# Wood burner fan



## gregmcateer (11 Feb 2021)

Good people of knowledge-ville,

Wondered if any here have experience of heat powered fans that sit atop yer wood burner, supposed to push the heat into the room.
Good / bad? Any particular brand?
TIA 
Greg


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## Blackswanwood (11 Feb 2021)

We have an Ecofan which is six years old and still going strong.

It definitely makes a positive difference.


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## Jacob (11 Feb 2021)

Can't possibly make a difference. It just vaguely redirects a tiny fraction of the heat from the top of the stove, but looks convincing.
Google - "Do eco fans work?
Unfortunately no, the Ecofan generates its own electricity through temperature differential. The base must make contact with a heat source of at least 85°C and the top of the fan must remain cooler. The Ecofan needs to draw cooler air from behind in order to operate."


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## gregmcateer (11 Feb 2021)

Hmmm. So that's two sides of the equation. Thank you gents for your input. 
Any others wanna wade in?


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## Blackswanwood (11 Feb 2021)

I don’t care what Google says ... I’m sat watching mine and feeling the benefit now!


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## porker (11 Feb 2021)

Have to disagree with Jacob - we have a couple of woodburners. One is in a tighter alcove than the other and we ran it without for a few weeks before we got one. After getting it, the heat distribution was much more even in the room. True they don't shift vast volumes of air but it is enough to make it worthwhile on ours. Ours is only a cheapy but still going 4 years on. The only slightly annoying thing it does is make a bit of noise when the bi-metalic strip on the base lifts it off the stove when the heat reaches a certain point but it is very minor. The fan itself is silent.


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## Jacob (11 Feb 2021)

porker said:


> Have to disagree with Jacob - we have a couple of woodburners. One is in a tighter alcove than the other and we ran it without for a few weeks before we got one. After getting it, the heat distribution was much more even in the room. True they don't shift vast volumes of air but it is enough to make it worthwhile on ours. Ours is only a cheapy but still going 4 years on. The only slightly annoying thing it does is make a bit of noise when the bi-metalic strip on the base lifts it off the stove when the heat reaches a certain point but it is very minor. The fan itself is silent.


Well yes they may redirect a tiny bit of air but you don't get anything for nothing. Have you tried a smoke test - light an incense stick or something and watch how the air comes and goes?


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## Peterm1000 (11 Feb 2021)

I have a Vonhaus 3 blade one. It spins and moves so little air you can hold a piece of loo paper in front of it and it barely moves. Total waste of money. I think it might be a case of you get what you pay for because one I saw in a showroom definitely moved the air.


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## Phil Pascoe (11 Feb 2021)

We had an Aldi cheapo because my loved one thought they were a good idea. They don't push anything like enough air to actually achieve anything.


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## Sandyn (11 Feb 2021)

A comparison of some here


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## stuartpaul (11 Feb 2021)

Ours definitely makes a difference, you can feel it moving a reasonable amount of air and heat distribution in the room has certainly improved.


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## Richard_C (11 Feb 2021)

I have one and it works fine. Stove is wholly set back in a brick alcove fireplace and it moves the air enough to warm the room more quickly. It doesn't project it far, just enough stirring to move some out from under the lintel. If the stove stood out further and had good natural convection I wouldn't use one.


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## artie (12 Feb 2021)

I've had a 5 blade one since 2018.

My stove is in an alcove so it helps to circulate the air. It's a smallish living room but the effect can be felt, but very slight.


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## Robbo3 (12 Feb 2021)

Had so little effect in my draughty concrete panel workshop that I gave it to a brother in law who thinks it's brilliant.


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## glenfield2 (12 Feb 2021)

A lot of people (including us) have them on narrowboats and say they work well. We also have one in our kitchen at home and I’m less convinced. The room is too oddly shaped. I think the effect is slight but effective in certain sorts of spaces where there’s a simple pattern of airflow.


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## gregmcateer (12 Feb 2021)

Thanks for all the input, folks. Looks like it may be worth it if you spend a decent amount, but don't bother with a cheapo
Cheers


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## Jacob (12 Feb 2021)

glenfield2 said:


> A lot of people (including us) have them on narrowboats and say they work well. We also have one in our kitchen at home and I’m less convinced. The room is too oddly shaped. I think the effect is slight but effective in certain sorts of spaces where there’s a simple pattern of airflow.


I suppose it makes some sense in the room shape of a narrow boat. Some of the heat will get wafted through the boat instead of dissipating through the uninsulated roof area near the stove


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## Woody2Shoes (12 Feb 2021)

As is obvious when you open the door, most of the heat is emitted by convection rather than radiation. If the stove has been installed to allow a free flow of air all around it, then my experience is that a fan is fun but makes little difference - except perhaps in helping to de-stratify the air in the room a little (which may make the room feel a little warmer, quicker).
My observations are based on cast iron stoves with firebricks, which burn more efficiently (and therefore cleaner) but probably get up to a full convection temperature externally more slowly as a result - making the small effect of the fan slightly more noticeable than otherwise.


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## Jacob (12 Feb 2021)

Woody2Shoes said:


> As is obvious when you open the door, most of the heat is emitted by convection rather than radiation. If the stove has been installed to allow a free flow of air all around it, then my experience is that a fan is fun but makes little difference - except perhaps in helping to de-stratify the air in the room a little (which may make the room feel a little warmer, quicker).
> My observations are based on cast iron stoves with firebricks, which burn more efficiently (and therefore cleaner) but probably get up to a full convection temperature externally more slowly as a result - making the small effect of the fan slightly more noticeable than otherwise.


Why do you thing cast iron and firebricks is more efficient?
I've got sheet steel stoves and they produce heat cleanly and much quicker than the various firebrick/steel/cast iron versions I've had in the past. Also are maintenance free and cheaper to run.


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## Phil Pascoe (12 Feb 2021)

^^^ There's far less soot from my Dowling than there was from my old Clearview (nice stove though it was). 






Dowling Stoves - Home


Dowling Stoves, hand-crafted in Scotland - Strongest in the World



www.dowlingstoves.com


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## Phil Pascoe (12 Feb 2021)

I've just agreed with Jacob ............ I've come over all unnnecessary ...........


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## Jacob (12 Feb 2021)

I used to replace some/all firebricks on my picturesque Morso Squirrel every year, and the cast iron baffle quite often too. Probably added 25% on top of the fuel cost. Also it'd take much longer to heat up.


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## Jacob (12 Feb 2021)

Phil Pascoe said:


> I've just agreed with Jacob ............ I've come over all unnnecessary ...........


Don't worry about it Phil, everybody agrees with me in the end!


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## Phil Pascoe (12 Feb 2021)

Jacob said:


> I used to replace some/all firebricks on my picturesque Morso Squirrel every year, and the cast iron baffle quite often too. Probably added 25% on top of the fuel cost. Also it'd take much longer to heat up.


My Clearview worked out at £400 over every three years.


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## Phil Pascoe (12 Feb 2021)

Jacob said:


> Don't worry about it Phil, everybody agrees with me in the end!


I worry more when they agree with you in the beginning.


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## Droogs (12 Feb 2021)

All I know is as the woodstove is the only source of heat in my gaff at this time, if the fan is on top of it and points towards SWMBO, my ears get a rest from how bloody cold it is. So yeah they are absolutely worth it


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## Sandyn (12 Feb 2021)

I have never felt the need for any additional air circulation with my multi-fuel stove, but it's not recessed. When I pre-installed it, I drilled a hole through the wall below and behind the stove for the air intake. The alternative was a vent above the door, but that would have caused a cold draft coming from behind the seats.


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## artie (12 Feb 2021)

Sandyn said:


> I have never felt the need for any additional air circulation with my multi-fuel stove, but it's not recessed. When I pre-installed it, I drilled a hole through the wall below and behind the stove for the air intake. The alternative was a vent above the door, but that would have caused a cold draft coming from behind the seats.


I piped in the cold air from outside for mine. There is a fitting on the bottom of the stove to attach it to.
No draughts and sitting here at 11:36 having my coffee, RH is 35% the stove hasn't been lit since last night


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## Blackswanwood (12 Feb 2021)




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## Jameshow (12 Feb 2021)

Jacob said:


> Why do you thing cast iron and firebricks is more efficient?
> I've got sheet steel stoves and they produce heat cleanly and much quicker than the various firebrick/steel/cast iron versions I've had in the past. Also are maintenance free and cheaper to run.


Over the past 20 years I've had three stoves 

A dursley highlander 5 (steel) 

2nd house 
Nestor Martin 23 (cast iron)

The Nestor Martin was so bad we replaced it with a Ottowa 12 stove off eBay. (Steel)

Which is far quicker to heat up, burns better, stays clear, produces less ash and has a bigger ash pan. 

No competition despite the nestor Martin being a "high end stove" 

Cheers James


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## Woody2Shoes (12 Feb 2021)

Jacob said:


> Why do you thing cast iron and firebricks is more efficient?
> I've got sheet steel stoves and they produce heat cleanly and much quicker than the various firebrick/steel/cast iron versions I've had in the past. Also are maintenance free and cheaper to run.


I knew you'd say that Jacob, because you mentioned your preference a while back on another thread!

Fire bricks concentrate the heat so that the wood reaches, and stays at, a high temperature while it's burning - this is vital to minimise smoke/tar production. If you look at all the stoves which are certified for use in a smoke control area or are "ready" for the more strict eco rules (the name of which I can't remember and can't be bothered to google), they all have fire bricks or an equivalent thermal "nest" for efficient combustion - simply because achieving certification would be nigh on impossible without them.

I think that as far as cast iron is concerned, there's less of an efficiency argument - more of a thermal mass argument in favour of stable operating temperatures.

Cheers, W2S


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## Woody2Shoes (12 Feb 2021)

Jacob said:


> I used to replace some/all firebricks on my picturesque Morso Squirrel every year, and the cast iron baffle quite often too. Probably added 25% on top of the fuel cost. Also it'd take much longer to heat up.


I think you've been doing something wrong. All my (three) stoves are Morsos, but not Squirrels, and are used daily for several months a year. I've been through two sets of firebricks in twenty years!


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## Woody2Shoes (12 Feb 2021)

Jameshow said:


> Over the past 20 years I've had three stoves
> 
> A dursley highlander 5 (steel)
> 
> ...


I note from the sales description that the Ottawa 12 has both fire bricks and a cast iron backplate. I rest my case, m'lud...


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## Jacob (12 Feb 2021)

Woody2Shoes said:


> I think you've been doing something wrong. All my (three) stoves are Morsos, but not Squirrels, and are used daily for several months a year. I've been through two sets of firebricks in twenty years!


Followed directions fairly carefully as far as I recal.
Do you burn solid fuel? I did and don't think the stove was durable enough - bricks would crumble etc. 
Probably a lot better (for the stove) to just burn wood, but then you need a much bigger stove to get enough heat out.


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## Woody2Shoes (12 Feb 2021)

Jacob said:


> Followed directions fairly carefully as far as I recal.
> Do you burn solid fuel? I did and don't think the stove was durable enough - bricks would crumble etc.
> Probably a lot better (for the stove) to just burn wood, but then you need a much bigger stove to get enough heat out.


I sometimes burn anthracite, but I find it is more chemically agressive and it stains the glass - normally just dry hardwood (oak/ash/beech/hawthorn etc.). Anthracite normally reserved for the Rayburn, which is multifuel, but keeping that fed with wood instead would leave me with no time for much else!


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## stevek (12 Feb 2021)

A very intresting post, esp the video, we have a Workzone fan (Aldi) and its two bladed, sitting on top of our Jotal cast iron stove, and I really cannot feel or detect anything in the way of draught when its running, I tried smoke but of course the heat from the stove just carries it up and holding a thin strip of tissue paper in front of it doesnt really result in anything like air movement, we still use it but I was not convinced it worked strongly enough to overcome the convection of the stove. Our stove sits in an inglenook fireplace so the idea of blowing air which would also draw and circulate air around the stove is attractive. What really intrested me was the fan that did not work,,it was spinning away just like the others so how would it not work? must be something to do with blade angles I would think,,might be worth experimenting. I have at various times thought about rigging up a small and quiet electric fan in the fireplace and seeing what effect that has, in fact thats the thing that might work best?
Steve.


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## Jacob (12 Feb 2021)

stevek said:


> .....I have at various times thought about rigging up a small and quiet electric fan in the fireplace and seeing what effect that has, in fact thats the thing that might work best?
> Steve.


Could work - cheaper to run than to buy a collection of Eco fans.
We had an old Turtle stove in a very big old fireplace and to make it work the chimney opening was well sealed and insulated (except for the pipe obviously) and there was a back panel tilting forwards to encourage air flow into the room. 
You can't get the turtles nowadays of course.


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## D_W (12 Feb 2021)

Jacob said:


> Followed directions fairly carefully as far as I recal.
> Do you burn solid fuel? I did and don't think the stove was durable enough - bricks would crumble etc.
> Probably a lot better (for the stove) to just burn wood, but then you need a much bigger stove to get enough heat out.



you need to line the brick due to oxidation if you're burning solid fuel. but better to burn solid fuel would be a stove explicitly designed for it. The multipurpose stoves generally aren't that great. 

We burned wood for about 12 years when I was a kid and then switched to all oil once oil was cheap in the late 80s. Both sets of grandparents burned oil and coal, with one changing to wood in retirement (because that grandparent started commercially cutting and delivering wood - he was farming prior running a fairly large operation and burned oil due to lack of time to keep up with wood or be at the house to stoke wood). 

At any rate, airtight stove - 3400 square feet of old stone house, 8 cords per year. That's a lot of wood, but for the house, not that much. No firebricks - the stove was welded steel, but very thick, we kept several inches of ashes in it rather than faffing with firebricks (same effect). 

The point of bricks in stoves is probably to keep the burn temp up as well at the bottom of the stove, but we didn't pay attention to that. Despite comments to the contrary here about heat distribution, we ran a fan at low speed near the stove else the house was relatively cold and very hot at the stove. Perhaps 80F or more in the side of the room the stove was on and 60F on the far side of the house (house was a 45 foot square with a circular run around it). 

Adding a low volume fan (probably only slightly more than the stove top powered stove) was well worth it. If I had a stove in an open area, I'd have one of those stove top fans - you only need small gradual movement to make a very large difference. The gradual push of the air around our "circle" in the downstairs of the house rose the far side temperature almost 10 degrees. And garnered comments from relatives "what kind of silly person uses a fan in the winter...do you need to cool down or something?"


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## Woody2Shoes (12 Feb 2021)

D_W said:


> ........
> 
> Adding a low volume fan (probably only slightly more than the stove top powered stove) was well worth it. If I had a stove in an open area, I'd have one of those stove top fans - you only need small gradual movement to make a very large difference. The gradual push of the air around our "circle" in the downstairs of the house rose the far side temperature almost 10 degrees. And garnered comments from relatives "what kind of silly person uses a fan in the winter...do you need to cool down or something?"
> .....


I think you were benefiting from the "de-stratification" effect I first mentioned. Most of the heat from a convector goes upwards - and tends to stay there (there can be a 5C+ difference in our sitting room between floor height and ceiling height) - stirring it up a bit does help (probably disproportionately if you study the psycho/phsyiological benefits of warmer feet!).

PS I read that some parts of the US mandate catalytic converters in flues to try and mitigate the air pollution (from burning conifers perhaps, or maybe from using inefficient, poorly designed stoves without airbricks!)


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## Woody2Shoes (12 Feb 2021)

stevek said:


> ..... I have at various times thought about rigging up a small and quiet electric fan in the fireplace and seeing what effect that has, in fact thats the thing that might work best?
> Steve.


A friend did exactly this - he used a fan from an ATX PSU. His stove was in a very confined space in what had been a fireplace intended for a gas fire - he thus got little or no convection around his stove, and the fan was a small help until the surrounding masonry started to warm up. I think that if your stove is installed to allow proper convection, then you would get less benefit from a fan - except perhaps from a de-stratifying effect.


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## Phil Pascoe (12 Feb 2021)

stevek said:


> A very intresting post, esp the video, we have a Workzone fan (Aldi) and its two bladed, sitting on top of our Jotal cast iron stove, and I really cannot feel or detect anything in the way of draught when its running ... I have at various times thought about rigging up a small and quiet electric fan in the fireplace and seeing what effect that has, in fact thats the thing that might work best?
> Steve.


 Ditto on the first point. We had a room that was two knocked into one, so the stove had to be a quarter of the way from either one end or the other because that was where the chimneys were. A twenty four foot room with nine foot ceilings. We put a ten inch desk fan on one side of the hearth at the front facing along the the room, and a four inch bathroom fan below the coving at the far end blowing out into the stairwell. In the winter it made a world of difference upstairs when left on for a long time - had we stayed in the house I'd have replaced the small fan with a six inch one.

I'm just in the process of putting an insulated six inch duct from a six inch fan in the ceiling a few feet from the stove to the kitchen and the bedroom. Got to be worth a go for a hundred quid or so.


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## stevek (12 Feb 2021)

Yes I had thought about computer fans because they are small and quiet but we have the room for a regular elect fan,,maybe one of those flat fan heaters could be tucked away somwhere? But Im intrigued by the fan that didnt work at all, fan spinning around but no air movement,,how is that? Clearly somthing to do with blade angles I guess? I bet there is something on the internet about propeller efficiency. It might also explain why the initial post resulted in lots of people saying how well they worked whilst others were certain they didn't work at all! 
Ref stratification, in hot climates they have those big ceiling fans, relativly slow moving, and they have a reversing switch, I cannot recall which is which but its one way in hot weather and the other in cold weather.
Steve.


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## MorrisWoodman12 (12 Feb 2021)

We had a new stove fitted a year ago. The top is a 6mm plate sitting on a few pegs to hold it up with little thermal connection to the main body presumably so it doesn't get too hot and therefore to be safe. Guess what! We have two fans on top: one hardly ever works while the other does when the fire is roaring.
Martin


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## Mick p (12 Feb 2021)

Jacob said:


> Can't possibly make a difference. It just vaguely redirects a tiny fraction of the heat from the top of the stove, but looks convincing.
> Google - "Do eco fans work?
> Unfortunately no, the Ecofan generates its own electricity through temperature differential. The base must make contact with a heat source of at least 85°C and the top of the fan must remain cooler. The Ecofan needs to draw cooler air from behind in order to operate."


They work fine on canal boats and do make a difference


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## artie (12 Feb 2021)

I dug out the anemometer this evening, well truth be told, I couldn't find it and had to wait till her indoors arrived home.

This is a regular occurrence when I am looking for something seldom used.

So after the usual pantomime of locating a suitable battery, with some power left in it, I tested air flow and was surprised to get a reading of 5.63 ft per sec.


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## Phil Pascoe (12 Feb 2021)

I altered the blade angle on mine - it might have made a difference, but still the airflow was insignificant.


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## D_W (12 Feb 2021)

artie said:


> I dug out the anemometer this evening, well truth be told, I couldn't find it and had to wait till her indoors arrived home.
> 
> This is a regular occurrence when I am looking for something seldom used.
> 
> So after the usual pantomime of locating a suitable battery, with some power left in it, I tested air flow and was surprised to get a reading of 5.63 ft per sec.



a drop of paraffin oil on a hot spoon will allow for smoke tracing airflow direction without much heat needed. Large volume of air at low speed is a nice combination for heating. Deceptively effective distribution and no dry eyes. 

Or you, could just break wind behind the fan and:
1) time delay until scrunch face
2) measure distance to halfway between last scrunch face and first person with no scrunch face


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## johnnyb (12 Feb 2021)

I've got a portway stove its welded steel with firebrick its blooming brilliant. I reckon its because its airtight the controls work superbly well allowing very tight control of the burn. the bottom vent is shut as soon as possible. the top vent burns the smoke. when your shut this vent and the flames start slowly shimmering blimey the heats amazing. many cheaper stoves are noticeably inferior.


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## johnnyb (12 Feb 2021)

that didn't come out right. what I meant was cheaper stoves aren't as well designed. ps mine was used off ebay. the bloke had a chimney fire (unlined) and his insurance paid for a new stove complete with liner!


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## Jacob (12 Feb 2021)

Mick p said:


> They work fine on canal boats and do make a difference


Well yes I did go on to say in a later post:
"I suppose it makes some sense in the room shape of a narrow boat. Some of the heat will get wafted through the boat instead of dissipating through the uninsulated roof area near the stove"


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## Jacob (12 Feb 2021)

artie said:


> .... I tested air flow and was surprised to get a reading of 5.63 ft per sec.


That's 1 on the Beaufort scale!


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## artie (12 Feb 2021)

Jacob said:


> That's 1 on the Beaufort scale!


I don't know what that means.


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## Jacob (12 Feb 2021)

artie said:


> I don't know what that means.











Beaufort scale - Wikipedia







en.wikipedia.org


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## D_W (12 Feb 2021)

Jacob said:


> .. will get wafted through the boat instead of dissipating..."



perfect words to be used with my test mentioned above. Wafting.


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## D_W (12 Feb 2021)

Woody2Shoes said:


> I think you were benefiting from the "de-stratification" effect I first mentioned. Most of the heat from a convector goes upwards - and tends to stay there (there can be a 5C+ difference in our sitting room between floor height and ceiling height) - stirring it up a bit does help (probably disproportionately if you study the psycho/phsyiological benefits of warmer feet!).
> 
> PS I read that some parts of the US mandate catalytic converters in flues to try and mitigate the air pollution (from burning conifers perhaps, or maybe from using inefficient, poorly designed stoves without airbricks!)



stove regs vary state by state. Our stove was a simple slow movement low-stack-temp stove. 70s technology. Most of the EPA approved stoves now have a secondary burn element and introduced air at the top of the firebox before allowing exhaust out. Gas is so cheap here (and I'm in a different type of area now - was rural, now suburban) that it's uncommon to smell a wood stove, even with 350 houses in the neighborhood. The neighborhood has a lot of woods area and 99% of the wood falls and rots. Our neighborhood association is begging people to bring their own chainsaws to the public land and take wood for free. 

At any rate, pine isn't commonly burned in my area because wood like cherry and red oak grow quickly (especially red oaks and pin oaks), split easily and dry well. That's all we burned in our house, and when we removed the stove, the creosote in the chimney expanded due to the fireplace temp (the stove had been in a huge stone fireplace and we insulated above the stove, so there was never any real stack temp). Chimney fire resulted. I'm guessing the secondary combustion is desired first for air quality purposes, and second as a request from insurers. 

But, we're out of the loop. Big stone hearth and a fireplace opening 5 feet wide describes what you mentioned about air movement earlier - the sides of the hearth would heat up, but the stove was trapped against the wall and it would do its job. It did its job better with the fan forcing new air to come in and sending warm air out. It was also on the opposite end of the room vs. the seating area - large room around 30 feet long - just not well set up to broadcast the heat out and the house originally had two more woodstoves installed, so likely never intended for that spot to supply heat to the house .

Ag extension here (university outposts) tells people not to burn any softwoods known to be pitchy or sappy, though my understanding is that the person who wants to do it can just run stack temp way up for half an hour or so a day and the chimney will remain dry and safe. My dad is so stingy, he never would've "wasted" the heat going up the chimney, thus we ended up with the fire department solution instead. We burned almost exclusively red oak, with walnut, cherry or locust once in a while. usually no bark (we either split it off or if we bought wood, it was from a relative who send wood with bark to "people in town who won't care")

Our stove wasn't an insert, though - it was a long-log stove - half stuck out of the fireplace, half in. About 36 inches long and would burn wood about 32 at the max. The selling point for a stove like that was that you could load it every 8 hours and still heat a large area. Pull the ashes to the front, put in the next load and shut down the air flow.


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## artie (13 Feb 2021)

I reckon 1 on the Beaufort scale is pretty good for an 8" fan.


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## DennisCA (13 Feb 2021)

Woody2Shoes said:


> I think you were benefiting from the "de-stratification" effect I first mentioned. Most of the heat from a convector goes upwards - and tends to stay there (there can be a 5C+ difference in our sitting room between floor height and ceiling height) - stirring it up a bit does help (probably disproportionately if you study the psycho/phsyiological benefits of warmer feet!).
> 
> PS I read that some parts of the US mandate catalytic converters in flues to try and mitigate the air pollution (from burning conifers perhaps, or maybe from using inefficient, poorly designed stoves without airbricks!)



I don't know what air bricks are, but burning softwoods is not a problem in an efficient stove that has secondary combustion of flue gasses. Still from my perspective, most normal stoves are inefficient and waste a lot of heat through the chimney or because they radiate most of it at once instead of accumulating it so you get large temperature swings. Though the secondary combustion at least mitigates the pollution issue.

The most efficient traditional wood burning designs in the world right now are modern masonry ovens of scandinavian design with passages for the smoke to pass through so the heat from the flue gasses can be mostly extracted before entering the chimney. They can be up to 90% efficient in retaining the heat, they often weigh several tonnes so they can retain the heat and you only need to fire them once or twice a day. 

After that we have reverse wood gasification boilers which are probably the most advanced wood burning technology out there and can go over 90% efficiency. Of course with those you don't use mass to retain the heat but water, so it requires a pretty advanced setup and you need 3-6 cubic meters of water ideally or you can't take advantage of it. But with that kind of setup you can keep a whole house and even a separate workshop heated through cold northern winter in Sweden or Finland and you only need to fire them every other or 3rd day.

We have a masonry heater with secondary air for total combustion and burn mostly softwood and the chimney sweep comes every 4-5 years because more often is pointless. When the fire gets going and you go out and look at the chimney you only see a heat haze.


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## glenfield2 (13 Feb 2021)

Jacob said:


> I suppose it makes some sense in the room shape of a narrow boat. Some of the heat will get wafted through the boat instead of dissipating through the uninsulated roof area near the stove


I agree with your first point - it’s a long narrow space but not your second: the average narrowboat is extremely well insulated throughout generally these days with Sprayfoam. Warmer than most houses in this weather!


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## glenfield2 (13 Feb 2021)

On the subject of which woodstove, we bought a cheap new one off eBay a couple of years ago which is brilliant. Easy to light, burns efficiently. Bought a near identical one from the same firm recently which apparently complies with the latest regulations whatever they are (three air inlets rather than two) and it’s b*ll*cks. Hard to light; has to run fast to keep going so burns more fuel - hardly planet saving emissions then.


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## Jacob (13 Feb 2021)

glenfield2 said:


> On the subject of which woodstove, we bought a cheap new one off eBay a couple of years ago which is brilliant. Easy to light, burns efficiently. Bought a near identical one from the same firm recently which apparently complies with the latest regulations whatever they are (three air inlets rather than two) and it’s b*ll*cks. Hard to light; has to run fast to keep going so burns more fuel - hardly planet saving emissions then.


Run small fire fast but stoke more often is efficient in terms of heat production, and cleaner, but inconvenient. It's a trade off.
I burn loadsa rubbish - off cuts, pallets, scrap furniture, sawdust and shavings, which can burn fast like a rocket stove and produce heat very quickly, but has to be fed often to do that. 
Big stove with small fire is efficient - plenty of air around the fire for faster burning and larger surface area to conduct heat into the room.
Re fans - this is a chapel conversion and part of it is full height about 24ft. Very well insulated roof, so wondered about bringing hot air back down with a fan and ducting. I wondered if anybody has done this.
I envisaged simply a 24' long box like a wooden organ pipe perhaps 10" square, open at the top near the ceiling, open at the bottom facing out with a fan in the opening.


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## DennisCA (13 Feb 2021)

Bringing heat down with fans is done and it's incredible the amount of heat that is wasted with high ceilings otherwise, almost criminal. In work environments with really high ceilings the difference is even starker. Can also be used as a way to save heat, if you need to open the doors turn off the fans and let it rise, then turn them back on when the doors close.


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## Woody2Shoes (13 Feb 2021)

DennisCA said:


> I don't know what air bricks are, but burning softwoods is not a problem in an efficient stove that has secondary combustion of flue gasses. Still from my perspective, most normal stoves are inefficient and waste a lot of heat through the chimney or because they radiate most of it at once instead of accumulating it so you get large temperature swings. Though the secondary combustion at least mitigates the pollution issue.
> 
> The most efficient traditional wood burning designs in the world right now are modern masonry ovens of scandinavian design with passages for the smoke to pass through so the heat from the flue gasses can be mostly extracted before entering the chimney. They can be up to 90% efficient in retaining the heat, they often weigh several tonnes so they can retain the heat and you only need to fire them once or twice a day.
> 
> ...


Sorry - meant fire not air bricks!

I was intrigued to watch this video:


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## Woody2Shoes (13 Feb 2021)

Jacob said:


> .....
> Re fans - this is a chapel conversion and part of it is full height about 24ft. Very well insulated roof, so wondered about bringing hot air back down with a fan and ducting. I wondered if anybody has done this.
> I envisaged simply a 24' long box like a wooden organ pipe perhaps 10" square, open at the top near the ceiling, open at the bottom facing out with a fan in the opening.


You might find it easier to push cooler air upwards - so it mixes with the warmer air and comes back down again (on the basis that what goes up must come down) - in effect, to encourage a vertical circulation and mixing of the air "strata" i.e. de-stratification.

I think the most common solution is "push down" e.g. A Guide To Destratification Heating and Benefits - Powrmatic
but I don't see why "push up" wouldn't work (as long as the room's not too draughty) and the benefit would be less visual clutter above your head.


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## Woody2Shoes (13 Feb 2021)

Woody2Shoes said:


> You might find it easier to push cooler air upwards - so it mixes with the warmer air and comes back down again (on the basis that what goes up must come down) - in effect, to encourage a vertical circulation and mixing of the air "strata" i.e. de-stratification.
> 
> I think the most common solution is "push down" e.g. A Guide To Destratification Heating and Benefits - Powrmatic
> but I don't see why "push up" wouldn't work (as long as the room's not too draughty) and the benefit would be less visual clutter above your head.


PS stratification is one of the reasons why under-floor heating is so popular - besides the cosy feeling of warm feet, the warmth comes up from below.


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## doctor Bob (13 Feb 2021)

My burner is 8kw rated, I have a little fan. It looks pretty not sure what it does. We get to hot and end up opening all doors. 
I go for a good burn and then put a massive log on and that does the evening


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## Jelly (13 Feb 2021)

Woody2Shoes said:


> Anthracite normally reserved for the Rayburn, which is multifuel, but keeping that fed with wood instead would leave me with no time for much else!



How do you find the Rayburn?

I've been offered one which needs an overhaul FOC if I can move it, and am tempted to take it on as a project as it would fit in with my (eventual) plans to replace the godawful fitted kitchen with a freestanding kitchen setup.

But whilst I've done a fair bit of research into the plumbing setup needed to use the back boiler (conclusion, I would likely remove and sell it because of the complexity of merging with my existing DHW CH system) I don't really know a great deal about the practicalities of living with one.


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## Jacob (13 Feb 2021)

Jelly said:


> How do you find the Rayburn?
> 
> I've been offered one which needs an overhaul FOC if I can move it, and am tempted to take it on as a project as it would fit in with my (eventual) plans to replace the godawful fitted kitchen with a freestanding kitchen setup.
> 
> But whilst I've done a fair bit of research into the plumbing setup needed to use the back boiler (conclusion, I would likely remove and sell it because of the complexity of merging with my existing DHW CH system) I don't really know a great deal about the practicalities of living with one.


They were a great improvement on the open fire range but superseded by gas or electric appliances about 100 years ago
I've had two. They are a disaster in terms of cooking unless you keep them lit permanently and spend a fortune on fuel. Even then you still need another cooker for when the Rayburn isn't up to temp, if you've been using it for a bit of cooking for instance.
They keep the kitchen nice and warm, whether or not you want it too.
There's just the odd cold wintry day when the seem like a good idea, especially if you've just come in from sledging, or fishing through a hole in an ice covered lake.


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## Ollie78 (13 Feb 2021)

Our £25 amazon fan makes a big difference. Before one room was super toasty but the kitchen was cold, now the entire downstairs gets warmed.
It just creates enough convection to make the air circulate.


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## Droogs (13 Feb 2021)

My ex's family home (a farmhouse) had a Raeburn multi fuel rather than the more common Aga. it had the back boiler and was hooked up to an underfloor heating system and was great for most of the time. The kitchen was always hot and the kettle always on. Was great for when the power went off (often in winter). It was a pig to empty and clean but great to cook with if you had it running all the time, especially for baking and casseroles. Still needed a normal cooker for in the summer as the raeburn would be too hot to have on. i dream of having one but only in the right type of house and only if it was built with the cooker range in mind


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## Jacob (13 Feb 2021)

Droogs said:


> ..... Was great for when the power went off (often in winter). ....


Which happens for about 10 minutes or so per year. If it really was a prob then a calor gas cooker would be better. In fact would be better even if power cuts weren't a problem!


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## Droogs (13 Feb 2021)

@Jacob their power would go off a couple of times a year, especially with weather like now or when a bad storm damaged the power cable and often for 4 or 5 days at a time not 10 minutes. Hence the reason they went to the expense of having the range with a back boiler hooked up to underfloor heating pipes. They also had an ex RAF 40KVA generator to give power for the farm machinery and lighting etc when it was off. This was only 20 years ago. Yes they are in a remoter part of the country but not that remote.


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## DennisCA (13 Feb 2021)

Woody2Shoes said:


> Sorry - meant fire not air bricks!
> 
> I was intrigued to watch this video:




Yeah that's a lot like a traditional masonry heater, only thing with those is they don't have any secondary air, all the air for combustion comes from below and passes through the fire, this lowers the efficiency of the combustion and so they don't get as much heat out of the wood, but thanks to the many channels the smoke passes through it's still quite effective.

edit:
The change to add secondary air is really astonishingly simple, this is my masonry heater, it has a slot infront of the firebox that draws fresh air, which passes infront of the fire and mixes with the flue gasses above the fire.


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## stevek (13 Feb 2021)

Woody2Shoes said:


> You might find it easier to push cooler air upwards - so it mixes with the warmer air and comes back down again (on the basis that what goes up must come down) - in effect, to encourage a vertical circulation and mixing of the air "strata" i.e. de-stratification.
> 
> I think the most common solution is "push down" e.g. A Guide To Destratification Heating and Benefits - Powrmatic
> but I don't see why "push up" wouldn't work (as long as the room's not too draughty) and the benefit would be less visual clutter above your head.


If he does decide to give a fan a go its worth bearing in mind that even the cheap B&Q ones had the reversing switches, so whatever direction is recommended you can just switch from one to the other,,a few years ago I was really surprised how cheap some of the fans were and to my mind the cheapo basic models had a nice vintage look to them,,but they do gold and basket weave for those that like a bit of bling! Perhaps a summer line for the likes of B&Q though.
On a slightly different note I tweaked the blades on my workzone fan this morning, gave the blades a twist to increase the overall pitch and this resulted in there now being a waft of air enough to make a single strip of tissue flutter, before there was no decernable air movement, and the effect on the tissue paper from a similer distance was the same as me blowing very lightly on it,,
Steve.


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## Woody2Shoes (13 Feb 2021)

Jelly said:


> How do you find the Rayburn?
> 
> I've been offered one which needs an overhaul FOC if I can move it, and am tempted to take it on as a project as it would fit in with my (eventual) plans to replace the godawful fitted kitchen with a freestanding kitchen setup.
> 
> But whilst I've done a fair bit of research into the plumbing setup needed to use the back boiler (conclusion, I would likely remove and sell it because of the complexity of merging with my existing DHW CH system) I don't really know a great deal about the practicalities of living with one.


You can run a rayburn with the water tank in but disconnected - but I wouldn't recommend using the tank thereafter. We use ours as a space heater and a backup cooker and water heater. We're off mains gas and our leccy used to be unreliable but lots better since it was undergrounded a couple of years ago. It has a huge thermal inertia so you need to plan ahead. It wouldn't really suit people who were out all day every day. It would use about two wheelbarrowfuls of wood per day - fed at regular intervals - or one hod of coal fed twice. It gives a nice dry warmth and we like it but wouldn't want to rely on it as our primary stove/heating! I do like having a choice between wood/coal/oil/electric too - just in case some unexpected crisis forces us to burn the furniture to keep warm!


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## Jelly (13 Feb 2021)

Thanks for the input and info on Rayburns everyone, most helpful!



Woody2Shoes said:


> You can run a rayburn with the water tank in but disconnected - but I wouldn't recommend using the tank thereafter.



I've got a mind to remove it if I do go ahead and get the one offered as I can see how I would use it to deliver underfloor heating using a proportional control valve to split between the floor loops and a heat dump radiator, but would need to work through in some detail to justify the setup to Building Control, so better as an add-on project.

But if I can't (or don't want to) persue that, if the boiler has been preserved I can always sell it on to recoup some of my costs.



Woody2Shoes said:


> It has a huge thermal inertia so you need to plan ahead. It wouldn't really suit people who were out all day every day. It would use about two wheelbarrowfuls of wood per day - fed at regular intervals - or one hod of coal fed twice. It gives a nice dry warmth and we like it but wouldn't want to rely on it as our primary stove/heating!



That sounds like it's actually a good fit, the house itself is stone with substantial thermal inertia of it's own which generally drags things in the opposite direction to the one I would want during winter and the central heating is completely unable to heat the kitchen (mainly down to poor system design) and my office which sits above it.

I work from home, so being in isn't an issue either, although based on the fuel consumption I guess I would need to go down the solid fuel route.

I definitely wouldn't be switching to only a Rayburn for cooking, after growing up in a house where the DHW was from a back boiler I know how grim being forced to burn a fire when it's warm is.





Droogs said:


> it had the back boiler and was hooked up to an underfloor heating system.



I don't suppose you know any more about how that was set up do you?

It seems like it's a bit awkward to run underfloor heating on solid fuel (at least under the current building regs) and there's no obvious commercial solutions out there.





Jacob said:


> They were a great improvement on the open fire range but superseded by gas or electric appliances about 100 years ago



This gave me a good giggle, you're not wrong mind.



Jacob said:


> I've had two. They are a disaster in terms of cooking unless you keep them lit permanently and spend a fortune on fuel.
> ...
> They keep the kitchen nice and warm, whether or not you want it too.



I can see the fuel efficiency/cost issue clear as day... But given I currently spend quite a lot on electricity trying to keep my office above the kitchen even vaugely habitable from November to April, and it's effectively wasted money if I even try to heat the kitchen with the central heating at all, I'm not so terribly concerned as I otherwise might be.

There's a reasonable argument that I'd be better replacing the boiler with a bigger one, and installing additional radiators... But it's only a 3 year old system, and it's a choice between Free (ish) and spending a whole lot of cash, so the numbers stack up in favour of the Rayburn short term.


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## Sandyn (14 Feb 2021)

I had a 4 oven Esse Fairy cooker which was in the kitchen. It was installed in the 50's I kept it alive until about 15 years ago when We refurbished the kitchen. It just got beyond economical repair. Fire bricks broken, grate burnt, just end of life unfortunately. We did get 25 years good use from it. It used about 50Kg of anthracite singles a week I kept my welding rods in the cool oven. It kept the kitchen warm 24/7. Coming home in cold weather, getting up in the middle of the night, or in the morning, the kitchen was always warm. Really miss it.   I still have it out the back of the house. It must be well over 200 Kg. I don't have the heart to dump it.


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## Jelly (14 Feb 2021)

Sandyn said:


> I had a 4 oven Esse Fairy cooker which was in the kitchen. It was installed in the 50's I kept it alive until about 15 years ago when We refurbished the kitchen. It just got beyond economical repair. Fire bricks broken, grate burnt, just end of life unfortunately. We did get 25 years good use from it. It used about 50Kg of anthracite singles a week I kept my welding rods in the cool oven. It kept the kitchen warm 24/7. Coming home in cold weather, getting up in the middle of the night, or in the morning, the kitchen was always warm. Really miss it.   I still have it out the back of the house. It must be well over 200 Kg. I don't have the heart to dump it.
> 
> View attachment 103508


That's a lovely looking stove so it is, I can see how you'd feel an attachment to it.

From your description I have to admit my first reaction was "I've seen locomotive fireboxes get turned round from worse", although I have to grant that the money involved in making that happen is not insubstantial and a fully restored steam loco is rather more of an investment than a solid fuel range.


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## Sandyn (14 Feb 2021)

Jelly said:


> That's a lovely looking stove so it is, I can see how you'd feel an attachment to it.


That's not my one, just a library picture of it. I wish my one looked as good. I have pictures of my one somewhere. It is virtually identical. My stove is out the back of the house covered with a tarpaulin. It really was done!. The hotplate was a massive chunk of cast iron hanging into the fire pit. It had burnt away. I had refurbished it two times before, but the top outer casting was cracked and generally corrosion was a real problem. I think it could still be restored, because it was so well made. I believe all the inner castings are still in one piece, but sitting outside for 5 years won't have helped things. I feel guilty for chucking it out. Things like that need to be kept for the future. It had real character, but a habit of trying to fry my head. It was hopper fed, so at night I lifted the little hopper cover and had a look inside to see if it needed coal. Often I had riddled it a short time before and the fresh anthracite reaching the burning face would give off gas which would build up in the hopper. As soon as you opened the hopper lid, air would get in and the gas would ignite, sending a 2 ft ball of flame out of the hopper, the timing was absolutely perfect. I would normally just be looking inside as the flame ignited. I could see the flame coming, it would engulf my head and singe every bit of hair so I instantly looked as if I was about 90 with white hair. It amused the whole family. The flame never lasted long enough to do real damage. It only happened occasionally, so I never learnt to wait before looking inside. The children and all their friends still talk about it.


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