Using a wood burning fireplace for heat

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JHD

New Member
Dec 7, 2015
19
West Michigan
Hey how's it going, looks like everybody here is pretty knowledgeable on the subject, so I had to join.

I just bought a manufactured house and it has a Marco fireplace already installed. I've never burned wood before but the fireplace was tempting so I cut and split a bunch of wood and started burning. I went for Elm because I read it didn't have to be seasoned long before burning. I plan to start my pile for next year so its all seasoned by next winter.

Anyway, are there any tips for getting the most heat out of a normal chimney fire place without buying an insert? Like using the doors a certain way or fan in addition to the built-in blower? Any tips would be much appreciated.
 
Your ZC Fireplace will give you warmth, not heat. It's like having a campfire in your living room. If you sit close enough & rotate so that all sides face the fire, then all sides will get warm. You will be wasting your time & firewood, & most (90%) of your heat will go up your chimney. Along with THAT heat, any air that you have warmed via other means, gas or oil furnace or boiler, electric heater or whatever, will also go up your chimney. You need an airtight system to heat reliably & inexpensively. A fireplace doesn't cut it.
 
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Thanks for the reply. So, I've heard that before. in the 2 days that I've burnt wood in here (not seasoned), I am able to keep the majority of my rooms at about 80°F, as long as I keep the fire going, adding about a half log every 20 min. At this rate, my furnace never has to kick on.
I know this is more labor intensive than a wood stove, but with that much warmth output, is this situation really inefficient?
 
My brother tried that years ago. He put doors on it. The glass broke a few times from the heat. I don't think it worked to well, but it was a big house. I've heard many of these aren't made for ripping hot fires. The small fire box prevents you from putting a lot of wood in it. But give it a try, just be careful.
 
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To me, one of the biggest problems is once the fire is burning out, you lose the radiant heat you were getting but as long as there are active coals, the damper has to stay open and the hot chimney continues to pull warm air out of your house. Most glass doors cant be burned shut but if yours are pretty tight and you can close them once the flames hive died off, that will help.
 
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I guess the thing that saves it the most is the built-in blower, it does seem to blow the heat across the room pretty well, although at times when adding wood it gets smokey in the room. And yet the box isn't very big so you have to add wood a lot and cut the logs short.
 
Good points, noted. looks like next year i might get a wood stove insert lol.
I doubt you can put an insert in that fireplace what does the manual say? To my knowledge there are only a couple heatilator zeroclearance fireplaces that allows an insert to be installed in them
 
I guess the thing that saves it the most is the built-in blower, it does seem to blow the heat across the room pretty well, although at times when adding wood it gets smokey in the room. And yet the box isn't very big so you have to add wood a lot and cut the logs short.
Yes you may be able to heat with it loading like that but what happens when you go to sleep? And how much wood will you go through. I can heat my house one one load for 8 to 10 hours
 
Yes you may be able to heat with it loading like that but what happens when you go to sleep? And how much wood will you go through. I can heat my house one one load for 8 to 10 hours
Bholler
Yea I don't get anywhere near that, I get maybe 3 hours out of a load, which is about 5 quarter split logs at 16" long a piece. Because it's not sealed like a wood stove it rips thru the wood, thus producing good heat but for a short time.
I put the fire out when I go to sleep because of this, but I figure if I can keep the fire running all day then I've cut my propane use about in half which is better than nothing. But yea I do need to upgrade to something, I'm only 4 days into my wood burning experience haha
 
Perhaps while shopping around for a stove you could either look for a zero clearance epa fireplace, or maybe a separate woodstove in a different area with its own class a chimney.
 
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OK I have an addendum question to my original one.
After a couple days of burning, I have realized this is not going to work! Too smoky, way too quick burning, etc. I need either an insert or a wood stove.
My question is, if I install either one, can I just connect it to the existing liner that goes up the chimney? I've looked up there and there is stove pipe all the way to the top, so could I just take out my Marco fireplace and change it out? I have tried to google this question and I can't get the answer I'm looking for.
 
Your answer is NO. The chimney in there is air cooled & not rated for
the higher temperatures that an air tight wood stove can reach.
If you pull it out, pull it ALL out, venting included.
Your other option is to drop an insulated liner into the existing vent & firebox,
& make a positive connection to a wood burning insert or a free standing stove on the hearth.
 
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Your answer is NO. The chimney in there is air cooled & not rated for
the higher temperatures that an air tight wood stove can reach.
If you pull it out, pull it ALL out, venting included.
Your other option is to drop an insulated liner into the existing vent & firebox,
& make a positive connection to a wood burning insert or a free standing stove on the hearth.

So we are assuming the existing liner in the chimney is definitely not high-temp rated? I found alot of sketches that showed a liner only going up to the throat, then bare chimney walls up from there. They made it seem like you can attach your liner to the highest point of the existing one?
I dunno, this is all way more complicated than I first thought!!
 
Not assuming. The ZC boxes allow SO much air in the front that the chimney vent doesn't get that hot.
Any Direct connect or "SLAMMER" installs that you saw pictures sketches or diagrams of are in masonry,
Terra Cotta lined chimneys. Not thin walled steel.
 
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So due to the chimney getting too hot from the fire being airtight, it would not be a good idea to fab some iron woodstove doors to fit over the fireplace opening? Would that make it too hot for my chimney?
 
ZC boxes are designed to burn with the doors open. Ask anyone with tempered
glass doors how they made out when the shut those doors with a fire burning.
The tempered glass shatters when it overheats.
If you put solid doors on your fireplace, you will be violating all the testing that
was done before it was deemed safe to put on the market. You absolutely do NOT want to do that.
Fire will do two things. It will HEAT your house or it will EAT your house. It doesn't care which you want.
You are fighting a losing battle trying to heat with that unit.
 
It also says very clearly in all of the marco fireplace manuals i found.

"Do not use a fireplace insert or other products not specified for use with these fireplaces"
 
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I see that now. Well, new liner and a woodstove isnwhat I'm gonna go for. At least my wood will have a year to season and I got $.80 a gallon propane this year haha.

Thanks for all the help everyone, definitely helped out. I'm happy I found a nice grove of red oak by my house that I got permission to cut, I'll update when I toss one on the fire!
 
By the way, found a good link for looking for wood if you need to know the heat value in BTUs per cord. Didn't want to gain all this info without leaving something behind.

(broken link removed)
 
JHD I'd agree with your decision to go for a liner and woodstove. Fireplaces can be a net 0 or worse in terms of heating because of all the air they pull in from outside (remember that air is still being pulled and going up your chimney in as your fire burns down). I adapted my fireplace by having an wood stove insert installed (with chimney liner). Was cheaper and took up less room than a standalone. Very happy with it and it puts out a good amount of heat.
 
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I had the fellow who installed my insert also put in the liner. I could not find the invoice so I don't have the price, but I don't think it was not too bad relative to the cost of the wood stove. I recall the price was pretty dependant on the length of the chimney. Someone who does wood stove maintenance in your area could probably give you an estimate.
 
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[Hearth.com] Using a wood burning fireplace for heat
I'm rethinking my strategy. Still cutting wood everyday with the mild winter we're having. I might just sell this whole first round of wood and see if it pays well... Hey I enjoy splitting wood for some reason.

Anyone have an idea what kind of wood this is? It has been dead laying in a field, has lateral splits down the sides. It splits kinda easy, no color differentiation throughout. Most of the bark has fallen off and its smooth, its not heavy but not light, and is bright colored with a tight grain running mostly straight. I'm guessing either elm, ash or maple. I keep reading that elm is stringy, this isn't bad.
[Hearth.com] Using a wood burning fireplace for heat
 
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