed it and if you're obsessing about efficiency, opening a window to let in some cool air will send you to the loony bin.
 
To get back to your original question - do efficiency ratings mean anything? Well, I'm sure they mean something, but I think there are a ton of other considerations that probably outweigh them.

First of all is your location. If it seldom gets below 40 degrees F, that is a big consideration. If you read this forum you'll find that when temps begin to trend UPWARD toward 40 degrees, many folks consider the heating season to be coming to a close (or just getting started). Chances are, any of the EPA efficiency-rated units you're looking at will be able to blast you out of the house with their heat output.

Next consideration is your fuel. I would hazard an educated guess that the difference between the highest-rated and the lowest rated unit you are looking at is less than the difference caused by a good load of fuel compared to a bad load of fuel. And you may not always have 100% control over the quality of your fuel. Keep that in mind as you make your decision.

Next consideration is simply style and taste. What do you want in terms of how the unit will look with your home's decor? There are some differences from one unit to another. They may not be huge differences, but you'll probably find one or two that you like the looks of better than others.

Another consideration is overall quality of construction. This one is really hard to judge. How can you tell? I doubt you can rank the various manufacturers on this, but when you narrow it down to your top choice, you might ask around among experienced folks and industry experts to try to get a feel for that manufacturer's reputation.

Interestingly, my dealer recommended that I compare the weights of the various units I was considering. How many pounds of stove do you get for the money? This can be expressed as a simple ratio of pounds per dollar. My final two choices were about equal in price, but one was 350 pounds while the other was 600 pounds. What would you think of that difference among your two finalists? (Remember, once the stove heats up, its weight has a bearing on how long it will hold onto the heat.)

At any rate, if I were you I wouldn't give a lot of weight to efficiency ratings.

Hope this helps.

-Speak
 
LLigetfa said:
rorser said:
IOW optimize the stove for average conditions, not the extremes. Is that right?
R
That depends on whether you intend the fireplace to provide 100% of the heat and you expect the heat to be as even as the furnace. You probably don't want to be getting up in the middle of the night to feed it and if you're obsessing about efficiency, opening a window to let in some cool air will send you to the loony bin.

You raise an important point, about heat all night. We have no need for heat after we go to bed. It never is that cold here, and we will be sleeping in a totally different part of the home under an electric blanket. Important to us in priority order are: 1. ambiance with great view of the fire through large glass area, 2. quiet fans, 3. efficiency, 4. ease of use and maintenance. And, of course, the unit must be attractive and fit with our architectural style, but there seem to be many out there that do.
Any more thoughts or comments would be appreciated.
 
If quiet fans are important, my bis ultima doesn't fill that bill.I like the fireplace for what we use it for,but the fans are loud enough to drive me nuts at times.
 
Your requirements sound very familiar to mine when I was looking. I choose FPX 36 (Hmmm, I bet you couldn't tell from my profile eh, hahaha!) and so that's why maybe I'm partial to recommending them. Yea, I didn't want to hear any fans either, or see any cords either hanging out when I'm enjoying it, so the ability to remotely locate the blower allows it to be very very quiet, actually even quieter than the furnace blowing air thru the vents when it runs (which has only run once since November, so that shows you how much I'm running it). BTW, I live in Sacramento so similar climate to you.
 
With the RSF you can use an in-line blower and mount it far away from the stove. I find mine to be reasonably quiet and pushing cold air to the stove works well. With the variable speed blower, I can control how much heat I extract from the stove and spread around.
 
rorser, if I read this correctly, you're more into the appearance and ambiance of the insert, vs. long burn time- correct? Efficiency would relate to smoke out-put- ie, keep it clean. I have no experience with inserts, but almost anything EPA certified will burn clean, if you do your part. That means seasoned wood. And that may take awhile in your area-too much fog (25 yrs.-born and raised just S. of Salinas). Pick a heater you like, but for the first year or two, get your wood from someone around King City- nice and dry down there. Oh- seasoned Eucalyptus does burn pretty good. ;-)
 
Sacramento, heh?
Yes, your requirements would be very similar.
I will definitely take a look at your unit. But, I am especially appreciative of the idea of putting the fans in a more isolated location. I never thought of this, but doing new construction, this would certainly be an option.
Thank you so much for your input,
Richard
 
I'll have to say that if it rarely gets down to 40 deg. I don't think you want an actual fireplace. I've got Kozy Heat's Z42 and when it's above 30 deg. I've got to open windows. That's not even using a blower. I'll use a blower at night if the temps fall below 20 and even then the family room will be 80 plus. I understand wanting to watch a fire, mine is so cool to look at thought that big window, but the heat - you'd have to film it and watch it on TV later. In order to get those secondary burns that makes watching the fire almost as enjoyable as watching TV you've got to burn a fairly hot fire - again, the heat would blast you out of there. If you would try to just burn small fires then you might run the risk of not getting the chimney hot enough to keep it clean. Personally, I like a clean chimney. After burning 5 cord of wood I'll sweep my chimney out and I'm lucky if there's 4-5 cups of ash come out of it. Maybe you should consider a gas fireplace.
 
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