combustion efficiency 600 vs. 1100

[sgcsalsero]

Newb question, just point me to the right thread if needs be. .

Author quote "consider .. . .1/2 to 2/3s of the fuel value of wood is locked up in gases and volatile liquids. These emerge from the wood as it is heated in the firebox. If they do not burn, it is like throwing fuel away. Burning the gases requires temperatures in the 1100 to 1300 degree range."

How is possible that the manufacturer of my insert can claim 75% efficiency when I am burning at literally half (550 to 600) of what is required for 'good combustion', is the engineering that good ? Assuming a lot of the efficiency gain is from secondary combustion at the manifold of stainless tubes (assuming most folks have a similar setup)

Thanks

Note: author is D. Lyle, book on masonry stoves

 

[elkimmeg]

well surface temps and not the same as the ones occuring in the fire box Inside that fire box 1100 degrees or more is happening

 

[precaud]

elk is right. Next time you light a fire from scratch, watch the baffle or shelf above the fire. Initially it will collect carbon and blacken, then at a certain point the carbon will burn away. That's your clue that temps in the firebox have passed the 1100 mark.

 

[Martin Strand III]

Not so fast, Pvt Johnson.

SGC has (re)discovered what I've been lamenting about for some time (very old post of mine: "The Dichotomy of Burning Wood in a Metal Stove").

While I agree that temperature in the firebox may reach 1100* F and show a surface temperature of less, the amount less has been empiracle (read anybody's guess), it does this not as the rule but as the exception since a metal stove has to restrict incoming air to prevent over firing, thus be "dialed down", thus not be optimal burn temperature for burning wood fuel.

To look at this another way, IF the firebox temp is around 1100* F and the surface temp of your stove shows 500* F, or so, the difference is going up and out your chimney!

Granted, newer Phase II stoves and those with catalytic combustion add-ons do get more heat out of burning wood than older pre-Phase II stoves, they all (metal stoves) require restriction of incoming air which means there is more waste of potential heat from the fuel compared to a design where the fuel could be burned without incoming air restriction.

Aye,
Marty

 

[precaud]

To look at this another way, IF the firebox temp is around 1100* F and the surface temp of your stove shows 500* F, or so, the difference is going up and out your chimney!

There's only two possibilities: either it's going up the chimney, or it's being stored in the significant mass of the stove's materials (metal, firebrick, whatever), which are capable of storing quote a few btus. This is the heat transfer efficiency. From what I can see, it varies greatly from stove to stove, much more so than the combustion efficiency. It really has to do with the flame path, and how exposed it is directly to the outside surfaces of the stove.

I happen to own two stoves which both have very good combustion efficiency, but which pretty much bracket the extremes of heat transfer efficiency. The Morso 2110's is fairly low, because the flame path is shorter and it has internal baffles which almost completely cover the flame path. The Quad 2100's is amazingly high, with a long, almost entirely exposed flame path. I'd guess there's a 15-20% difference between the two. Under normal operation, there's 100F difference in stack temps between them.

Granted, newer Phase II stoves and those with catalytic combustion add-ons do get more heat out of burning wood than older pre-Phase II stoves, they all (metal stoves) require restriction of incoming air which means there is more waste of potential heat from the fuel compared to a design where the fuel could be burned without incoming air restriction.

It's not so much about air as about time. For high transfer efficiency, air restriction is necessary 1) to control the rate of combustion, and 2) to slow down the flames. The slower the flames and hot gasses are travelling through the stove, the longer they stay in the stove and more heat they will release, and the higher the heat transfer efficiency will be.

 

[Martin Strand III]

To look at this another way, IF the firebox temp is around 1100* F and the surface temp of your stove shows 500* F, or so, the difference is going up and out your chimney!

There's only two possibilities: either it's going up the chimney, or it's being stored in the significant mass of the stove's materials (metal, firebrick, whatever), which are capable of storing quote a few btus. This is the heat transfer efficiency. From what I can see, it varies greatly from stove to stove, much more so than the combustion efficiency. It really has to do with the flame path, and how exposed it is directly to the outside surfaces of the stove.

I happen to own two stoves which both have very good combustion efficiency, but which pretty much bracket the extremes of heat transfer efficiency. The Morso 2110's is fairly low, because the flame path is shorter and it has internal baffles which almost completely cover the flame path. The Quad 2100's is amazingly high, with a long, almost entirely exposed flame path. I'd guess there's a 15-20% difference between the two. Under normal operation, there's 100F difference in stack temps between them.

Granted, newer Phase II stoves and those with catalytic combustion add-ons do get more heat out of burning wood than older pre-Phase II stoves, they all (metal stoves) require restriction of incoming air which means there is more waste of potential heat from the fuel compared to a design where the fuel could be burned without incoming air restriction.

It's not so much about air as about time. For high transfer efficiency, air restriction is necessary 1) to control the rate of combustion, and 2) to slow down the flames. The slower the flames and hot gasses are travelling through the stove, the longer they stay in the stove and more heat they will release, and the higher the heat transfer efficiency will be.

Sorry, metal stoves aren't heralded for their thermal mass heat storage properties. In fact, they behave just the opposite.

Also, you seem to think "high" heat transfer properties are a good thing. For the application of heating a room with humans, this is not so. "Moderate" heat transfer properties of a stove is much kinder to occupants, results in less "indoor weather" (hot/cold cycling) and fried dust to breath. However, this desired propertyof moderate heat transfer is not possible with the predominant material from which metal stoves are constructed (read metal has to act like metal; it cannot act like stone).

Aye,
Marty

 

[precaud]

Sorry, metal stoves aren't heralded for their thermal mass heat storage properties. In fact, they behave just the opposite.

Then I'd like you to come here and move my stove without gloves several hours after the flames have died. You're making it sound like nothing is stored. Sure, masonry materials (brick, stone, whatever) have higher heat storage. But that's because they reject (reflect) more of it to begin with. They are basically resistive elements in the whole event.

Also, you seem to think "high" heat transfer properties are a good thing. For the application of heating a room with humans, this is not so. "Moderate" heat transfer properties of a stove is much kinder to occupants, results in less "indoor weather" (hot/cold cycling) and fried dust to breath. However, this desired propertyof moderate heat transfer is not possible with the predominant material from which metal stoves are constructed (read metal has to act like metal; it cannot act like stone).

A minute ago you were complaining about all the heat being lost up the chimney. Now you're saying high heat transfer isn't a good thing. Methinks you're just arguing for argument's sake. Have fun. I'm done.

 

[Martin Strand III]

Misuse of terminology is common and many simply don't understand the terms which rather easily explain difficulties communicating from "the same page".

Also, differences of opinion are not in themselves "arguments".

Combustion efficiency is a measurement of how much of the fuels chemical energy is released during the burn. I am not going to debate the elemental truth that wood burns more optimally at 1100* F, thus releasing more stored chemical energy than at 600* F.

Heat transfer efficiency is a measurement of how well an appliance delivers the released energy to your living quarters vs up and out the chimney. Metal has high heat transfer properties which is of benefit for more rapidly heating an area from a cold start but, unless restrained by decreasing its air intake, will overheat the living area or overfire the appliance. When air is thus restricted, combustion efficiency suffers.

Hope that helps.

Aye,
Marty

 

[stoveguy2esw]

here we go again....<sigh>

 

[stoveguy2esw]

Not so fast, Pvt Johnson.

SGC has (re)discovered what I've been lamenting about for some time (very old post of mine: "The Dichotomy of Burning Wood in a Metal Stove").

While I agree that temperature in the firebox may reach 1100* F and show a surface temperature of less, the amount less has been empiracle (read anybody's guess), it does this not as the rule but as the exception since a metal stove has to restrict incoming air to prevent over firing, thus be "dialed down", thus not be optimal burn temperature for burning wood fuel.

To look at this another way, IF the firebox temp is around 1100* F and the surface temp of your stove shows 500* F, or so, the difference is going up and out your chimney!

Granted, newer Phase II stoves and those with catalytic combustion add-ons do get more heat out of burning wood than older pre-Phase II stoves, they all (metal stoves) require restriction of incoming air which means there is more waste of potential heat from the fuel compared to a design where the fuel could be burned without incoming air restriction.

Aye,
Marty

are you saying that in a non-metal stove this heat is not going up the chimney?
also, second question, if air is allowed in without restriction , would not the same amount of air have to leave? if so wouldnt that unrestricted air take with it more of the heat produced? the fire would be much hotter , albiet uncontrolled, but the wood would be burned up in a fraction of the time and heat would simply leave through the flue before it was able to transfer into the body of the stove.

its true that different materials absorb and conduct heat at different rates, stone seems to take longer to heat up, but stays hot longer, steel conducts faster and therefore cools quicker but looking at skin temps does not tell the whole story. what we need in here is one of the guys at omni , or warnock hersey, they could explain this out better than i could.

 

[wg_bent]

A peice of the equation in the "stoves" ability to absorb heat is the path length for the appliance to absorb the heat. In the case of Marty's Tempcast, the path for the appliance to absorb heat is like 20' (a guess) so the fact that the heat transfer ability of th e material is lower requires that the surface area in the form of path length is essential to the efficiency. In a metal stove that's run 24/7 the stove can absorb just so much heat, then begins to push it up the chimney since there is no more it can absorb, and no ability to transfer it since it can't be 1100 degrees.

In the end, a 24/7 run stove must be pushing more total btu's up the chimney than the masonry heater.

 

[precaud]

A peice of the equation in the "stoves" ability to absorb heat is the path length for the appliance to absorb the heat. In the case of Marty's Tempcast, the path for the appliance to absorb heat is like 20' (a guess) so the fact that the heat transfer ability of th e material is lower requires that the surface area in the form of path length is essential to the efficiency.

Yes, path length is an important part of the equation. And masonry stoves exploit that to the max. But that doesn't allow completely false statements such as:

Metal has high heat transfer properties which is of benefit for more rapidly heating an area from a cold start but, unless restrained by decreasing its air intake, will overheat the living area or overfire the appliance. When air is thus restricted, combustion efficiency suffers.

This is a belief made to sound like a fact. But it's not true. And every metal stove on the planet that meets EPA emissions spec is living proof of it.

 

[DoubleClutch]

There's only two possibilities: either it's going up the chimney, or it's being stored in the significant mass of the stove's materials

What about the heat that goes into the air (and the walls, ceiling, floor, furniture...) of the house? Isn't that the point of having a stove in the first place?

 

[wg_bent]

A peice of the equation in the "stoves" ability to absorb heat is the path length for the appliance to absorb the heat. In the case of Marty's Tempcast, the path for the appliance to absorb heat is like 20' (a guess) so the fact that the heat transfer ability of th e material is lower requires that the surface area in the form of path length is essential to the efficiency.

Yes, path length is an important part of the equation. And masonry stoves exploit that to the max. But that doesn't allow completely false statements such as:

Metal has high heat transfer properties which is of benefit for more rapidly heating an area from a cold start but, unless restrained by decreasing its air intake, will overheat the living area or overfire the appliance. When air is thus restricted, combustion efficiency suffers.

This is a belief made to sound like a fact. But it's not true. And every metal stove on the planet that meets EPA emissions spec is living proof of it.

Agreed, not sure what to do with that quote. A couple problems there.

 

[Roospike]

Misuse of terminology is common and many simply don't understand the terms which rather easily explain difficulties communicating from "the same page".

Also, differences of opinion are not in themselves "arguments".

Combustion efficiency is a measurement of how much of the fuels chemical energy is released during the burn. I am not going to debate the elemental truth that wood burns more optimally at 1100* F, thus releasing more stored chemical energy than at 600* F.

Heat transfer efficiency is a measurement of how well an appliance delivers the released energy to your living quarters vs up and out the chimney. Metal has high heat transfer properties which is of benefit for more rapidly heating an area from a cold start but, unless restrained by decreasing its air intake, will overheat the living area or overfire the appliance. When air is thus restricted, combustion efficiency suffers.

Hope that helps.

Aye,
Marty

So why and how does it suffer ?
The best efficiency you can get on average for a wide open burning log is 50% efficiency , when air is lowered as per cat and or non cat stove the stoves efficiency is is in the 70%-80% range. and how does it change the heat transfer efficiency on a lower setting? ( tho your talking about combustion efficiency in the Heat transfer efficiency paragraph. )

 

[Roospike]

Not so fast, Pvt Johnson.

SGC has (re)discovered what I've been lamenting about for some time (very old post of mine: "The Dichotomy of Burning Wood in a Metal Stove").

While I agree that temperature in the firebox may reach 1100* F and show a surface temperature of less, the amount less has been empiracle (read anybody's guess), it does this not as the rule but as the exception since a metal stove has to restrict incoming air to prevent over firing, thus be "dialed down", thus not be optimal burn temperature for burning wood fuel.

To look at this another way, IF the firebox temp is around 1100* F and the surface temp of your stove shows 500* F, or so, the difference is going up and out your chimney!

Granted, newer Phase II stoves and those with catalytic combustion add-ons do get more heat out of burning wood than older pre-Phase II stoves, they all (metal stoves) require restriction of incoming air which means there is more waste of potential heat from the fuel compared to a design where the fuel could be burned without incoming air restriction.

Aye,
Marty

I guess you can enlighten us on how this works out if your statement is true.

When a woods stove is burning and the stove is say 500° and the secondary combustion is 1400° as it would be on a secondary burn chamber and the chimney exhaust temp is 400° then what happened to that 1400° temp you say that was wasted and went up the stack ?

An EPA II stove being 75% efficient then one will loose 25%. a pre EPA stove being 40% efficent you loose 60% , this is also the difference you gain from the secondary combustion EPA stove of the same like and kind steel box. (as per the thread question being asked )

Marty , me thinks your just being the “National Inquirer” of wood heat , take a little tid bit of information , twist it all around and blow out of proportion.

 

[Martin Strand III]

Guyz:

Lots of fodder to ruminate. I'll do so and be back.

Aye,
Marty

 

[Roospike]

Guyz:

Lots of fodder to ruminate. I'll do so and be back.

Aye,
Marty

We'll be here ya ole' goat.

 

[Martin Strand III]

Guyz:

Lots of fodder to ruminate. I'll do so and be back.

Aye,
Marty

We'll be here ya ole' goat.

Sorry, I took so long.

I've attempted to address your questions and to correct misconceptions in your previous posts in this thread. I have found material which supports my above posted statements and which I stand behind with the caveat that I do not have all the answers. Being challenged on concepts I have held as valid is a learning experience for me I welcome with an open mind.

So, here we go...

ABOUT “EFFICIENCY” (Attn: Precaud, Roo)

“Heating efficiency shows how rapidly the heat produced by the fire is transferred to the room. It does not, however, measure how comfortable the room will be, only how quickly the heat is delivered. A combination of high combustion efficiency and moderate heat transfer efficiency is the ideal in any wood burner.

Metal stoves and wood furnaces typically have relatively lower combustion efficiencies and relatively higher heat transfer efficiencies ... Metal transmits heat very well, in fact within minutes of the fire being lit. Similarly, the wood furnace heats the air instantly and immediately distributes this hot air to the home. This makes for a very responsive heater, which is able to throw heat into a space very quickly. However, this fast response comes with two critical drawbacks.

Firstly, it becomes very difficult to regulate the heat output so that it is comfortable. If the heat output (heat transfer) is controlled by restricting the air supply, combustion efficiency drops off drastically, causing a smoky fire, huge amounts of air pollution and probably creosote deposits. If the air supply is not restricted, combustion efficiency improves but the room becomes too hot and dry, which also has an adverse effect on the health of the occupants. This clearly demonstrates that high heat transfer efficiency is not a desirable quality in a wood heater.

Secondly, combustion efficiencies of metal stoves and furnaces are comparatively low, because the heat is given off too quickly and the temperature of the fire cannot build to the point where the gases are fully burned. Most metal stoves and furnaces cannot be burned safely over 900 degrees F. (482 deg. C) because the metal becomes too hot and the unit is severely "over-fired". They are usually not comfortable to be around when burned at over 400 degrees F. (204 deg. C), due to their high heat transfer efficiency.”

www.tempcast.com/planningguide/plan01.html
_______________________________________

ABOUT EFFICIENCY AND THERMAL MASS (Attn: Precaud, Stoveguy2, Roo)

“Heat transfer efficiency (thermal efficiency). How much of the heat generated in the firebox escapes through the chimney into the atmosphere (stack loss) depends on the firing strategy and the thermal mass of the heater. Newer metal stoves and fireplace inserts with firebrick lining are designed to be clean burning but still have poor thermal efficiency because they lack a thermal mass that functions as a heat exchanger. “

www.hotrockmasonry.com/PDFs/Planning_Guide.pdf
_________________________________________________

and

“Heating efficiency of any wood heater depends on 2 factors:
(1) Combustion Efficiency - how completely it burns the wood and
(2) Transfer Efficiency - how much of the fire’s heat gets into the room rather than going up the flue.

How efficient your wood heater operates depends on 2 more factors:
(1) Installation - location on outside v inside wall. Heater too big for house? Flue draw?
(2) Operation - Is wood green? Firebox load? Adequate air?

Your operating technique accounts for the largest variations in your woodstove’s heating efficiency.

[Unless you burn consistently above 1000* F] most of your [$$] investment in wood goes up in smoke.”

www.baaqmd.gov “Woodburning Handbook”
____________________________________________

ABOUT AIR RESTRICTION (Attn Roo)

“Wood needs 200% - 300% excess air [above required for chemical conversions], or complete combustion will be hard toachieve...”

All Fuels Expo, 1996, Burlington, VT
“Course in Heating Systems” by Norbert Senf
__________________________

Hope this helps.

Aye,
Marty

 

[Roospike]

Guyz:

Lots of fodder to ruminate. I'll do so and be back.

Aye,
Marty

We'll be here ya ole' goat.

Sorry, I took so long.

I've attempted to address your questions and to correct misconceptions in your previous posts in this thread. I have found material which supports my above posted statements and which I stand behind with the caveat that I do not have all the answers. Being challenged on concepts I have held as valid is a learning experience for me I welcome with an open mind.

So, here we go...

ABOUT “EFFICIENCY” (Attn: Precaud, Roo)

“Heating efficiency shows how rapidly the heat produced by the fire is transferred to the room. It does not, however, measure how comfortable the room will be, only how quickly the heat is delivered. A combination of high combustion efficiency and moderate heat transfer efficiency is the ideal in any wood burner.

Metal stoves and wood furnaces typically have relatively lower combustion efficiencies and relatively higher heat transfer efficiencies ... Metal transmits heat very well, in fact within minutes of the fire being lit. Similarly, the wood furnace heats the air instantly and immediately distributes this hot air to the home. This makes for a very responsive heater, which is able to throw heat into a space very quickly. However, this fast response comes with two critical drawbacks.

Firstly, it becomes very difficult to regulate the heat output so that it is comfortable. If the heat output (heat transfer) is controlled by restricting the air supply, combustion efficiency drops off drastically, causing a smoky fire, huge amounts of air pollution and probably creosote deposits. If the air supply is not restricted, combustion efficiency improves but the room becomes too hot and dry, which also has an adverse effect on the health of the occupants. This clearly demonstrates that high heat transfer efficiency is not a desirable quality in a wood heater.

Well said ( or quoted ) Thats is a great job of describing how a 55 GALLON BARREL STOVE works and with that i totally agree. Again with taking information and twisting it around and blowing out of scale. unfortunately a modern EPA wood stove that is worth a salt is NOT going to work like the old fashion barrel stove and characteristic as you describe.

Secondly, combustion efficiencies of metal stoves and furnaces are comparatively low, because the heat is given off too quickly and the temperature of the fire cannot build to the point where the gases are fully burned. Most metal stoves and furnaces cannot be burned safely over 900 degrees F. (482 deg. C) because the metal becomes too hot and the unit is severely "over-fired". They are usually not comfortable to be around when burned at over 400 degrees F. (204 deg. C), due to their high heat transfer efficiency.”

Again , Old data and information on an ole barrel style stove the modern EPA stoves run higher and hotter temps inside the fire box even as you had stated of 1100° - 1400° with secondary combustion , the placement of steel baffles , modern firebricks , heat blankets , boards and heat baffles keep the inside firebox and combustion chamber hot and takes the wood burning 50% efficiency up to 74% - 80% through secondary combustion.

Now Marty if "YOU" would just bring "YOURSELF" up to speed and information with modern EPA wood stoves and how they work you would have a better understanding of what everybody is talking about. You debating technology from 50 years ago of steel stoves on a forum of newer modern EPA stoves is kinda of pointless and misleading.

www.tempcast.com/planningguide/plan01.html
________

ABOUT EFFICIENCY AND THERMAL MASS (Attn: Precaud, Stoveguy2, Roo)

“Heat transfer efficiency (thermal efficiency). How much of the heat generated in the firebox escapes through the chimney into the atmosphere (stack loss) depends on the firing strategy and the thermal mass of the heater. Newer metal stoves and fireplace inserts with firebrick lining are designed to be clean burning but still have poor thermal efficiency because they lack a thermal mass that functions as a heat exchanger. “

www.hotrockmasonry.com/PDFs/Planning_Guide.pdf
____________

and

“Heating efficiency of any wood heater depends on 2 factors:
(1) Combustion Efficiency - how completely it burns the wood and
(2) Transfer Efficiency - how much of the fire’s heat gets into the room rather than going up the flue.

How efficient your wood heater operates depends on 2 more factors:
(1) Installation - location on outside v inside wall. Heater too big for house? Flue draw?
(2) Operation - Is wood green? Firebox load? Adequate air?

Your operating technique accounts for the largest variations in your woodstove’s heating efficiency.

[Unless you burn consistently above 1000* F] most of your [$$] investment in wood goes up in smoke.”

www.baaqmd.gov “Woodburning Handbook”
____________

ABOUT AIR RESTRICTION (Attn Roo)

“Wood needs 200% - 300% excess air [above required for chemical conversions], or complete combustion will be hard toachieve...”

All Fuels Expo, 1996, Burlington, VT
“Course in Heating Systems” by Norbert Senf
__________

Hope this helps.

Aye,
Marty

 

[Martin Strand III]

Hi Roo:

Sorry you didn't read the part that mentioned "Newer metal stoves" but, that's OK. I didn't see "55 Gal barrel stoves" anywhere in my post.

I'm curious how much (%) of a typical burn cycle in a typical modern wood stove falls within that 1100* F - 1400* F, or so, temperature range you mentioned these modern stoves burn at? My understanding is almost 20% of the burn in start up with kindling is the smokiest and dirtiest and for the cool down, especially those long 'overnight' heavily packed load stretches when you 'dial down' just before bedtime, who knows how much time the temp is under your optimal range?

And, for cat owners, how much of the burn are you "efficiently" using your converter?

Again, "[Unless you burn consistently above 1000* F] most of your [$$] investment in wood goes up in smoke.”

Not trying to knock metal stoves as they are (much improved from old and that's not sooo long ago), just attempting to show their limitations to spark technology improvements. But that's another topic*.

Aye,
Marty

* "There has been little incentive to increase the thermal efficiency of wood stoves ... due to economic considerations." (OMNI Environmental Services, Beaverton, OR, December 1998)
How are cordwood stove sales in the last 10 years compared to the decade before that?
(Sales for '97 were 1/2 the '90 level)

 

[precaud]

I'll try not to duplicate ground covered by Roospike already.
Marty, you've got to separate the marketing koolaide out from the "science" in these quotes.

A combination of high combustion efficiency and moderate heat transfer efficiency is the ideal in any wood burner.

Sure, a masonry stove maker would say something like that, because they have NO HOPE of ever achieving high heat transfer efficiency! They'd love you to believe that high transfer efficiency doesn't matter. The answer to that is obvious.

Metal stoves and wood furnaces typically have relatively lower combustion efficiencies and relatively higher heat transfer efficiencies ...

BS. It's the other way around. Combustion efficiency is quite high in every EPA-compliant stove sold. Transfer efficiency varies MUCH MORE from model to model.

Firstly, it becomes very difficult to regulate the heat output so that it is comfortable.

That's news to me. I have no problem doing so.

If the heat output (heat transfer) is controlled by restricting the air supply, combustion efficiency drops off drastically, causing a smoky fire, huge amounts of air pollution and probably creosote deposits. If the air supply is not restricted, combustion efficiency improves but the room becomes too hot and dry, which also has an adverse effect on the health of the occupants. This clearly demonstrates that high heat transfer efficiency is not a desirable quality in a wood heater.

Ummm, NO... this clearly demonstrates how out of touch with stove design for the last 25 years the author is.

“Heat transfer efficiency (thermal efficiency). How much of the heat generated in the firebox escapes through the chimney into the atmosphere (stack loss) depends on the firing strategy and the thermal mass of the heater.

Not true. Too general. All thermal masses are not the same.

Newer metal stoves and fireplace inserts with firebrick lining are designed to be clean burning but still have poor thermal efficiency because they lack a thermal mass that functions as a heat exchanger. “

Wait a minute! One paragraph up you were arguing that metal stoves had TOO HIGH a heat transfer! I think that you are not really thinking for yourself and are only parroting quotes that back up your conviction. Let's have some of YOUR thoughts and experience. With details.

 

[Martin Strand III]

Precau:

I haven't seen anything of substance here to influence me to make any changes in how I see the matters. "Gut" feelings simply don't cut it.

My words are clear in my previous posts. I have (unlike many) backed up my statements with references. You don't agree with what you read? Move on...

What you are quoting and quibbling about are not my words. I'm just the messanger here...

Aye,
Marty

 

[precaud]

This is no fun. You're 'way off base and got picked off but don't even know it. Bye Marty. You can discuss this with yourself.

 

[Martin Strand III]

This is no fun. You're 'way off base and got picked off but don't even know it. Bye Marty. You can discuss this with yourself.

Ah, it's always easier to slam the door and walk away...

Another wasted opportunity...

Aye,
Marty