Significant heating difference between woodstove as insert or freestanding?

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donalyncs

New Member
Aug 12, 2008
3
Northern CA
I have combed this site but am still not confident that there is a significant difference between putting the new Avalon Rainier wood stove we just purchased in our brick fireplace as an insert or freestanding in the same room. We have a 1,650 sq ft ranch with the living room on the south end. We live in a very mild climate (lows 30's, highs 60's year round). We have the space to make it either single or double wall stove pipe if placed freestanding. Our hope is to get the most heat out of our wood (of course) to use as primary heat for the house if necessary (we are comfortable at 60 degrees inside). If we insulate the firebox well and place the stove as an insert, is the heating significantly less than freestanding? We would prefer it as an insert if the heating difference is not significant. I am not going by BTUs because it would be the same stove, only a different placement and so the stove will "put out' the same BTUs either way. I am concerned about us actually being able to get the benefit of all those BTUs where ever we place it. Our main criteria is NO BLOWER! Can anyone out there give us some guidance on how much difference REALLY it makes to place it free-standing or as a n insert and do you have any tips on installing it as an insert that would maximize getting the BTUs out to the room instead of up the chimney or stored in the brick? Thanks much.
 
I removed a 3.x CF steel insert from a masonry chiney and installed a freestanding 2.3 CF stove. I hated the blower on the insert and really like the silence of my freestanding stove. Both stoves could heat the home but the freestanding does it easier and with less wood than the much larger 3.x CF stove did. I would never intentionally insert a stove into a fireplace unless as a last resort. The brick surrounding the sotve is constantly sucking btus and wicking them up the chimney via the masonry while preventing the line-of-site radiation from shooting out around the room.

Masonry is a poor insulator which is why it is a poor hearth material. It is a great thermal conductor which is why it always feels cool to the touch. It will suck the heat right off of 5 of the 6 sides of your stoves.
 
You get more heat from a same sized freestanding unit due to the greater exposed surface area for radiant heat.

Energy is saved without operating a fan and your heat source is not effected by a power outage when you free stand.

I just went through the hassle of figuring out an installation of my replacement freestanding stovewhen an insert would have slid right in the fireplace.
 
I agree. Freestanding is the way to go unless room space is REALLY minimal (most people seem to think that it is, but many make a stove work). More surface area of hot surfaces bleeds more heat into the room.

I bet you are looking for a ratio or formula to compare the two . . . how many cubic ft of insert is equal to X cubic ft of freestanding.

My house is the same size as yours, although different configuration (2 story Dutch gambrel, some wasted behind-the-walls space on second floor) heated by a 2 cubic ft firebox. The back of my freestanding unit is about 4 inches from the the front opening of the fireplace. Even with a somewhat angled heat shield to deflect a small percent of heat ultimately lost to the back masonry, I still get the benefit of radiating heat from the exposed sides and top of the stove. My 2 cubic footer works well for most days here in New England.

Lots of people here seem to talk about a blower being essential for an insert. Drawbacks: potential noise, potential replacement part, needs electricty (although I bet a battery/generator back up is workable).
 
Good question. Just for the heck of it I decided to compare a Hearthstone stove with an insert.

The insert I looked at was the Clydesdale. Rated at 60K Btu/hr for a 2.4 cubic foot firebox. So 25K Btu per cubic foot.

A similarly sized stove from the same company is the Bennington. Rated at 70K Btu/hr for a 2.5 cubic foot firebox. So 28K Btu per cubic foot.

That's probably representative. All things being equal an insert with a blower can get within 10% or so of the freestanding unit but will never equal its output. Without the blower it's probably 30% or so less heat delivered than a stove (this figure is a pure guess).
 
Pretty simple actually. If you do not want a blower then go with a freestanding stove. Myself, I put a big honkin stove half in and half out of the fireplace. But I use the blower for distribution of warm air to the rest of the house. Ya gotta move that air somehow.

fossil has a monster free stander out in the open and still uses the blower. For the same reason I do.
 
Please remember that insert ratings do not take efficiency (or loss of it) related to installation in an exterior chimney into account!

Also, most ratings are simply made up and guessed at - nothing to compare from one brand to another or even within one brand.

We took a quick stab at it with our burn time calculator - related to firebox size......
https://www.hearth.com/econtent/index.php/articles/burn_time_calculator

Another thing to keep in mind is our "false" perceptions. A person who has used an open fireplace or a franklin stove will be greatly impressed by the heat output and efficiency of a 40% efficient insert setup....and rightly so! But someone who lives in Northern VT and has burned wood for decades is very likely to understand the concept of an interior chimney and freestanding stove.

For those who burn a cord or two a year for aux. heat and recreation, this may not be a big deal. But for the max "MPG" from a stove, all such factors should be considered.
 
donalyn said:
Our main criteria is NO BLOWER!

Why so adamant against the blower? If it is "only" because of the noise you should listen to one in a stove shop before ruling it out. On my insert the blower at 50 or 60 percent speed is very quiet. Up around full speed it is bit loud but not offensive. I figure we'll have it on high only for the overnight burns on when we'll be sitting in a different room.
 
Not too sure about all this but I'm listening too. I have two wood stoves. Both are Jotul 3CB's. One is freestanding in the basement, and the other is on the first floor and set into my fireplace. My chimney runs up the center of my saltbox. It seems to me that the fireplace/hearth installation puts out a lot of heat. The masonry does suck up a lot of the heat because it seems to hold the heat and radiate it for days. The entire chimney radiates heat through the walls, up the stairs, and into the second floor bedroom, into the closets too. Think nice warm towels and pajamas. I read in an architectural building book that a mass of brick will slowly store, and then slowly release massive amounts of energy, more than any other material.. That is the idea behind passive solar features in houses that use the daytime sun to heat a large brick surface. The stove in the basement will fry the basement occupants, nicely heat the first floor, but once it is out, all the heat is lost.
 
BrotherBart said:
...fossil has a monster free stander out in the open and still uses the blower. For the same reason I do.

And dat's a fact. And we love it. Blower's on a rheostat. Don't want to listen to it? Turn it off. Want to circulate air/move the heat out into the room? Turn it on to some pleasant level. Going to bed in the back room? Turn it up to max. Wouldn't have it any other way. Rick
 

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Your stove will make the same amount of heat whether it is in a chimney or freestanding. What happens to that heat after it is produced is the topic at hand. When you shove the stove into a brick fireplace with a big honking heat sink of a chimney sticking way up into the sky, then a percentage of that energy will be lost to the heat sink and blown away by the wind. So your freestanding will be able to deliver that heat to the room and so you can run it less to consume less wood. That equates to efficiency.
 
I have owned both an insert and free standing stove. Both with aproximatly the same size fire box. There is no question that the free standing stove does a better job of heating in my situation, even with the blower on the insert. The problem with my comparison is that they were in completely different style of houses and the insert was in a fireplace on an exterior wall without a block off plate.

If your fireplace is on an exterior wall you will need a blower to capture any significant heat, as most of the heat radiated from the sides and back of the insert will end up heating the outdoors.
 
donalyn said:
We live in a very mild climate (lows 30's, highs 60's year round). We have the space to make it either single or double wall stove pipe if placed freestanding. Our hope is to get the most heat out of our wood (of course) to use as primary heat for the house if necessary (we are comfortable at 60 degrees inside).

Big heat output is not a major concern in your type of climate but if you want to get the most out of your wood then go with the freestanding.
If you like the look of a woodstove in a fireplace (I do too) then go for it and see if you are satisfied with the heat output. You could always
add a fan later if needed.
 
I've learned on this forum that in the Bitter Cold NE, it is considered extremely important to wring every last btu out of the stove in most applications. Oversizing the stove for the area to be heated is not just condoned, it is highly recommended by forum members who live in colder climes, where periods of zero and even sub-zero temperatures require that maximum heat must be coaxed from the stove.

I've learned from personal experience that in milder climates, wood stoves don't have to work so hard, and oversizing the stove can be a disaster. In fact, the biggest single complaint we've heard throughout nearly three decades in the wood stove business in the relatively mild climate of Bellingham, WA has been that the stove is too big for the house.

Donalyn, you say that where you live, the Winter temperature spread is 30 - 60 degrees, and the family is comfortable with indoor temperatures of 60 degrees. In other words, a woodstove that is capable of creating an indoor degree change of 30 degrees (30 to 60) would fit this application on your coldest Winter days. In my opinion, you don't need to be concerned about a few degrees heat loss to the masonry.

The Avalon Rainier is a very good heater, with a large airspace in the plenum and an interesting slope-backed geometry that promotes the flow of heated air uphill and into the room. When we sold Avalons, we installed many, many Rainier inserts here in the Coastal Pacific Northwest without blowers, advising our customers that the blower was an easy retrofit should they find they need it.

Nobody ever came back for a blower.

Donalyn, given your description of your heating needs, I wouldn't hesitate to install a Rainier without a blower as an insert.
 
Webmaster said:
Please remember that insert ratings do not take efficiency (or loss of it) related to installation in an exterior chimney into account!

Also, most ratings are simply made up and guessed at - nothing to compare from one brand to another or even within one brand.
.

This is a very interesting comment.

I had assumed that the ratings such as "will heat XX square feet" are meaningless because they ignore climate and insulation. Now you are saying that even BTU/hr is not a valid way to compare stoves? Even within a brand (which should have the same test standards)?

I would have thought that with EPA ratings the stove performance was pretty straight forward... if it is not going up the flue as particulate it was burned and would put heat into the house.

Certainly the effect of having an insert in an outside masonry chimney would skew the numbers to some degree. But isn't that what the what the shroud and blower are supposed to address and therefore minimize the impact of?

If you were to take your comment at face value it would say that there is NO valid test data and therefore only the opinions of users has validity. Put another way, there is no reliable data published by manufacturers?
 
thechimneysweep said:
I've learned on this forum that in the Bitter Cold NE, it is considered extremely important to wring every last btu out of the stove in most applications. Oversizing the stove for the area to be heated is not just condoned, it is highly recommended by forum members who live in colder climes, where periods of zero and even sub-zero temperatures require that maximum heat must be coaxed from the stove.

I've learned from personal experience that in milder climates, wood stoves don't have to work so hard, and oversizing the stove can be a disaster. In fact, the biggest single complaint we've heard throughout nearly three decades in the wood stove business in the relatively mild climate of Bellingham, WA has been that the stove is too big for the house.

Donalyn, you say that where you live, the Winter temperature spread is 30 - 60 degrees, and the family is comfortable with indoor temperatures of 60 degrees. In other words, a woodstove that is capable of creating an indoor degree change of 30 degrees (30 to 60) would fit this application on your coldest Winter days. In my opinion, you don't need to be concerned about a few degrees heat loss to the masonry.

The Avalon Rainier is a very good heater, with a large airspace in the plenum and an interesting slope-backed geometry that promotes the flow of heated air uphill and into the room. When we sold Avalons, we installed many, many Rainier inserts here in the Coastal Pacific Northwest without blowers, advising our customers that the blower was an easy retrofit should they find they need it.

Nobody ever came back for a blower.

Donalyn, given your description of your heating needs, I wouldn't hesitate to install a Rainier without a blower as an insert.


wow!! there you have it.... right when you guys were making me feel bad about my summit insert!!!!
i believe that freestanding gives off more heat because its right there with you so it appears to give off more........my old harmon exception blew me out the room when it was going good but ... the whole stove was next to me! my summit insert ..whe it get cranking i can't stand in front of it either......it just better to have a blower so the heat behind it comes out..... people have stuufed ceramic insulation around them to keep theheat from going into the walls.....i have tiles around my fireplace and they get to hot to touch! so i don't think my heat is going up the chimney...(but it is an interior chimney with a block off plate)

BOTTOM LINE...........
i love my summit insert guys! so you freestanders stop it!
 
EngineRep said:
This is a very interesting comment.

Now you are saying that even BTU/hr is not a valid way to compare stoves? Even within a brand (which should have the same test standards)?

I would have thought that with EPA ratings the stove performance was pretty straight forward... if it is not going up the flue as particulate it was burned and would put heat into the house.

Certainly the effect of having an insert in an outside masonry chimney would skew the numbers to some degree. But isn't that what the what the shroud and blower are supposed to address and therefore minimize the impact of?

If you were to take your comment at face value it would say that there is NO valid test data and therefore only the opinions of users has validity. Put another way, there is no reliable data published by manufacturers?

Now you have it...exactly. I won't repeat what you said, but that is correct.

EPA does not test for efficiency, they use defaults. Inserts are usually assigned the same efficiency as the freestander of the same brand.....if the firebox is the same.

There is not a standard procedure for real world cordwood testing......

I'm certain that many manufacturers use comparitive figures within their own brands to avoid trouble, at the same time they (once again) are not testing them in exterior masonry enclosures.

After all is said and done, using the cubic feet of firebox and wood types, etc. (as per our calculator) will give you a more accurate comparison.

Also, when it comes to efficiency, less particulates does not mean better......you can lose HEAT (stack loss) up the chimney even on a super-clean burn. There is also excess air - which relates. A lab guy (Corie) can probably explain it better.
 
Wow! Thanks everybody. So much help. More than I expected. We are taking all your comments in. The brick chimney is an interior chimney so we are Ok there. The fireplace came with a pellet insert when we purchased the house and we really disliked the blower noise and the dependency on an outside energy source, electricity, to get heat when we needed it so we sold it. Currently we have a whole house natural gas HVAC system and we all know which direction gas prices and availability are ultimately going. I'm expecting over time, with strained resources in our isolated area (Humboldt County, CA) that over the coming winters, power outages may be progressively longer and longer and we want to be prepared. My husband and I are not spring chickens (more like a stewing hen and a tough old bird) and, frankly, if we can trounce around the property, fell and lug 20% less to be comfy by doing the freestanding we'll go that route. Otherwise, it would be easy to push the stove into the existing fireplace drop in the pipe, stuff in some insulation around the stove and put in a block plate and call it good (not to mention no visit from a building inspector to do it). If this changes any of your advice, please share your thoughts some more!
 
iceman said:
...i love my summit insert guys!

And I love my freestander, ice...and that's all that matters. It ain't about who's right or wrong, because there is no right or wrong that works for everyone's situation...it's all about how best to bring warmth & comfort to ourselves and our loved ones during the cold season in our particular circumstance, abode, surroundings and climate. I'm really happy that you're so pleased with the performance of your insert...makes me feel warm for you and for your family. Burn long and prosper! Rick
 
I understand about the heat going up the chimney on an insert.

What I don't understand is why the calculator differentiates between cat and non free standers but not between cat and non cat inserts.

I'm going to insulate above and around my insert with kaowool this year, to see how much of a difference it will make.

I know I can block a bunch of the heat from going up the chimney, I just hope the stove doesn't get too hot.
 
karl said:
I understand about the heat going up the chimney on an insert.

What I don't understand is why the calculator differentiates between cat and non free standers but not between cat and non cat inserts.

I'm going to insulate above and around my insert with kaowool this year, to see how much of a difference it will make.

I know I can block a bunch of the heat from going up the chimney, I just hope the stove doesn't get too hot.

if its an exterior chimney yes interior doesn't matter .... i did mine and didnt see big diff the biggest diff was taking off the shroud BUT...... not enough for me to leave it off my insert...(not knowing what you have) is designed fairly well....it kept over 2000sq ft warm and the insulation told me i need at 8 more inches to be brought up to what today specs and reccomendations are...
also keep in mind that my house is 80 ft wide and the chilly parts are of course 60 feet away but that was lower to mid sixties when it was below 10 without the right amount of insulation.......

to the op freestanding are wonderful... and yes you may be able to go smaller.... however i wouldn't .... you can open a window to cool a house down...... but if you buy to small and can't heat it you'll be really ticked ..... get the biggest one that fits your eye and budget...you can learn to control heat output with experience and us:)
bottom line whether free or insert get a bigger one at least 3.0 cubic feet
if your house is 2000 get one for 3000 min
 
fossil said:
iceman said:
...i love my summit insert guys!

And I love my freestander, ice...and that's all that matters. It ain't about who's right or wrong, because there is no right or wrong that works for everyone's situation...it's all about how best to bring warmth & comfort to ourselves and our loved ones during the cold season in our particular circumstance, abode, surroundings and climate. I'm really happy that you're so pleased with the performance of your insert...makes me feel warm for you and for your family. Burn long and prosper! Rick

don't mind me i am jealous i wish i coulda got one and then had a pretty wall behind it.... but where i live if i ever sold my house MOST people would think neg about a big stove in my living room ...... they would rather pay for oil
 
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