annabellespapa
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Worcestershire and Brittany 22.
Posts: 636
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Post by annabellespapa on Jan 26, 2023 14:25:29 GMT 1
Did you have to push start the Stirling engine each time? To be honest PCPA it was nothing short of useless but I am a gadget man and thus a sucker for anything of that ilk, starting it manually certainly got it going sooner than waiting for it to heat up and get the pistons moving. It was a good introduction to the engine, I gave it to a pal about 12 years ago, he cleans, lubricates it and says it still works fine but it was a lot of effort for me. We have loaned our heat fans to friends who have joined the band wagon and installed wood stoves in the UK with mixed results. One friend has a new build fully insulated house that he designed himself, he uses the fan to push the heat out of the window as the house gets too hot. The solutions I gave him was to put a tea light inside the wood stove to get the glow effect or reduce the size of his logs to 25 cm and put them on one at a time.  |
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Post by pcpa on Jan 26, 2023 14:42:26 GMT 1
I got the Chinese Diesel heater fired up yesterday, if it were not for people posting Youtube videos 99% of them would be returned, the instructions being that incomprehensible and the operating controls so illogical.
It is however a revelation and I am going to use another version of it for the permenant central heating of the sous-sol accomodation so as not to eat into the limited electric current or having to pay for a higher abonnement.
I intend running it on a mixture of Clam-C and 2 stroke oil to protect the pump.
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Post by Polarengineer on Jan 26, 2023 16:41:46 GMT 1
Do they actually generate electricity and use that to power the fans or do the fans rotate through the current of hot air? Looking at the image in the link with the heatsink I can't make my mind up which it is, if they do indeed convert heat into electricity and electricity into rotary motion then how do they do the first part? And I quote,"The Peltier device generates electricity by having one side hot and the other side cooler (known as a 'thermal difference'). This temperature difference creates a 'potential difference' (a voltage) in the circuit. This voltage powers the motor, which in turn drives the fan." I believe it is the Seebeck effect to which you refer. However, whether Seebeck, Peltier, Thomson or Joule, I personally think that these fans are powerless. The temperature differential is so low that the thermocouple effect will not produce a measureable voltage. These fans rotate due to air convection and only disturb the rising air flow. Hang some paper strips in front of the fan and there is hardly any foward flow. Nah a rip off I reckon. |
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Post by pcpa on Jan 26, 2023 16:56:35 GMT 1
Purely decorative then like wind chimes.
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annabellespapa
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Worcestershire and Brittany 22.
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Post by annabellespapa on Jan 26, 2023 18:16:42 GMT 1
And I quote,"The Peltier device generates electricity by having one side hot and the other side cooler (known as a 'thermal difference'). This temperature difference creates a 'potential difference' (a voltage) in the circuit. This voltage powers the motor, which in turn drives the fan." I believe it is the Seebeck effect to which you refer. However, whether Seebeck, Peltier, Thomson or Joule, I personally think that these fans are powerless. The temperature differential is so low that the thermocouple effect will not produce a measureable voltage. These fans rotate due to air convection and only disturb the rising air flow. Hang some paper strips in front of the fan and there is hardly any foward flow. Nah a rip off I reckon. Well this is strange PE, we have used them for years, mainly as our only form of heating in France and I can tell anybody reading this, have you ever sat in front of a nicely running log burner but noticed a chill over you shoulder as cold air is heading towards your log burner, this almost eliminates this and for the small cost of purchase, surely it is worth ago. |
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Post by cernunnos on Jan 26, 2023 18:37:57 GMT 1
When installing a wood stove run a conduit to below it , so that it draws air from outside , no draught. |
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Post by robertarthur on Jan 26, 2023 19:29:41 GMT 1
@ Polarengineer, those peltier elements, I do not have hands on experience and I was wondering also whether it would work, enough power to get a fan moving fast enough? Reading several internet discussions it looks like it is not only PR vapourware. Just to put the necessary power into perspective: a simple 12 V fan from an old desktop computer power supply. Consuming 104.4 mA from a HP laboratory dc supply at almost 13 volts. Modern dc fans will be more efficient. Edit: stove fan repair |
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Post by Polarengineer on Jan 27, 2023 15:21:28 GMT 1
I know that the sellers refer to these as peltier fans, however the peltier effect is when a voltage is APPLIED to the junction to create a temperature difference, whereas the seebeck effect is when a voltage is created by the temperature difference across a thermocouple. I too have no hands on experience of these fans, I'm sure if I bothered to calculate the energy requirement to drive the fan and move the air, it would show that the seebeck effect would not create sufficient energy. I cast these fans in the bin with the Emperor's clothes.
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Le-Dolly
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La Souterraine (23) depuis '05.
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Post by Le-Dolly on Jan 28, 2023 10:22:54 GMT 1
Just an observation: it has been stated, as a definitive, that these fans rotate due to air convection, maybe they do, or maybe they don't. As an experiment, this morning I placed my fan on the induction hob, the fan went into action after only 22 secs where there is no air convection, only heat. Can somebody explain please.
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Post by Polarengineer on Jan 28, 2023 11:07:59 GMT 1
Maybe this experiment has a small fault inasmuch that the induction hob may just be inducing a current in the mechanism. Just a thought. Electrons shooting all over the place.
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annabellespapa
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Worcestershire and Brittany 22.
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Post by annabellespapa on Jan 28, 2023 11:08:31 GMT 1
This hilarious, discussing what a product might do without actually seeing or using it. I am sat in my kitchen, my cast iron multi fuel 18kw stove is just ticking over at 200f or approx 100c both fans are going like the clappers on top (and placed near the rear to pull heat from below and behind the stove, the kitchen is 6m x 3.5m and with an open door to the rest of the house and the temperature in the kitchen at the furthest point from the stove is 21.9c, we could never achieve this situation without the fans.
I don't know about the Peltier fan as it is not mentioned on the packaging but these simple fans work and distribute the heat effectively.
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Post by Polarengineer on Jan 28, 2023 11:12:05 GMT 1
For a QED on your observations AB. What is the heating situation without the fans?
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annabellespapa
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Worcestershire and Brittany 22.
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Post by annabellespapa on Jan 28, 2023 11:19:06 GMT 1
:)PE, it is too cold this morning to try that experiment but I will do it some time and report back. I have exactly the same stove in our open plan lounge, kitchen and diner in Brittany and it ticks over at 200f with very little fuel required (wood and coal), being a stone longere it takes a few days to warm the whole place 5m x 15m but when I was there last week on my own I managed to get the whole space heated to 19c over 2.5 days and kept it there until I left.
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Post by Polarengineer on Jan 28, 2023 13:22:47 GMT 1
I could not live like that, far too hot. It is 14°C in our massive kitchen (7x6x3.6m. ) and a perfect temperature with one wood burner. The rest of the house has open hearth wood fires and being the two of us, we only light up the library hearth in the evenings while we read and listen to music before bedtime.(no telly). The hot air central wood furnace goes on when it gets to -5°C outside and that takes the chill off the house to make it more comfortable. The bedroom windows are closed while the snow and wind is around otherwise they are open all year so that we can hear the wildlife. (Moles making mountains).
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annabellespapa
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Worcestershire and Brittany 22.
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Post by annabellespapa on Jan 28, 2023 14:13:25 GMT 1
Good luck to you PE, I was brought up in freezing conditions at home no heating apart from a Rayburn in the kitchen, I went to boarding school and slept in a dorm where the water used to freeze in your tooth brush mug overnight, not anymore, I can live with cold but choose not to, in the UK we have our central heating on for an hour in the morning, giving me enough time to get the multi fuel stove back up to temperature and then it stays on all day heating the whole house. In France when we purchased our stone longere in 2009, we inherited a full 2000ltr tank of gas (LPG),we lived there for three years from 2010 and still have 40% of the gas still in the tank, so it is there if we need it. I like to give us options regarding heating because I can't stand being cold. Today it says it is 6degrees outside but it is a UK damp cold that I hate.
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