Has anyone got an 'Ecofan' and are they any good

[Ivan]

I wasn't suggesting that mains wires melt when suspended in mid air above the stove. I was suggesting that should the wires end up touching the stove surface, they WILL melt, and melted mains wires on a large cast iron stove are not a good combination (and melted 12v cables could case a fire if not adequately protected - before someone says why 12v). With the ecofan, it is very difficult to get the wires to contact the stove surface, even if the unit is knocked over (but that does damage the blade, as my wife demonstrated a few years ago, when hovering the dust off the top of the stove!). In any case, i don't think the voltage of the ecofan shorted against the stove would be a major safety hazard!

[charlieb]

Best thing for me, and it outweighs the heating benefit which I'm not sure about, is that they tell you at a glance if the stove is hot.  My flatmate and I get in at different times, and in the winter tend to light the stove up straight after work.  Squirrel glass is by no means always clean enough to see any flames, so I love the fan because it's like an on/off LED which is a) doing some good, and b) shows 'degree' of on/offness rather than just two phases   (Analogue rather than digital?  I'm tyeing myself in knots...).

Not sure I'd splash out on one just for this, but it was a gift I'm very grateful for.  I've knocked mine off my (small) stove several times without any damage.

[cliffski]

I'm a big champion of ecofans, I have two, a small one and a big one, bought here (was the best price, including delivery).
I think they are incredibly good. Both my wood burners are set back from the room in alcoves, so they are 100% essential for me. I think they are one of the best green investments I've ever made. 100% recommended.

[Lurk]

Being excessively tight at present, but also wanting to hoard kit.....I started looking at what drives the Ecofan    - and found various options for a DIY version. So I am looking to make a small electric fan driven with the same technology as the Ecofan (my budget is £30) and then found this on You Tube - http://www.youtube.com/watch?v=a5LgrEiS7ss (I hope this doesn't break any post rules including a link) - I couldn't resist trying to make one as well with a fan added (budget £40) - just awaiting some bits of copper tube from a plumber mate. I like the idea of recycling bits and bobs instead of buying new - I can use the saved monies to buy another ton and a half of logs. lurk.

[Ivan]

No problem - feel free to post things like that.

Very interesting and clever construction. Be careful cutting the glass though - glass does sometimes shatter, and of course the glass dust is not very good for your lungs - so wear breathing protection and if possible do the cutting out of doors. If you make one, if you have time, please take some pictures and post a write-up. I'm sure there are others who would like to make one, but there's not a great deal of construction info available from the Youtube link

[Baz]

There are lots of stirling engine designs that don't use glass cylinders. Normally they are just a coke can and bean can about 1/4" larger diameter. The thin wall of the can limits heat conduction just as well as glass and anyway there will be lots of hot air rising up. Metal cans can be soldered too for a better seal.
Cost should be in the order of £3 for the essential unsealed ball races.

[Lurk]

Thanks for the Nod ref' posting Youtube Ivan.
Baz - I have seen the stirling engines from coke cans, crisp tubes and all manner of 'trash' as our friends from the other side of the pond call it.... I just really liked the glass body and the fact it worked pretty well & quiet - my little lad will love watching the displacement piston going up and down inside the glass cylinder.....which I am not looking forward to cutting - thought that I would wrap a bit of tape around the cut line to hold bits together  . I should have the bits by the end of next week and I will try to make a record of the construction - I will put it up on my youtube channel and post a link - then at least I stand a sporting chance of being able to upload without having to start frrm scratch to learn on here. Still awaiting the little electric gizmo which converts heat to electricity for my 'ecofan' variant - that should at the least be a quick job to put together and I will post that as well. Then its a case of waiting to light the stove - it been 26 degrees C here in the High Peak - its October - normally I'm looking at the log pile and wondering if it'll make the winter through ?

[Ivan]

I like the idea of glass because it's got a smooth bore = less leakage past the piston

[Lurk]

The displacement cylinder isn't a very efficient cylinder - clearances recorded on a number of DIY Sterling engines are in the region of 1 - 3mm thats upto 6 mm on diameter - Ive measured some sample glass 'cylinders' and the variation is anything up to 2mm on a 80mm diameter - and it varies over the length of the bore - thats based on 'cut down jars & bottles' I got a price of £25 for a 80mm diameter cylinder cut to size from lab' glassware - over budget though and the best they could quote was +/- 0.5mm on diameter.
So my thoughts were work on upto 3mm gap and increase the cylinder diameter as much as possible while keeping stroke short - the extra surface area should allow the air to heat up faster and the added volume should compensate for the leaks. Seams friction is the biggest killer to the operation.

[Baz]

In the seventies one of the common gizmos on the exhibition circuit - you know those stalls that appear at car/home/craft/whatever shows - was a bottle cutter to make glasses (tumblers). It was a regular glass cutter held in a device in a cork in the top of the bottle to hold it at constant height around the target. I think there are lots of ways to run a cutter round neatly and the last thing  would ever consider is attacking it with a dust creating dremel.

The other method for galss jars was cold water in the jar at designated height and plunge it into a bowl of hot water at same height. Heat differential stress cracked the glass. Muast be plenty on the web about it.

[Lurk]

Cheers Baz - I searched Youtube and see a number of 'better ways' than grinding disks  - I should have put my brain into gear before ebay shopping. Just awaiting postie now for some bits of thin brass pipe.

[Ivan]

I cut bottles in half to make garden candle holders - a trick demonstrated to me by a kind gentleman at the Big Green Gathering some years ago. You suspend the bottle from a string attached to a nail in a cork in the mouth of the bottle. The cork has a section cut out to allow air in the bottle to expand, and you spin the bottle on the string. Apply heat using a fine tipped blowlamp (the sort used for cooking is ideal), and after heating for a couple of minutes, whilst the bottle is still spinning you apply a wet cotton bud to the side of the bottle where it was heated. About 80% of the time, you get a perfect crack around the circumference of the bottle

[Lurk]

Seams an age ago since I started looking at this = DIY Eco-Fan type unit. Anyway, finally got mine up and running and it works a treat and for under £30 worth of bits and bobs and postage. you can see an image and some details here - http://www.peakdistrictcreations.co.uk/about-us/environmental-policy/recycled-stove-top-fan/ - I don't know how to upload an image here so I stuck on my own website. any questions drop me a reply.
Lurk

[charlieb]

Congratulations lurk. Looks brilliantly neat and tidy, and I envy that sense of satisfaction you must get every time the stove heats up enough to get it going (I get satisfaction when I see my ecofan going and I didn't even make it!). If I ever get another stove installed I might try my hand at making one too.   Great www too - nice to see a bunch of talented people getting together (even if mostly online?)

[Lurk]

Thanks CharlieB - it is nice when a 'project works out' ! I want to get back to the stirling version - in time....
Thanks to for your positives on the website -its only 7 months old but its building up nicely. Not the best economic climate to get something like that off the ground.
I've just got parts to make up 3 more fans - thats one for my other woodburner which is a Morso Badger - this will have a slightly bigger set up and one which one of this sites members has ordered ( ) and a spare for 'stock' ! I will post some images when they are made up.
Lurk