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

[Phil]

http://www.navitron.org.uk/product.php?proID=67

[Ivan]

I've got one on my stove at home, having been very impressed with the fans which I saw on Dick Strawbridge's Stoves.  My ecofan operates daily for around 6months per year, and has done for two years;

In terms of cost per watt of electricity generated, they don't fair well, but they do a good job of improving air circulation around a stove, which is normally covection alone, and will certainly aid distribution of heat throughout a room. They are a great gadget, more or less silent in operation and the only problem I have had so far is when someone knocked it onto the floor, and caused a ding in one of the blades. Now it is distinctly unbalanced, but performs, nevertheless!


Navitron is an approved stockist of ecofans, by the way.


Ivan

[nelly]

well ive have one that sits on the aga it takes about 7 days to warm the the whole house so when the fan has been on for a few weeks and someone takes it of u notice the temp drop in th living room which is about 2 rooms on about 25feet from kicthen so all i can say buy one u wont know why u did not get it before , i brought mine from fluesystems online they seem to be the cheapest when i was looking

[ecogeorge]

It's difficult to say if they warm the room but I supose anything that helps circulate air is good.
They are compulsive to watch if you can tear your view away from the wood burner flames.
rgds George.

[glennt]

There is also a -spam removed- stove fan. It does the same thing but uses a Stirling engine to power the fan. They do seem to work and increase the room temperature. Athlough it is hard to work how much it saves (lost heat up the flue).

-spam removed- any further repetition will result in an instant ban-

[Baz]

I find the heat initially goes up to the ceiling and works down. Therefore a fan helps to circulate it, that is without directing at the stove to increase its transfer rate.
However 'ecofans' should be banned by any ecologically sensitive measure. Their cost = energy used in manufacture is an order of magnitude greater than a mains fan production and lifetime energy consumption.

[MR GUS]

So, that is your own product you're advertising Glenn?

You'll have found you've overstepped the common courtesy line unless you engage with the moderators first.
This, being navitron will be of interest to folk, however they'd want to know more along the lines of noise, efficiency compared to the existing eco-fan, which dominates the market.

[MR GUS]

I guess though baz it's a case of what's more criminal? an item that spreads the heat over area more effectively or neglecting to salvage heat.

as these have minimal components & units are repairable, they're not so questionable in terms of initial impact, which everything has, probably don't have any plastic (other than wire sheathing) so minimal petro-chemical products, unlike most regular fans ..which are plastic & deemed disposeable especially when the plastic fades, chips or de-stabilizes.

whereas an eco fan (or similar) are built for a lifetime, with a design so simple it needn't really change, therefore tooling costs remain low, &  spares continue...

Not to mention that a great second hand market is visible for this product in part due to the above.

[Baz]

I take your point about plastic but I'm not convinced the thermoelectric element will last long and the things are just so expensive. I think a 'turbine' in the flue coupled to a fan outside would be a winner.

[MR GUS]

Baz i'm curious, did you have one that failed quickly?
Also how long is the lifespan (approx) of a working unit before the module needs replacing (around a tenner to re-fit)?

[County 4x4]

This the first Eco-fan thread I've ever read that hasn't turned into the same sort of debate as "Stihl vs. Husqvarna" on tree forums or "pump out vs. cassette toilet" on canal forums - what a refreshing change!

It usually comes down to one bunch of people saying they're great (the people who have them) and another lot saying "they're Oh, how I wish it was better" (the people who don't have them and will not entertain the idea of trying one!) The first bunch all seem to say they make a big difference though - and some have even posted measurements they've taken with and without to back their feelings up.

I've often thought about selling them myself, as I have an account with the distributor - but haven't done so far. I think the important thing is that they should be correctly placed on the stove - ie at the back towards the side, where cooler air can be drawn up the back of the stove and over the unit. Quite a few stoves have too small a top plate to be able to place the fan in the most effective position, and this may also lead to overheating of the unit.

There are also cheap Chinese copies on the market - more or less exact copies. I know the UK distributors are trying to clamp down on these, although as they're not being sold as "Eco Fans" I don't know if there's anything they can do legally.

Andy

[glennt]

Sorry. I do make them (as it happens by accident). If it is OK with everyone I can answer some of the questions about the eco.

With regard to thermoelectric element lifetime. They should last and they mostly do. The major issue is if they get over 100C~ (they cook and fail), they shouldn't as there is a bi-metal strip under the bottom and the unit tilts back. But they do sometimes do fail. There is a warranty and repair service for such events. The only other point of failure is the motor. It is DC brushed. Again there is the warranty/repair service if needed. Do they degrade slightly over time? (e.g. rpm/volt), maybe but I don't have anything to back it up.

Do stove fans work? (any make)
Consensus is they do. People that I've spoken to that have ran experiments, suggests a few degrees per room. However it does blow warm air at people and to us humans a few degrees makes a big difference! I sure in some cases it works betters than others.

[Ivan]

I have an ecofan. It's sat on my stove for the last 6 years. The stove runs for several hours most days during cold weather. It still works well, and I haven't noticed any deterioration. It doesn't move a huge amount of air, and it's a fairly weak fan, but I'm sure it makes a difference, albeit a small one.

I think that an ecofan would probably have a similar energy footprint to any mains fan, so I can't see that as an argument for banning them.

The main advantage of a heat-powered stove fan of any description over a mains-powered fan, is that you can't safely dangle 240v cables (or 12v for that matter) over the top of the stove (MELTING hazard!). The cost of the ecofan is high, this is due to the fact that the manufacturers, and UK importer puts a hefty profit margin on the device. I'd estimate the actual component cost at under £5, and indeed I've built a few working demo units myself out of standard components. The TEGs are actually pretty cheap too.

A stirling-based stove fan would be just as good, except for two things 1) stirling engines aren't normally self-starting  2)they usually make a fair bit of noise compared to a TEG which makes no noise 3)in my limited experience with stovetop stirling fans ('freebreeze'), they are quite cumbersome, expensive and require far more heat to get going than the ecofan - my woodstove top doesn't reach a high enough temperature to get the Freebreeze stirling engine to run (I have only managed to get it to run on my gas hob).

If anyone wants to donate a stirling-powered stove fan, I'm happy to test it, and if it works well, happy to sell it via Navitron.

[spaces]

I've had no experience of stove top fans  - I use a 'scrap' 12v computer fan behind the stove, wired into the 12v circuit and it improves air temperature very well. I prefer the idea of the nicely-machined mechanical stirling engine rather than a peltier element, a couple of wires and an electric motor. But that's just my taste! Think the cleverest thing about the 'Ecofan' is its name...  

re Ivan's concern over melting wires - what takes electricity to the Ecofan's motor then?

[glennt]

regarding ecofan melting wires. Most wires can take quite a high temp. They are half way up. so that is not an issue. If the wire sheilding is melting then your going to have other issues with the motor and thermoelectric element.

Replying to Ivans comments about Stirling engine fans
1) Stirling engines are not self starting. Well one type actually is but a fan has not been made out of this. So for the time being that is not an option. But people don't seem to mind giving it a flick to get it started.
2) Stirling engines don't have to be noisey. A lot of effort was spent making the ***** fan quiet. There was a few prototypes before the noise levels came down. It is very comparable to ecofan on noise levels. The ecofan has a small fast blade, any noise you get from it is the blade cutting through the air. The ***** has a slower larger blade. You just hear a swooshing from the glass/graphite piston.
3) The 'freebreeze' is different beast. 22inches tall. 16lb in weight. fan blades made from wood. Piston seals made from leather. oil lubrication. it works but....Not everybodys cup of tea for domestic stoves. It is quite noisey too.