I recall a comment on stove fans that sit on top of wood/multifuel stoves
but cannot now trace it. Anyone else remember it or who commented please?

I've been looking at some on-line and they appear to fall into two
categories - stirling engine and 'electric' but I can't figure out how
the electric ones work without mains or batteries.

I'd have thought the simplest format would be a simple heat rise
updraught from the stove to turn the fan blades.

What obvious thing am I missing and does anyone have any recommendations
for *currently available* ones at reasonable price. The "Aldiddles" both
seem to have had some but no longer.

Mark Allread wrote:

I recall a comment on stove fans that sit on top of wood/multifuel stoves
I can't figure out how the electric ones work without mains or
batteries.

Peltier effect, can't see many under £50 on eBay ...

On Sun, 06 Nov 2016 16:15:18 -0600, Mark Allread
wrote:

I recall a comment on stove fans that sit on top of wood/multifuel stoves
but cannot now trace it. Anyone else remember it or who commented please?

I've been looking at some on-line and they appear to fall into two
categories - stirling engine and 'electric' but I can't figure out how
the electric ones work without mains or batteries.

I'd have thought the simplest format would be a simple heat rise
updraught from the stove to turn the fan blades.

What obvious thing am I missing and does anyone have any recommendations
for *currently available* ones at reasonable price. The "Aldiddles" both
seem to have had some but no longer.

Over the years I have had a couple , the first was a Caframo imported
direct from Canada when suppliers in the UK were rare.
That was a peltier coupling type where heat differential makes enough
power for the motor to turn the fan. These are often used the other
way round in picnic cooler boxes where applying a current can make one
side cool the box
It worked well and I left on the boat where it was used when I moved
on from it.
A lot of the fans available on Ebay are Chinese rip offs of the
Caframo with varying degrees of quality.
The second one I purchased was actually for my mother who no longer
able to stoke a solid fired Rayburn got an oil fired boiler in for the
main heating but then found she needed a wood burner occasionally.
This was the Vulcan stove which is a Stirling engine type.
It is a far more interesting device to watch if you are the sort of
person who likes mechanical things like an old clock or steam engine.
It worked very well on my mothers large wood burner .
I got it back when she moved and tried it on my own stove , mine is a
lot smaller and the Vulcan doesn't suit it so well on it as the top
takes a long time to get hot enough so I got a valiant ventum III
which shifts a lot more cubic feet of air from a lower temperature.
Both the Vulcan and the ventum are UK manufactured.
I still like using the Vulcan when the stove is hot enough because I
like seeing it working.
This site is one of the best for comparing different models.
http://www.stovefans.co.uk/

The Ventum III is about £40 more on there than I paid a year ago
elsewhere, the Vulcan not a lot more than I paid for the MK1 version 5
years ago.
Whether you consider £60 to £150 pounds reasonable I don't know but
the cheaper ones I can't speak for. the operating environment is
pretty severe so you need good bearings so the fan doesn't vibrate and
drive you barmy and the thing grind to a stop after a couple of months
use.

G.Harman

On Sunday, 6 November 2016 22:18:58 UTC, Andy Burns wrote:
Mark Allread wrote:

I recall a comment on stove fans that sit on top of wood/multifuel stoves
I can't figure out how the electric ones work without mains or
batteries.

Peltier effect, can't see many under £50 on eBay ...

No, Seebeck effect.
https://en.wikipedia.org/wiki/Thermo...Seebeck_effect

On 06/11/2016 22:15, Mark Allread wrote:
I recall a comment on stove fans that sit on top of wood/multifuel stoves
but cannot now trace it. Anyone else remember it or who commented please?

I've been looking at some on-line and they appear to fall into two
categories - stirling engine and 'electric' but I can't figure out how
the electric ones work without mains or batteries.

I'd have thought the simplest format would be a simple heat rise
updraught from the stove to turn the fan blades.

What obvious thing am I missing and does anyone have any recommendations
for *currently available* ones at reasonable price. The "Aldiddles" both
seem to have had some but no longer.

I bought one from Amazon last winter. See their item number B001AYVXRY.
Its a simple peltier effect one which wasn't expensive but works well.

Mike

harry wrote:

Andy Burns wrote:

Peltier effect, can't see many under £50 on eBay ...

No, Seebeck effect.

OK, different sides of the same coin ...

On Mon, 07 Nov 2016 01:33:57 +0000, damduck-egg wrote:

On Sun, 06 Nov 2016 16:15:18 -0600, Mark Allread wrote:


What obvious thing am I missing and does anyone have any recommendations
for *currently available* ones at reasonable price. The "Aldiddles"
both seem to have had some but no longer.

(Vulcan) It is a far more interesting device to watch if you are the
sort of
person who likes mechanical things like an old clock or steam engine. It
worked very well on my mothers large wood burner .
I got it back when she moved and tried it on my own stove , mine is a
lot smaller and the Vulcan doesn't suit it so well on it as the top
takes a long time to get hot enough

Ohh I do like the look of the Vulcan! But I doubt I could persuade
herself that its worth the money!

so I got a valiant ventum III which
shifts a lot more cubic feet of air from a lower temperature. Both the
Vulcan and the ventum are UK manufactured.

This is the one I'm most likely to buy - UK manufacturer with a 2 year
warranty on it as well as a low heat starting point.

Thanks for this!

On Mon, 07 Nov 2016 11:37:35 +0000, Muddymike wrote:

On 06/11/2016 22:15, Mark Allread wrote:
I recall a comment on stove fans that sit on top of wood/multifuel


I bought one from Amazon last winter. See their item number B001AYVXRY.
Its a simple peltier effect one which wasn't expensive but works well.

Thanks Mike - looks an interesting one but I confess to being swayed
towards the Ventum 3 blade which hopefully will be better balanced.

The price is certainly good hmmm....

On Mon, 07 Nov 2016 06:32:06 -0600, Mark Allread
wrote:

On Mon, 07 Nov 2016 11:37:35 +0000, Muddymike wrote:

On 06/11/2016 22:15, Mark Allread wrote:
I recall a comment on stove fans that sit on top of wood/multifuel


I bought one from Amazon last winter. See their item number B001AYVXRY.
Its a simple peltier effect one which wasn't expensive but works well.

Thanks Mike - looks an interesting one but I confess to being swayed
towards the Ventum 3 blade which hopefully will be better balanced.

The price is certainly good hmmm....

I have the £24 one that Aldi sell every so often, works OK. I actually
point it into the alcove the wood stove sits in.

It has the same TEG that others use ( I suspect its the same as in
the 12V beer coolers as it looks the same) and a little bimetal strip
to decouple it from the stove if it gets too hot.

AJH

On 06/11/2016 22:15, Mark Allread wrote:
I recall a comment on stove fans that sit on top of wood/multifuel stoves
but cannot now trace it. Anyone else remember it or who commented please?

I've been looking at some on-line and they appear to fall into two
categories - stirling engine and 'electric' but I can't figure out how
the electric ones work without mains or batteries.

I'd have thought the simplest format would be a simple heat rise
updraught from the stove to turn the fan blades.

What obvious thing am I missing and does anyone have any recommendations
for *currently available* ones at reasonable price. The "Aldiddles" both
seem to have had some but no longer.

try;

http://www.fluesystems.com/

--
Rod

On Mon, 07 Nov 2016 19:43:04 +0000, news wrote:

On Mon, 07 Nov 2016 06:32:06 -0600, Mark Allread wrote:

On Mon, 07 Nov 2016 11:37:35 +0000, Muddymike wrote:

On 06/11/2016 22:15, Mark Allread wrote:
I recall a comment on stove fans that sit on top of wood/multifuel


I bought one from Amazon last winter. See their item number
B001AYVXRY.
Its a simple peltier effect one which wasn't expensive but works well.

Thanks Mike - looks an interesting one but I confess to being swayed
towards the Ventum 3 blade which hopefully will be better balanced.

The price is certainly good hmmm....

I have the £24 one that Aldi sell every so often, works OK. I actually
point it into the alcove the wood stove sits in.

It has the same TEG that others use ( I suspect its the same as in the
12V beer coolers as it looks the same) and a little bimetal strip to
decouple it from the stove if it gets too hot.

AJH

Thanks AJH - I think it was probably your post that I was trying to find
but couldn't. I'll keep trying Aldi and see if/when they get some more
in.

On Tue, 08 Nov 2016 04:08:53 -0600, Mark Allread
wrote:


Thanks AJH - I think it was probably your post that I was trying to find
but couldn't. I'll keep trying Aldi and see if/when they get some more
in.

It's probably worth a punt at £24 but having used it for a few weeks
now I'm not sure of it's benefits. I do see people complaining that
they have a short life, lesson is to keep the receipt as they should
be covered by Aldi's 3 year warranty.

The thing is in a draughty house a wood stove creates a hotter spot
than a radiator so the heat rises quickly. I wanted to force it to
floor level to break the stratification and cut the draughts at floor
level.

AJH

On Tue, 08 Nov 2016 12:32:30 +0000, news wrote:

On Tue, 08 Nov 2016 04:08:53 -0600, Mark Allread wrote:


Thanks AJH - I think it was probably your post that I was trying to find
but couldn't. I'll keep trying Aldi and see if/when they get some more
in.

It's probably worth a punt at £24 but having used it for a few weeks now
I'm not sure of it's benefits.

Ah, OK

I do see people complaining that they
have a short life, lesson is to keep the receipt as they should be
covered by Aldi's 3 year warranty.

The thing is in a draughty house a wood stove creates a hotter spot
than a radiator so the heat rises quickly. I wanted to force it to floor
level to break the stratification and cut the draughts at floor level.

I guess you've visited here then whilst I was out :-) You've described it
perfectly.


Recently been in a caravan that had blown air heating at ankle level -
really nice! All we need now is some way of trapping the warm/hot air
around the stove and then piping it out around the room. A bit like the
US system I suppose where they have a hulking great boiler in the
basement and warm air via ducting. Having said that an American we were
chatting to last winter, coming to the end of his duty tour, said how
much he appreciated the UK system of wet rads and it was something he was
going to look into for his home in the US.

The grass is always greener...

On 08/11/2016 12:32, wrote:
On Tue, 08 Nov 2016 04:08:53 -0600, Mark Allread
wrote:



The thing is in a draughty house a wood stove creates a hotter spot
than a radiator so the heat rises quickly. I wanted to force it to
floor level to break the stratification and cut the draughts at floor
level.

AJH


The cheap one I have helps enough to be worth spending more on a better
quality one if this one packs up.

The holiday cottage we owned in Arkengarthdale up to 12 years ago had an
open plan 1st floor with lounge Kitchen etc. with a wood burner. In the
depths of winter the temperature could be felt dropping with every step
down the stairs to bathroom and bedrooms.

I installed a 42 inch soil pipe (boxed in) with two fans inside to draw
hot air from the apex of the vaulted lounge ceiling down to floor level
in the bathroom. I used two 240 volt shrouded fans with round casings
that fitted perfectly inside 4" pipe couplers, later adding controll by
a simple Bimetal thermostat.

It worked reasonably well giving us a warm bathroom and helping spread
heat around the ground floor.

Three years after we sold the place we had telephone call from the new
owners asking where the fans came from as one had packed up. She wasn't
impressed when I told her they were from an MOD scrap dealer:-)

Mike

On Tue, 08 Nov 2016 07:05:20 -0600, Mark Allread
wrote:

The thing is in a draughty house a wood stove creates a hotter spot
than a radiator so the heat rises quickly. I wanted to force it to floor
level to break the stratification and cut the draughts at floor level.

I guess you've visited here then whilst I was out :-) You've described it
perfectly.


Recently been in a caravan that had blown air heating at ankle level -
really nice! All we need now is some way of trapping the warm/hot air
around the stove and then piping it out around the room.

When we imported some pellet stoves at the turn of the century I was
really surprised that the hot air was blown out at about 1m . I was
keen to design my own that would blow the air from a slot at floor
level, I had seen some experiments that suggested the Coanda effect
kept the warm air hugging the floor surface for a distance and then
rose more evenly.

I have a PC power supply fan and a length of hose from an air
conditioning unit vent that I have also tried but even this didn't
move much heat where I wanted it.

Personally I'm a fan of under floor heating for rooms under constant
occupation, hot air for rooms only used occasionally.

AJH

wrote in message
...
On Tue, 08 Nov 2016 07:05:20 -0600, Mark Allread
wrote:

The thing is in a draughty house a wood stove creates a hotter spot
than a radiator so the heat rises quickly. I wanted to force it to floor
level to break the stratification and cut the draughts at floor level.

I guess you've visited here then whilst I was out :-) You've described it
perfectly.


Recently been in a caravan that had blown air heating at ankle level -
really nice! All we need now is some way of trapping the warm/hot air
around the stove and then piping it out around the room.

When we imported some pellet stoves at the turn of the century I was
really surprised that the hot air was blown out at about 1m . I was
keen to design my own that would blow the air from a slot at floor
level, I had seen some experiments that suggested the Coanda effect
kept the warm air hugging the floor surface for a distance and then
rose more evenly.

I have a PC power supply fan and a length of hose from an air
conditioning unit vent that I have also tried but even this didn't
move much heat where I wanted it.

Personally I'm a fan of under floor heating for rooms under constant
occupation, hot air for rooms only used occasionally.

I'm not. I stayed in a motel once that had underfloor heating and I had
to quite literally lie on the ****ing floor to feel anything like warm
enough.

And in another house I visited for a while, didn't like the hot feet effect
either.