Non-Stove Top Fan

[Thebeeman]

I spotted this item when looking for bits for dead fan (got TOOO hot).
I bought one and it seems to do what the tin said, time will tell.
We have a Rayburn which does not have enough flat area that does not get too hot and also out of finger/arm range.
Also our 2 wood burners have "peaked" tops that are no good for a standard fan.

www.amazon.co.uk/Powered-Chimneys-Firep ... 41&sr=8-11

[Mr Gus]

Hope it works a long time for you.
We bought a cheapy unit & it failed within a few months.

The caframo units are pricier, & I think they sell replacement modules, if it go's down you may wish to have a look at availability.

[Joeboy]

Hope it works a long time for you.
We bought a cheapy unit & it failed within a few months.

The caframo units are pricier, & I think they sell replacement modules, if it go's down you may wish to have a look at availability.

We have a caframo unit for the top of stove and it is excellent. Must say though, quite intrigued by the stovepipe mounted fan idea if it works on twinwall and is silent. Seems like a bit of a nobrainer? Anything really that will increase the 'shove'.

[Thebeeman]

I don't think it would work on an insulated flue, not enough heat getting out. It's silent in operation so far.

[Joeboy]

I don't think it would work on an insulated flue, not enough heat getting out. It's silent in operation so far.

That's a shame, I'll look into my flue surface temp 2 feet up when I get home and also the existing stove fan foot temp. See where we are, thanks for showing this Beeman.

[Joeboy]

Awakening a dead thread. I finally checked my twinwall flue and have surface temps of 75 to 95 degs depending on how low I go. I am quite tempted to try a magnetic mount stove twin fan. They start up at 50 degs...

Anyone got one?

https://www.amazon.co.uk/Magnetic-Burne ... bXRm&psc=1

[AE-NMidlands]

No, but I liked its feature: "it self-regulates based on the stove's heat output" which presumably means it goes faster on a hotter flue pipe!
There are a surprising number of 1-star reviews saying it doesn't work though.

[Thebeeman]

I don't know where the magnetic bit comes from, it looks to be a similar mount to mine, jubilee clip around the pipe. Mine are still going well, I did spray the jubilee clip with black stove paint so that it does not jump out and hit your eyes though.

[Moxi]

JB,

While I love my stove top fan the flue mounted units I fear will be less useful, the temperature difference between the base of the unit on the stove and the "cold side" top fins is what produces the power to run the motor.

On a stove top mounted unit the base would be circa 120+ degrees ? and the air above the stove say 30+ degrees with the air temperature rising slightly as you get further way from the stove top before it starts to cool again as it mixes with cooler air drawn towards the stove by convection currents. In this position you therefore have upwards of 90 degrees Delta T to create the electron flow across the peltier.

On the flue you have 90 degrees on the "hot side" and say 30 + degrees air temp so a delta T of around 60 degrees (probably less in actuality) so yes it will probably spin up but on the slow RPM side and it will be slow to start and quick to stop.

Get an air temp if you can at the point where you would mount it and then temperature for the flue and see what the difference is. I do wonder if the 50 degrees you noted was the temperature difference rather the the sole plate temperature?

Also rather than the fan option have you considered the simple static fin to increase the surface area of the flue and hence convection ? No moving parts = nirvana

Moxi

[Moxi]

another thing to check is the hot and cold side temps of your existing fan at different stages of speed to see what the delta T is and how that relates to fan speed to get an idea about the fan speed for the flue mounted position ?

Moxi