Introducing the Recoheat heat recovery unit for wood and solid fuel burning stoves
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- Опубліковано 17 жов 2024
- Slash your heating bills with your wood burning stove and the Recoheat heat recovery unit for wood burning stoves and solid fuel stoves. If you're using a stove to heat your home, log cabin, tiny (or big) house, boat, camper or den, you'll want to check out the Recoheat stove accessory. It pumps air through a sealed unit in your flue and pumps the air out at over 500 degrees Centigrade at peak temperature. By that time it's expanded to 3 times its volume, so is coming out at 3 litres per second. And the best thing? The pump uses 37 watts of power, so costs much the same as a light bulb to run, and it will continue to pump warm air recovered from the stove for hours after you stop putting fuel on.
Three years after we launched this revolutionary product, we're going from strength to strength, with customers across the UK and in the US, Canada, France, the Netherlands, Bulgaria and even Australia!
View the comparative heat dispersal of a stove with and without a Recoheat here: • Comparative video show...
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There's an update and FAQ video here: • Recoheat Frequently As...
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Check us out at www.recoheat.co.uk
Keep in mind that I've only used it for a couple weeks, that being said, so far so good ua-cam.com/users/postUgkxAU9pOCSV9Y5JprooHvfxTpOrt4hx8uRM . Using it at 8 ft. by 8ft. deer blind that is insulated. I have to keep the door cracked for it to get enough air to burn, but that is very likely the wood I've used. Much better quality than I expected for the price. Now if I can just take it easy in the beginning it won't be 90 degrees in my blind. All in all it seems like a keeper.
Very impressive tbh , i love my woodstoves and the time they take to start emitting useful heat is indeed their only drawback . Well done Sir .
Thanks very much Jack!
Are you saying that the air that comes out of the front nozzle is 400 degrees? isn't that dangerous?
Over the top of the stove, it's hot, yes, but so is the stove. The only time you have to be careful is for the twenty - thirty minutes whilst the stove is getting up to temperature, including while it's cold. The air from the unit is that hot within a minute because it's from the combustion, so the stove temperature won't warm you of that.
Hmm, I love it. I'm concerned that lowering the temperature of the flue would allow more creosote and condensation to build up.
The use of turbulent air to extract heat from the flow of gases means that the proportion of heat extraction is very low, and the cooling effect proportionally negligible. This was tested by BSRIA and their external independent data is available in their report and certificate on our website: shorturl.at/gtuS0
Burn properly dry hard wood
I don't use a double skinned insulated flue directly on the stove. A single skinned one radiates quickly into the room. If wanted heat distribution I'd use a nice quiet stove top fan. What you have, is fantastically noisey.
For sure: a single skin will radiate about 1kw per metre, apparently, but that does cool the flue far more than our device, and in any case will not circulate any better. In terms of heat distribution, the Recoheat isn't relying on radiant heat to function, so continues to distribute even when the stove is cooling. It's a very different thing, and functions in a completely different way. The noise of the turbulent air coming through the outlet is indeed distinct but it's by no means 'fantastically noisy': air and water flow mess up microphones so it sounds louder on video. In a silent evening of contemplation, you can just turn it off, but in a room with anything going on, you don't notice it.
@@OKuusava I put the 'stones' out of old electric storage heaters around my stove
I agree just far too noisy
Nice! This got me to thinking and wondering if a passive system like this would also work. Essentially just as pictured only the outer pipe terminates about a foot or two from the ceiling, possible even a bit cone-shaped, wider at the bottom, to create a Venturi effect. It would naturally draw cooler air from the bottom and exit warmer air from the top. A Peltier wood stove fan could possible assist with this. A system totally removed from the need for electricity should there be a significant interruption or for off-grid settings. I'm not an engineer, just ruminating is all. Anyway, great idea. mate!
Thanks David - really appreciate it! It's something we're exploring, but as described it doesn't work because the air has to be forced to make it turbulent. It's the turbulence that creates the super-rapid heat transfer, and therefore the expansion and acceleration which in turn creates the vortex effect that draws the heat away from the stove, and the pressurisation that precipitates the heat dispersal via the equalisation. That in turn is why the heat transfers so far - because it's not being pushed, but is exchanging as part of the equalisation and subsequent convection flow. It's really interesting!
Already exists
I worked for a stove manufacturer...the wood stoves they provided met California EPA emissions. 2.5 - 4 grams of emissions per kilo of wood fuel.... very efficient
Modern stoves are fantastically efficient. Our unit addresses the poor heat displacement that is implicit in requiring the combustion to draw cool air towards the bottom of the stove, into the combustion and up to the ceiling, and up into the flue. We're providing a supplementary powered method of heat distribution from the same heat source which is extremely efficient and effective.
Is there any harmful gases being sent into the room? Off grid no electricity think I’ll stick with the fan attached to chimney best buy I’ve ever made
No mingling of the pumped air and the combustion gases at any point. If your fan is working fabulously and does what you need, don't fix it! This product is aimed for people whose heat doesn't circulate effectively around their homes, and achieves that far more effectively than anything else, by a long way. But of course, if you don't need it, happy days!
blowing air into the room? I didnt see the vent! |EDIT| 5:43 I see, so your product is just the vavle between a stove and a chimney? The coil heats up air and you pump that air into the room? This is quite cool. I'd have to see what stove to get
That's right! Thanks for checking it out.
Hi there this looks a good solution but why is it so high priced the material cost can't be more then £35 and my stove was only £366 and the price of your recovery unit is £299 its going to take many years to recover the £299 please explain your price before i invest many thanks Budo
Hi Budo, alas the material costs, fabrication and technical costs are considerably more than that. I'd buy them from you if you could produce the units and the pump, and the silencer for that, but you'd have to be CE marked first, as we are. It's not a cheap industry to operate in, as you'd imagine for safety reasons. The heat output and fuel savings mean some people replace their oil, gas or electric heating entirely with their stove, so recoup the cost in a month. The system really does make that big a difference. You can see our customer feedback on TrustPilot. Thanks for your interest.
@@Recoheat Thank you for your reply sir could you please answer one more question before we make our minds up on buying two of these for our French farmhouse how long is the stainless steel coil component inside guaranteed for and its general life span many thanks Budo
@@FrenchFarmhouseDiaries Hi Budo, the unit is guaranteed for five years, and the pump for two years. The pump will wear out eventually, but the coil won't: it's made of the same material as the flue itself, but is thicker. and the form is much stronger. External test engineers stress tested it to over 900C, and you can't see any difference, as you cannot after years of use. I hope that gives you the confidence you need!
What if the power goes out. Is there a bypass or will you burn the unit out. Thanks
No, it makes no difference. The coil is made of the same material as the flue so is not affected by the heat. You can switch it off if you want to. It is thermal shock tested to 800°C which. Is hotter than the flue gas temperature.
@@willburrows great stuff! Thanks for your time and knowledge 🏆🔥👍
Hi, nice video but I don`t understand it :-) Please explain again because as I understand, you are pumping the hot air from the stove into the house ?. The exhaused air ?! I can not imagine that. What do I understand wrong ..? Please explain again or can someone else please ? Thanks !
Hi Christian, thanks for the interest. No - we're pumping clean air into a sealed coil that passes through the flue. So the clean air is heated, then comes out of the front of the flue in a little nozzle. That blows over the top of the stove and carries the heat away and around the house. Do take a look at our other videos - they make it a bit clearer!
@@Recoheat thanks you very much for your quick response. Clear now :-)
Now I am wanting to buy a northern cabin up in the mountains so I could get me one of those things! Great looking stove. It would be great if you could share some of that heat through a spiral duct into the other parts of the building.
People are coupling this with ducting and circulation systems. Generally it does shift the heat a long way in any case. Customer has got one in a cabin in the mountains near Sacramento: I thought it was hot there, but he gets 6 foot of snow in the winter. Fitting the unit means he doesn't have to get up in the night to put more fuel on the stove.
Can you give a brief explanation how this works? So looks like you have an external air compressor pumping air into where? The firebox or the double walled chimney? Where is the air coming out, the firebox or at the bottom of that double walled chimney?
If you are pumping air directly into the firebox, how do you damper down your air supply to slow down your wood burn rate?
The air is pumped through a heat exchange coil set into the flue, but completely sealed from it. The air therefore does not enter or effect the fire box or directly effect the flue gases. The coil has an external surface area equivalent to 10cm of extra flue length on a 125mm (5") flue, and 6cm on a 150mm (6") flue, so it presumably cools the flue an equivalent amount, but it doesn't make a measurable difference to gas temperature or speed, because an unbalanced chimney is such a lossy system. The unit works by heating and accelerating the air to form a jet of hot turbulent air that draws the heat of the stove away and distributes it very efficiently as the air pressure equalises in the room. The fast heat transfer and constant flow - powered by the pump rather than heat-driven convection - means that the effect is instant, and is maintained for a considerable time after the stove itself cools but the embers are still hot, so that useful heat is circulated for much longer.
Sounds like it must draw the air inside the cabin through a double. Skin flue heat exchanger. No danger of fumes getting included. If it’s a good thick metal on the flue hot side. Control could only be vented to outside if excess heat inside cabin.
Recoheat's reply doesn't fully answer this person's question 😡 WHERE does the pumped air EXIT the unit to heat the room? Can I hazard a guess that it,s just that littl pe hole where you stuck the thermometer in?
Please advise if my assumptions are correct: Electric heaters put out the following: 294 CFM (500 m3/h) (8325 liters per minute) 4800W /16382 BTU Recoheat heat exchanger runs at (9CFM) 240 liters per minute and perhaps 500 BTU. As a percentage of what a wood stove puts out it is a minimal amount. Recoheat 500 BTU divide by Wood stove 30,000 BTU is about 1.6% recovered BTU. However the pump uses 40 watts and savings on wood would be spent on electricity. At best a break even situation.
Hi Robert, thanks for the engagement. It's a great comparison, but yes, is missing the point. The Recoheat doesn't use power to generate any heat - it's powering the pump. That too would have little effect except that the coil is creating a turbulent barrier layer in the airflow with it. This creates almost instant heat transfer so that the air flow and air pressure significantly increase. So the 37w goes into producing a mini jet of turbulent hot air that crosses the radiant heat flow of the stove, energising it and drawing it away from the stove so that it disperses heat from the stove continuously and by temperature and pressure equalisation with a turbulent field, which is again incredibly efficient. We observed it for a long time before we understood it - the difference it makes to heat distribution is bizarre - and producing a simple algorithm for it is very difficult because of the many factors impacting the actual heat generation and the air flows in and around the heated area, but empirically, it makes incredibly efficient use of your resources by dispersing heat so efficiently through a complete cycle of combustion.
@@Recoheat Do you have any test data showing how much extra heat is produced from a burn of a few logs (2kg)? I understand that your device is a heat exchanger. How much extra heat does it produce? Do you have data on this? The shed you are doing the testing in appears to be 10 feet by 10 feet by 7 feet or 70,000 cubic feet. By using the fixed area of heating and a fixed amount of fuel can you do a comparison of the room temperature after one hour, with the Recoheat and without. I am still a skeptic and would like to see real life data as opposed to some pseudoscience science explanation. I live in Canada and heat several buildings with wood, and use 3 bush cords (128 cubic feet in a cord) of wood. I would like to reduce the amount of wood I burn. Each test should collect data in regular intervals of out door temperature and temperature at several locations in the shed. Test should start from a cold stove and each test should use the same amount and type of burning fuel and all windows and doors closed. The following can be used to record the results: uk.govee.com/collections/thermo-hydrometer As we say in Canada, "proof is in the pudding" or "money talks, bullshit walks".
@@rob3bbb Yes, we ran a similar test, but measuring output from points around the stove, and from the Recoheat outlet. It's here: www.recoheat.co.uk/_files/ugd/fe64a7_baca54d990bc43b79befc362dd8d8c38.pdf The volume of that workshop is actually 20' x 14' with quite a high ceiling, so measuring temperature change would have to be relative, which is always difficult in the UK because the weather is so changeable. It's certainly something else to do though. The results would be just as refutable though: we don't have a lab.
@@Recoheat My wood stove Flue runs at 200 C because it is 80% efficient and recirculates gases before exhausting to the flu. Q = 40 x .04769 x 200 = 381W Wood stove is 13000W. 381W/ 13000w = 2.9% too low to justify using this device.
Why isn’t there a view of the “gubbins” that makes up this Recoheat device?
I haven’t a clue what it looks like, where it fits or how it works.
Gosh so many questions this raises. The important temp is that at the top of the chimney if that drops too low creosote will condense out and chimney fires become a real probability as it starts running back down the flue. 300-500 c is a good range to ensure efficient combustion which minimises this risk. Don’t try and keep your fire in all night my ramming it full and closing it down, best way to create a creosote problem. I’ve seen people take a 6 inch flue down to a 3inch one in 3 months doing this even when burning dry softwood. Dry timber below 20% moisture is essential, too much soft wood equals higher creosote risk. Sustainable source of timber essential. To prevent cold air being drawn into the house/room to feed the combustion I’d recommend external air piped underfloor to the stove. Then you can draft exclude your house and prevent cold air being drawn in. Many stoves have a underfed system allowing this. Regular flue sweeps should indicate combustion quality if you’re getting big chunks of black clinker alarm bells should be ringing. My stove flue is swept twice a year and I get about 1/2 litre in volume of fine Sandy texture soot. Tiny granules. There is a science you need to learn balancing hard wood / soft wood ratios and stove temps with dry timber and good companion burning. I love it and my wood shed is my favourite place lol.
Thanks very much for your thoughts! Do take a look at our other videos to see how the unit is working in the wild, so to speak. The point about ramming your stove to keep it going all night is very pertinent: our unit delivers a similar effect without any additional fuelling because the pump keeps the heat from the cooling stove circulating for so long. 👍
is this approved to be used in the US? i have read alot of comments here i think you should start by showing us this unit out of the stove then show us how it works. not everyone will go to your site
Sure - this was actually the first video we made, and we've since worked hard to tell the story better. It's approved for the UK and the EU - we've not submitted for the US yet. Lots more videos on our channel! Thanks for your interest.
That's very good.
Questions:
Can you stack a couple of these Recoheat units on top of each other?
Can you link the nozzles to pipes that go into other rooms?
Can the pump start up and shut off automatically via thermostat, say at 50 degrees?
Thanks Bluce - velly kind. Stacking: yes, if your flue is hot - check out Philip who has three on top of each other! ua-cam.com/video/SwUB78xd_hk/v-deo.html Also done a video on extending the outlets: ua-cam.com/video/MC9W0gbS5kA/v-deo.html You'll see from that, that it is now possible in a limited way - before this breakthrough it wasn't because the turbulent air cools so fast inside a cold extension. Even with the coating we can now do, the end result will only deliver the recovered heat, which is a fraction of the total heat output of the unit when it is gathering and circulating the radiant heat from the stove, so it's very rarely going to be effective. At best, it will deliver about 20% of the total output you'll get from the unit blowing over the stove. Lastly, we don't have automatic switches though people have the pumps plugged into smart switches on their sockets, usually with a timer, but you could set a thermostat on some of them. It isn't necessary because the units get hot immediately, and even overnight will be pumping warmer air, even if it's only 30 degrees C. Thanks very much for your interest!
@@Recoheat MI I'm
@@stevepeck7931 Thanks Steve!
What volume of air does it blow in?
Sorry for sounding so ignorant but what is going on here? Which pump? Where is the air coming in ? Where does it come out? Is it poisonous fumes coming out into house? Not sure what is actually happening here. I have two heat operated fans on top of my 7.5 kw multi fueler.cheers.
Yeh, sorry it's not as clear as it should be. There's an update and FAQ video here: ua-cam.com/video/fOdsE-DVGTo/v-deo.html and the website has lots more straightforward info at www.recoheat.co.uk. We've just put a video of a chap visiting us to hear the device working which shows more as well: ua-cam.com/video/u-40U5Y6byc/v-deo.html
@@Recoheat cheers 👍 🔥
Generally, you want flue temps to remain high to prevent condensation. Removing too much heat is a recipe for a chimney fire.
That's right: hence our use of the turbulent boundary layer phenomenon.
You nailed it...... I tried something similar several years ago and as you indicated it caused the build up of creosote, resulting in chimney fire..... it wasn't a major disaster, but could have been.
BSRIA tested the system for safety, and a key element of that was the temperature monitoring all the way up a 4.5m flue. Their report is here: shorturl.at/gtuS0 You can see that it doesn't cool the flu as you suggest.
Interesting to compare to a Rocket stove where the "flue" is kept as hot as possible for a metre or so to achieve a complete burn for both fuel efficiency and to minimise tar build up and other pollutants in the exhaust. Ideally you would want an initial very hot section of flue (as above) before starting the "heat recovery" which is the stated purpose of this design.
@@rhiantaylor3446 That's an interesting perspective. The hot burn is certainly crucial, but a big difference with our heat transfer is that it is exponentially increased in rapidity by the use of the turbulent barrier layer, so the resultant heat transfer away from the flue gases during their flow past the 9 inches or so of the coil, is absolutely minimal - so much so that it is undetectable. This is completely different to the loss in a section of single skin flue, for example. The volume of flowing flue gases passing across the coil is proportionally very small to the total, and the over-all drop in temperature is undetectable by our own measurements and in the external laboratory testing. Turbulent air heats in a completely different curve compared to a laminar flow.
if you remove that heat that would otherwise rise thru your chimney and keep the creosote from building up, would you need to clean your chimney much more often?
Thanks for your interest. The vortices created by the coil in the flue gas flow, and the relatively small amount of heat we take out - equivalent to that lost through 10cm of extra single skin flue on a 125mm flue, and 6cm on a 150mm - mean we don't have any discernible affect on the functioning of the flue. In a normal system, there is less build up of soot on the coil than on the flue sides.
I live in an old house with insulated floor board. The stove still draws in cold drafts from the heated air rising in the chimney. Drawing air from out side, heated using the flue gases and pressurising the room seems to make sense. The last couple of stove fans didn’t last long and they are noisy so this might be worth a go. Even at £299.
I salute your perspicacity! Thank you for the interest.
@@Recoheat well really I was responding to caper who's house got cold for the intake draft.
@@carpediemarts705 Me too! I just clicked on the wrong 'reply' or it mis-directed me. I blame the technology.
That’s fine, except you’re drawing in outside air and not heating it up that much (or else the flue would cool too much, which would affect stove efficiency and would increase creosote formation in the flue). So unless you live in a marginal climate where you barely need to heat at all, that makes no actual sense, unless the air coming through cracks in the floor is untempered outside air, in which case you have bigger problems than a stove accessory can possibly address. If you live in a sufficiently well airsealed and insulated building, you aren’t getting drafts in the first place and don’t need to pressurize in an attempt to reduce drafts. Also note that it is unlikely the compressor, fan, or otherwise used in this product can move the needle on building air pressure and prevent perceptible drafts.
@@2brazy4ubitch Yes, that's pretty much everyone's assumption, especially the engineers. The secret ingredient you've not taken into account is the effect of the turbulent boundary layer phenomenon. That transforms the heat transfer process, and is the sole reason this device performs in the way it does. It causes the heat transfer efficiency, and also the vortex effect of the flume coming out of the unit across the top of the stove. These combine to drive the heat transfer through pressure equalisation, rather than a forced-air effect. The funny thing is, that you're trying to prove it's not possible, whereas we've been trying to fathom why and how it works, and it's only been by engaging with engineers that we've actually reached an understanding of that. But the really easy bit has been to experience it. It was developed through very thorough experimentation and intelligent iteration from the initial concept, and it improved counter-intuitively, but that's because of the characteristic of the boundary layer physics, and the flux and fluid dynamics of the coil, which we could observe but not understand. It's very interesting. Luckily I'm Cambridge-based and have some clever people to turn to. One of the first was a post-doctoral research scientist with four degrees and two PHDs, and we've kind of maintained that level of collaborative exploration. And the fantastic thing is that everyone involved is learning about something that Kevin, a plumber in Burnley, invented, and whose careful and highly scientific iterative process resulted in something so effective.
I have a small semi detached 1936 build limited insulation due to narrow cavity. I have a 5kw duel fuel stove wood / coal when it's lit we have a standard fan sat on the top which forces heat away from the fire into the room. We then open the doors and it heats the rest of the house not substantially but enough to take the chill off. How would a £300 plus fitting benefit my household? I like the idea but expense outweighs return removing justification for the outlay.
Thanks very much for the interest. If the rest of the house is affected when you open the stove doors, it will be warmed by the Recoheat because the air flow is obviously good. Currently you're only getting that effect when you release the heat contained in the stove, providing a boost but completely cooling the stove. The Recoheat will provide much more than that boost continually (because the heated air is pumped, and your stove is still relying on convection when you open the door), from as soon as you light the stove, until the embers are completely cool. It will make your stove far more effective, and maintain the temperature such that your brickwork doesn't fall below the 15C at which it ceases to provide thermal insulation, so the effect is massive. To get an idea of the difference it makes, listen to what Sam Hamer says about his installation in their showroom: he's using one stove with a Recoheat instead of two stoves, so he is doubling the effective output - and halving his fuel cost: ua-cam.com/video/LbMzmdYHVgI/v-deo.html
Could this be powered by a thermoelectric generator on/in the stove? Would make more sense for off grid applications.
Theoretically it could, but they don't produce a lot of power, and we do, as Mike pointed out last year, have to overcome a pressure drop that makes a power demand that's not insignificant.
As is, everything is relative E=mc 2 , I wonder if you were to double up on the diameter of the coil still leaving room for flue sweep you would double your output, in theory this should work. 1 KWatt would be a nice target to reach on a 4 KWatt stove, on estimation Im getting around 200 to 250 watt heat output on full burn using oak and ash only.
It would cause a blockage in the flue, and cause cooling of the gases. We have balanced the physics very carefully to prevent that.
Hi from nz, sounds great but terrible description.
Where is the air pumped to ,which bit is the recovery unit?? I don't get it 😕
Sorry! The air is pumped to an inlet at the back of the flue, just above the collar. It goes round a steel coil inside the flue, which is the recovery unit, and out at the front, above the stove. There's a better presentation at ua-cam.com/video/tknNKch8ED8/v-deo.html and an FAQ video at ua-cam.com/video/fOdsE-DVGTo/v-deo.html The website also has images and a lot of detailed info - www.recoheat.co.uk Thanks very much for your interest, and al the best to you in NZ! We're very keen to sell in your market, and will ship direct with a contribution to costs of just £25.
@@Recoheat ill check it out thanks, ive just installed a new fire an this is very interesting.
cheers over
I am all about efficiency as far as not wasting heat but I am wondering about slit and Crystal build up increasing because of a cooler exhaust going out of the inside of the pipe since you were pulling heat off of the pipe slowing the exhaust flow.. I am wondering when this will start having an effect as far as how tall your chimney is?. The main cause of Jimmy fires is build up inside of the chimney from not having a hot enough stream of exhaust leaving the house. A shorter chimney wouldn't be that big a deal probably but only two story home I don't think I would be comfortable with cooling my exhaust that much. 🤔
Thanks for your interest. That's obviously the crucial concern with putting anything inside the flue, and is the reason our device works when units with a larger surface area or using water, for example, would do what you suggest. Our unit by contrast does not cool the flue to any significant degree because the turbulence the coil creates in the gas flow, actually reduces pressure on it so it can flow better. At the same time, the total surface area on the coil is equivalent to 10cm extra flue length on a 5" flue, and 6cm extra on a 6". That means no properly functioning stove can be affected by it, because they have to cope with minimum variation in flue height of at least 5m or so. The system was tested by industrial engineers BSRIA as part of the CE-marking process, and they found no adverse effect on temperature or draft. Their certificate is on the website: do take a look, and thanks again for the interest.
I took the temperature of my flu and log burner and it had the same temperatures without the recovery system? I just control the airflow through the vents of the log burner to increase or decrease the flame adjusting the log burners temperature … I’m not really sure how more efficient this flu recovery would be as opposed to adding some burner top fans and increasing the temperature in the burner by closing down the vents to slow the burn ?
Thanks for the interest. Our unit doesn't affect the combustion or temperature. We're capturing the existing heat, but the difference we make is caused by the way we circulate it. We use the electric pump to force air into the coil where it becomes turbulent. The air is heated very quickly therefore, and expands and pressurises, and the jet of turbulent, pressurised air then passes out across the stove, from which radiant heat is rising. The two heat sources, the one small from the flue, and the much larger from the stove, combine and are driven by the pump. The key to the distribution then is actually the pressure equalisation, which carries the heat to the lowest pressure areas, including the floor. It's a combination that works far more effectively than heat-driven convection, particularly as it doesn't depend on you constantly refuelling your stove.
@@Recoheat interesting I’ve been looking at sand batteries and I was thinking about making something similar but using sand as the material to retain the heat and then blowing air through it similar to yours
So you have some type of a coil or heat exchanger inside the flue pipe with a fish tank aerator sort of thing pushing air through it? Why not put an 8 inch pipe over the 6 inch flue pipe seal the top and the bottom put a blower in the top any size blower you can configure and put a couple of vents on the bottom much more heat will be captured and you’ll be able to deliver I haven’t done the math but 20 3050 times the amount of hot air that you have coming out that one little three eights port?😳
Thanks for the engagement. Two reasons: the first that you'd be cooling the surface and bulk temperature of the flue far more than highly efficient stoves can support, and cause creosote to build up in that area. Second, your air flow would be much higher volume, but laminent. We're using the jet of turbulent hot air to entrain the radiant heat from the stove body and draw that out into the room. If you look at the physics modelling of the device in this video, you'll see that the subsequent airflow oscillates and disperses the heat to fill the area floor to ceiling, so is far more effective: ua-cam.com/users/shortsI6TFB8cac04 Thanks again for your interest.
Always a good idea to turbocharge a heating appliance - it'll boost efficiency loads.
One issue - chimney sweeping.
There's a 65mm space through the coil, which is easily managed with a 25mm rotating head. We have sweeps using and installing it - as well as cleaning it for customers.
@@Recoheat Good to know, thanks!
@@Recoheat Is there still the same amount of smoke coming out of the chimney or is it a more transparent smoke?
@@lenny108 It doesn't make any difference to the smoke, because it has no access to, or effect on the combustion, and the spiral coil doesn't slow the draught.
This isn’t “turbocharging”, there is an outside energy input via electricity.
Cool demo. Still dont know what hardware items constitute the Rico system - fan, stove jacket, piping, controls, thermostat?
You can check it all out on the website: www.recoheat.co.uk. Basically it is an air pump, feeding a heat exchange coil set in a flue section that fits into the top of the stove/bottom of the flue, with the outlet just above the top of the stove. So it blows a jet of hot, expanded air across the hottest part of the stove into the room and keeps pumping until you switch it off.
The heat is being recovered, but where is the smoke and flue gasses going?
Hi George - the system is sealed, so doesn't affect the smoke and flue gases - they just carry on going up the flue.
All well and good, but I was told that a hot flue was required to burn off hydrocarbons which otherwise can coat the inside of the flue or chimney.
That's fine - hence our design, which minimises the heat removed by taking it from the centre of the flue rather than the edges, and does so via a surface area equivalent to 10cm on a 5" flue, and 6cm on a 6" flue - so comparatively small that it cannot make a difference to a functioning stove/flue that has to be able to deal with a variation of metres of flue height. The issue is key to our design.
Are you recovering heat which would otherwise be lost to the outside of the building ?
That's right. But we're then pressurising it and by jetting it across the top of the stove, using pressure equalisation to disperse the heat from the stove much more effectively. So the effect on the heat in the building is far greater than what we gain from the heat recovery.
Hi, congrats great product I'm getting one, regardless of noise. Yet would you please measure the decibels of noise of the pump and hissing combined? a decibel meter app in your phone will do. Thank you amazing product.
Yes, sure: we measured with a sound meter, but because it is trying to measure a flow, microphones hate it! We'll try with an app.
Hey 1 2 - we've done that, and here's the video: ua-cam.com/video/z0t3_nrurZg/v-deo.html - it comes out at about 9 decibels. There are notes in the description of the video so you can get the same Decibel app to do a comparison. Thanks very much for the interest and the suggestion - great idea because it's actually creating data you can compare. 👍👍
@@Recoheat Thank you! 9 decibels is nada. I'm ordering it soon!
Love your little stove with the glass window. I'd actually like four windows on mine, and I'd set it more into the middle of the room. Cave Man TV at its finest. I'd been thinking about this idea for years and even went as far as to write a letter to Corning to see if they would make a stove that was entirely glass. They must have thought I was Bonkers.
Hey Jack, and they weren't wrong - join the club. We'll be issuing certificates soon.
Am I missing something here. You power the air pump to blow a small amount of air around a slave fitted to the chimney. The air is them blown out at a high temp through a small hole. That can't be right surely.. bog standard fan will move the air much better I think I think 20 to 30 would be better than 500 degrees.
Their claim is that using a heat exchanger in the flue extracts heat from the flue gases that would other wise be lost. Standard practice in large systems (steam locomotives used 'superheaters', a similar idea). However, in a domestic stove, the available heat is very small. They have done flawed calculations to give unreasonable claims (into perpetual motion machine territory). In addition, the design is far from optimum to reclaim the small amount of heat that is available. They get very hot air- but very little of it.
@@Tensquaremetreworkshop yer I understand the principle of it but as the stove puts out a lot of heat into the room it's in. I don't see the need to add more heat. Well what extra you will gain from an aquarium pump. Plus the flue is the first to heat up but the first to cool as well. The cast stays hot a lot longer that the flue does. Going off my stove anyway. If your place was open plan and a big area it might work. Not, surely a desk fan that uses 10 or 15 watts and moves air would be a much cheaper and a better alternative and it won't cool the flue
@@paulos9304 They make two claims-
- it heats more rooms. They give no logic to this, and no explanation.
-it doubles efficiency. As you cannot double the normal 80% of a log burner, this can also be dismissed.
Moving the heat to other parts of the room can, as you say, be achieved by assisting airflow with a fan. As many people do.
Their system will recover some heat, but very few people would want the complexity and cost in exchange for using, say, 3% less wood...
@@Tensquaremetreworkshop well I did get a laugh at it. It's comicle. Its 300 or whatever it costs down the drain. I can't see the point in this this at all
@@paulos9304 Wouldn't removing a meter of that twin wall and replacing it with vitreous do the same thing for a fraction of the cost?
Ok, i have an older wood burner that this would fit.
What is the power supply and current draw? Basically how much does it cost to run per season but more importanly, does the additional draw cause a much faster burn of the fuel?
It's 240v or 110v and is rated at 37w but draws 17w in operation. It doesn't affect the draw or combustion at all, so there's no effect on the gases except that you're circulating clean air instead of a convection flow from the floor. Because you're heating the air flow rather than the body of the stove, you use significantly less fuel than a conventional burn.
@@Recoheat Thank you for getting back to me and explaining.
Will be in touch. Thanks a lot.
does the pump need to be outside the house or just outside the stove?
It doesn't need to be outside the house, though it can be. It just needs to be somewhere you can't hear it. It's a big aquarium pump so it needs to be on a solid surface and baffled from the room, usually. The acoustics in the room actually make a big difference and causes a wide variety of impact, but outside the room is best for most people.
May I ask what is the nominal power of the motor in the air blower of this system?
The rated power is 37w, but it actually draws 17w when running the system.
theres been flue heat revery of stoves for 100 years?
Yes, lots. Not like ours though, and they all use a laminent flow of air, which has quite different properties.
maybe I miss something I don't see any explanation what the heck it is you're trying to sell I don't see any link for what it is you're trying to sell I don't see any information of what you're trying to sell is how it works what it does
Website with more details is at www.recoheat.co.uk
I would have thought having a large radiator for the stove exaust to flow through would have been a good idea, I imaging a huge amount of heat is wasted just going straight up the chimney.
The flue needs plenty of heat to function - a radiator is a big cooling system, so would just stop the flue gases flowing and fill up with soot. Our concept recovers heat without impeding the function of the flue, which is why it's so effective. It's not actually a simple or easy thing to do.
500C is not a recommended flue temperature, put the coil or a plenum inside the stove and increase the diameter/ flow rate.
Hi Norman. It's not the flue surface temperature, it's the temperature of the flue gases. BSRIA (UK test engineering centre) shock tests flue parts to 820C, with long term tests at 500 -odd, so tested our device to the same standards as part of our CE-marking process. You could certainly incorporate into stove designs, but our device can be fitted to any stove.
So it's a flue gas cooler?
No: the coil reaches peak temperature within 3 or 4 minutes, so isn't cooling the flue because it's working at the same temperature. As it only uses about 15% of the lateral space (20mm in a 1250 or 1500 flue space) it is only interacting with a small proportion of the gases in any case, so its cooling effect is negligible. The heat recovery is still very impressive though, and at our normal flow rate stands at about .93kw of output. The big difference to the heating effect in the room though comes in the change in air flow because of the pumping of pressurised air, and the extra time the heat recovery unit pumps heat from the combustion, which is almost instantly after lighting, then for hours after the stove itself (as opposed to the embers) cools down.
@@Recoheat it's extracting according to your own figures almost 1kw of heat that would otherwise be heating the flue. I accept that might not be catastrophic but it's a consideration. I've no idea what you mean by the distribution of pressurised air - I see no ducting so I don't know how you can maintain a pressure. Do you have any engineers in your development team? It might be an idea to chat with them before releasing pseudo scientific publicity.
@@andrewbeck5547 Nice one! As you say, it's extracting 1kw of heat, but as you're not measuring the total output of the exhaust, beyond stating the principle, whether it makes a difference is based on observation. As that's difficult, although we are having it externally tested as we submit it for Hetas approval, attempting to explain the observable non-effect is hardly pseudo-scientific. Controlled lab testing will certainly give us a clearer idea, but a flue is rarely a stable environment, with atmospheric, fuel, airflow etc variables, so what's broadly observable is as true in the real world as a statement of the principle. We'll certainly be publishing any test results from the external process. And thank you very much for interest and input - much appreciated.
@@andrewbeck5547 we have wood stoves to heat houses not flues so any heat you can extract from the flue is a positive. If it means cleaning the chimney once more per year(which I doubt this small unit would even do) that is better than burning twice as much wood in my opinion
The room heat benifit is equal to the power already used by the pump. The volume of hot air is very low and will have no impact on room temperature 2 - 3 mtrs away from the recoheat
Check out the TrustPilot reviews - that's not what they say. Thanks for stopping by.
Take a look at the physics modelling video we've just published: ua-cam.com/users/shortsI6TFB8cac04?feature=share
wow nice . dose it have like a filter or something or is it hot air with smoke ? will smell the house ?
The unit is sealed from the flue, so the air going through it has no contact with smoke! Clean air, heated and accelerated, straight into the room.
@@Recoheat super awesome thank you so much for the reply , will be ordering one on the near future
Genus, cool down the air in your chimney! What could go wrong?
That would be difficult to detect, wouldn't it! It's a much tested, and much discussed point. The flue gases are not restricted - and in fact the turbulence induced by the coil shape decreases the pressure on them. The heat extraction on them can therefore only be defined by the surface area presented by the coil. This totals an equivalent area of 10cm additional single skin flue height on a 125mm flue, and 6cm on a 150mm flue. If your flue can't handle that variation, it isn't functioning and needs addressing, but indeed, shouldn't have a Recoheat fitted.
Does it make that hissing noise everytime its heating up?
Yes, it does. It sounds louder on the microphone but it's clear in a quiet room. It's the secret of the heat distribution - the device creates a turbulent boundary layer in the air flow that transfers heat very fast into the surrounding area because the air molecules are so excited! A slower, quieter air flow doesn't do this.
If we could hear exactly what it's like without the guitar score playing underneath, It will be louder than what we can hear on video.
BS! what would the temp be coming off the primary pipe without any active system (reco heat")? I would guess very close to the same temp as with the reco system. do a measure of radiant heat off the stack pipe w/o the bells and whistles
Of course it's going to be the same, but it's not pumped and pressurised air, so only has convection to circulate it. Check TrustPilot to see if it works: you really don't have to take my word for it.
does it work with pellet heaters , the flue is lot smaler
It doesn't work on balanced flues - they have different regs. If they're not balanced it will work, but you might need an adapter. The smallest we go down to is 5" - 125mm - in order to manage the air flow and the proportions of the coil in the flue.
View our Trustpilot reviews at uk.trustpilot.com/review/recoheat.co.uk
We've put up a video answering the most frequently asked questions and giving an update on what we've learned from customers over the last year at ua-cam.com/video/fOdsE-DVGTo/v-deo.html
The video about our attendance at the Guild of Master Chimney Sweeps trade show in Feb 2022 is ua-cam.com/video/55qfVfGUBjQ/v-deo.html
I'm not sure your set up will comply with Building control or Hetas.
Well, naturally we're sure it will comply with building control or we couldn't sell it. It's CE marked and externally tested for that reason. It's not approved by Hetas because they don't even approve chimney cowls or catalytic converters, but it doesn't need to be: that's not their role.
Absolutely beautiful technology, love it from Canada very well explained thankyou.I would love to see the science.
Thank you very much! We've got a couple in Canada now, and ship direct. You have proper cold!
@7.18 you say 'you get such enormous fuel savings'. I think you mean to say more efficiency from the same fuel. But, this gadget requires the use of more energy in the form of electricity to run the air pump. I can see it is a good idea but adding a complication to what is a simple and effective way to produce heat in a primal way.
That's true of course, but you cannot produce effective heat from 37w in any other way: certainly nothing like 1kw. It's also not particularly the increase in heat output that is the big difference - it's the heat dissipation. The difference is akin to having a central heating boiler running without a pump on the system: same heat produced, with almost zero effect on the effective heat distribution into your home. Our device addresses that issue.
@@Recoheat 'same heat produced'- clearly not. Without a pump, the system would not continue running. The boiler temperature would be maintained, but flow would not take place. I think you are confusing heat with temperature- a schoolboy error.
A superior design would use the Peltier effect to power the pump. This is already done with some fan units.
@@Tensquaremetreworkshop The same heat would be produced, but would dissipate via the flue and in the immediate vicinity: you can't make the burner produce less heat. It switches off when the pump doesn't circulate the water, because otherwise it would overheat, which is a separate issue to the point I'm making.
@@Tensquaremetreworkshop Yes, that's quite true, but there isn't a cost-effective means of producing one that will achieve the flow rate to create the turbulent barrier layer in the airflow that we require to achieve the efficiency of heat extraction. The lower flow rate would not create the jet we need to create the air flow into the room and draw the stove heat with it, would not pressurise the air so that it can be dissipate as the pressures in the room equalise, and by running through the coil at lower temperatures, would produce a cooler coil which would cool the flue gases and encourage deposits in a way our system prevents because the majority of the coil is carrying hot instead of cold air. It's a really interesting phenomenon we're producing, and we're exploring how to improve it, but a significant reason for using the pump, and that particular pump, is the balancing of output and cost. Thanks again for your interest.
I would only use something like this on a rocketstove with secondary burn......i doubt that little peashooter of a stove gets hot enough to spare BTU's from going up pipe to not cause creosote
That's the importance of independent reviews on TrustPilot: it works, even if you don't interrogate the physics.
Pumped, fine. From where to where...?
From where ever the pump is - somewhere you can't hear it, preferably - into the back of the unit where it connects to the steel coil inside the flue and travels around that and out at the front of the flue.
Where does the power for the pump come from? Also concerned about condensation.
Sorry - missed your comment. The pump is a 37w electric aquarium pump. The unit doesn't generate condensation, and actually removes it in the boat we've got it in, because the warm air picks it off the cold surfaces and carries it out through external vents.
Not clear at all. Need a diagram to show the operation of heat recovery unit.
How many hour the heat remain in room if fired for one hour
It depends on the stove (how heavy it is, so how long it retains heat for) and the type of fuel burned (how much mass of embers remain hot after the hour) but certainly for five hours and probably for eight and more. Think how long the embers and ash remain hot for - a proportion of that heat rises up the chimney, even when it is not sufficient to heat the stove. It is reclaimed from the flue by the Recoheat and circulated. It will be pumping at about 30 degrees whilst there is any heat in the embers, which will keep most rooms warm. It's so effective because that heat pumps even when there is not enough heat to produce convection that normally circulates the warmth from the stove. There is a test like this published on the website - www.recoheat.co.uk
if you can power that air pump from the heat produced on this stove and do a schematic video I think everyone would be happy; and also I think you have to figure out a way to make a device that a normal person could install, because some installers have only got the £ in their heads and not the service sadly..many go to youtube to save money and improve what they have got, not just “look buy this, because it’s doing this”… 👍✌️
Yes, both would be wonderful. The latter is largely regulatory, though there's a very practical issue of ensuring something as dangerous as a flue is maintained competently. The former will take a lot of engineering development, so is expensive so requires lots of sales, or investment.
Not clear even with the basic diagram on your webpage.
Im guessing it's an approximately ½" pipe passing through the stove pipe which acts as a heat exchanger.
Room air is passed through the pipe from the air pump.
Hopefully the portion of the heat exchanger pipe inside the stove pipe is wound in a spiral to allow brushing.
IMHO better if the pump used peltier or at a Premium a sterling engine technology rather than MAINs electric and its associated inefficient properties.
Further as an after market kit I'd prefer a helix of pipe (spring loaded) which could be diy wound around the outside of the stove pipe etc
Have I got this wrong?
Anyway best of luck.
Thanks for your interest Nick. In fact it's a 2m coil of 10mm 316 stainless, so pretty close. The pump and coil disposition create a turbulent barrier layer in the air flow that creates the efficiency in heat transfer, and we currently can't create the necessary flow rate to achieve that without external power. It's something we're looking at though, so watch this space!
Sorry but my stove requires a 5" flue. If I add this that is a restriction to flue diameter.
About half our units are in 5" flues.
What happens if the pump stops working?
Nothing: the coil is made of the same material as the flue so it's not affected.
How’s it work where’s it pumping heat
Out of the pipe outlet just above the collar of the stove, at the front.
I've absolutely no idea of what you're talking about. No idea of what the device is, where the air movement is, what's inside the flue. No idea if there's an electric fan in the flue, where the air's coming from, where it's exhausting to - indeed, no idea at all.
Website is www.recoheat.co.uk for more info, if you're interested.
Does the oxygen increase fuel usage
No, because the air going through the system never interferes with the combustion. It's completely sealed from the flue or the stove, so has no effect.
Where does it pump to because it never showed. Very interested but of course still very novice.
Hi Jimmie, it pumps into the back of the unit, around the coil, and out the front. The unit is in the bottom of the flue, and fits into the flue collar.
@@Recoheat 👍
37w light bulb?.... I remember those days before we all went LED, that's ten light bulbs now... Lol
Sorry couldn't resist, good luck with your product 👍
Thanks mate. Yeh - you have to be past the 'energy saver' bulbs burning at twice the pace and using 2/3 of the wattage! Long live LEDs
Is that loud?
It's not loud, but it's clear. Not as loud as a fan heater, for example.
May I suggest that you review this ad with someone unfamiliar with the product. I watched and have no idea how your product works. You point to the hot air coming out but I see no means for the air to escape the unit. There is no illustration of what the construction looks like. There is no mention of the materials are or what the warranty might be. The air pump is delivering 1 liter per second. That sounds substantial but in fact it's really not. 2 CFM is next to nothing. On a a good day could this thing deliver more than a 1000 btu?
Thanks very much for your interest and very fair comment. You'll see that we've developed the presentation and explanation over the course of the last couple of years in a number of videos. The effect this has is to strengthen the number of people coming to this original video! It's fantastic at driving traffic, but as you say, means everybody gets to see the earliest efforts at presenting the product. Despite the weaknesses in presentation and the poverty of the explanation, the one thing we did know at this stage is that the device does work, and all our subsequent development in experience and understanding has confirmed that. Do take a look at our TrustPilot reviews because it sort of gives the opposite end of this video 0 the experiences of customers using it over the last months since we launched that process. Thanks again.
You're confusing temperature (measured in degrees C) for heat (energy measured in Watts per second OR commonly BTU/hour).
Thanks for the engagement Justin. That's probably true, though this isn't an engineering piece, so we're really trying to explain it to potential users. It's effectiveness is certainly more down to heat transfer rather than the temperature, as you say, which is so efficient in the coil because of the turbulent boundary layer we create with the pump. It's very interesting stuff.
And you're confusing the definition of heat flow. It's watts, or joules/sec, but not watts/sec.
@@realmetallurgist8493 It is the number of joules from a given mass of fuel that you are interested in. That gives you the thermal efficiency. The claim is 'twice the heat from the same amount of fuel'.
To be honest I could not see how it works or what advantage it has.
See the website at www.recoheat.co.uk, or other videos on the channel. Thanks for your interest.
I don't understand why you wouldn't just sleeve the flu and run a simple metal fan arrangement to blow a much larger volume of air through this comparatively much more efficient solution. The low volume of air here means that even though it's very hot, surely the heat transfer is pretty low
The cooling effect of the devices like this is far greater, and the energy expended in driving the fan is greater, while the heat doesn't travel as far. We're essentially putting the electrical energy into pressurising the air, which then distributes heat as the pressure between the warm airflow equalises with the cold areas of the space. It's like the difference between pumping water on a level, and pouring it down a slope. That's what explains the fact our units heat to the floor and transfer heat so far, as attested by customers in all sorts of designs and build materials in their homes.
That chimney stack from you're stove, retains lots of heat and disperses it throughout the room. Are you not drawing this valuable heat source away from the flu. Chimneys in General act like storage heaters still giving off heat many hours after the stove has cooled.
You are taking heat from the chimney for very little gain in my opinion. Also a cold chimney will have tar build up on the flu leading to chimney fire. Also a chimney with tar build up is much more difficult to clean .
Thanks for the interest. Just take a look at our TrustPilot reviews and Facebook comments to see if your views are true: the wonderful thing is that we don't have to argue it. Explaining how and why your perfectly reasonable and rational perspective is not correct was more difficult when fewer people had experienced how it actually works. That was previously our difficulty: sharing the fact that it does. Which was hard, because it does. Our units, on a 5kw stove, are heating 2 bedroom houses. That's silly as a claim, but remarkable as a verifiable statement.
Can that be used in a house?
Yes, it can: at the time the video was made, we weren't CE marked, but we completed that process shortly after so that it meets the regulations, and is thus being used mostly in domestic settings and can be fitted by Hetas etc registered fitters.
OK thats a good idea. But I have a couple of questions for you.. how much faster does the wood burn so you have to reload with more wood more often??? Wouldnt it make more sense to use a ceiling fan or put a fan close by the stove to push the air around?
The air being pumped does not enter the combustion chamber, so does not affect the burn rate. Some points about the air coming out of the unit are that it is turbulent, so it transfers heat far more efficiently, and is pressurised (by the expansion caused by the rapid heating) so that it creates a convection flow out of the heated area as the pumped air equalises with the air in the room. It also comes out in a jet across the top of the stove, which draws the radiant heat from the stove behind it. It is also heated itself, so adds to the heat in the room. So the effects come from a number of factors, and achieve a great deal more than just moving the radiant heat with a fan. 👍
@@Recoheat how can you ignite fire. I know you can ignite wood and other items but not fire.... I thought igniting something turned into an explosion, catching something on fire or along those lines
@@mitchellchandler3689 No Mitchell: ignite just means to light a fire.
@@Recoheat and watch the video and listen to what you said.....
@@mitchellchandler3689 Aah! Misplaced pedantry! If you can light a fire, then a fire can be lit, and can be a fire before it is lit. The word is also used to denote the object within which a fire is set. It's Aristotelian, even Aquinian perhaps, but common English usage. I salute your concern with niceties, but the distinction applied is a false one: English has a beautiful way of shifting the subject and object to create new nouns, and verbs - it's why it's such a good language for poetry, and why legal documents are so lengthy: you have to make a great many definitive statements to preclude so many possible meanings in the simplest statement! 👍
Quote from website 'use half the fuel for twice the heat output.' Given that a modern stove is ~80% efficient, how is that possible? (320% efficient...)
By running it for four times the burn time, and producing a pumped output temperature that regulates the room temperature sufficient to warm it and prevent a temperature drop that takes lots of heat to redress. That is the key to the efficiency - not simply heat output, which is minimal compared to that of the stove itself. The device works by driving the heat more efficiently, and without the necessity for convection, which in turn obviates the necessity to have a consistently high radiant heat output from the stove.
@@Recoheat I repeat- the efficiency of stoves is c 80%. Length of burn is irrelevant, it is the energy content of the wood vs the heat output of the stove. You are claiming 360%!
@@Tensquaremetreworkshop No, it's not! Who cares how hot you fire is, if there is no heat distribution! You appear to think that the purpose of a domestic heating system is to create a jet engine in a small hole. The definition of efficiency is to use the least to greatest effect. Our device strives to achieve that, and it does so by exploiting a specific of thermo-dynamics that is being used widely in industrial applications but not in domestic, because it is generally too complex and expensive. We've made a significant bridge in application. If you doubt the science, that's fine, but is simply down to ignorance: it's effectiveness and reality is incontrovertible. Whether we're applying it effectively is down to our own effectiveness, and proved above all by our customers. I quite understand and appreciate your incredulity, because the physics is not logical - but it is real. Go and research it - or just look at the difference it does actually - not theoretically - make to people using the device.
@@Recoheat Let me make this as simple as possible. If I have a piece of wood that contains 1MJ of energy, a modern stove will allow 800KJ of that to be used to heat the room (80% efficiency) regardless of whether I do it slowly or quickly. The home page of your website claims to to produce 'twice the heat, for twice as long'- that amounts to 4 x 800KJ = 3.2MJ of energy. Would you care to tell us how you get 3.2MJ out of a 1MJ log?
@@Recoheat I am far from ignorant- I am a Consulting Engineer, and I often have to spoil the day of clients who have come up with a scheme that unfortunately defies the laws of Physics. I have studied thermodynamics (at degree level) which, from some of your comments, you have not. An example- the calculation of heat transfer on your website is incorrect (by a factor of 2), due to miss-applying the formula. I have left a note there explaining the error.
Can you please tell me the grade of metal that is used inside the flu pipe ??? Thanks
316 stainless as required by the regulations. We're CE marked and compliant under the standards for a rigid flue section. Thanks for the interest. If you've any further questions, do get in touch via the website www.recoheat.co.uk
@@Recoheat Thank you for a quick response Sir.
I will purchase one this coming winter. Thanks
@8Truth Seeking Sounds like you just need to renew the fire cement. Otherwise, I'd recommend getting someone qualified to look at it - and make sure your carbon monoxide alarm is working in the meantime. If you can smell leakage, it definitely needs sorting because the flue should have a negative pressure - so it should be sucking air in, not letting it out. If it's going the wrong way, it'll be because of the air pressure because of external temperature, or you've got a blockage, or your flue isn't high enough. Definitely get it checked.
Who lights a fire then shuts the door whilst it catches?
I have 2 meters of single skin flue on my fire, it radiates heat within minutes to be honest. And the single skin is much cheaper than the twin wall so money already saved..
It's funny to watch something working in fact, and pointing out it doesn't work in theory. Wouldn't logic dictate you changed the theory?
Good way to have allot of creosote build up in a chimney especially if you are not running it full bore all of the time. Possible fire hazard. Also, fyi, you can do this just as well without an air pump.
High temperature of the coil and the von Karman vortices it induces prevents build up of soot on the coil in a healthy flue. Also, fyi, it plainly doesn't. If it did, when we switched the pump off, it would function just as well, so we and every observer, engineer and customer would have to be pretty bloody stupid to persuade ourselves that it did.
@@Recoheat Stop replying to these incognito eco psychos and marketing henchmen. You have made an amazing product. A retrofit heat pump that blows away any “renewable” solution at a fraction of the cost.
Many HVAC CEOs of some of these expensive boxes will be sh*tting themselves once cost-of-living syncs with their annual projections. They might lobby for a ban. Good luck mate.
That video didn't really tell me anything, so they pump air in which makes the fire burn hotter and quicker so it gives of more heat. Maybe show the insides so we can see what this magic thing is or even show the fire working without the pump so we can compare the results
No - we don't pump air into the stove or affect the combustion in any way. It's a sealed heat exchange unit using turbulent air to transfer heat more efficiently.
@@Recoheat He said it is a sealed unit with an air pump, so how does that work then ?
PITY THE STOVE ISNT FITTED PROPERLY
TOO CLOSE TO COMBUSTABLES AT SIDE AND REA
It's fireboard at rear. I think it would be fairly obvious very fast if pine was getting too hot!
@@Recoheat funny looking fibreboard at the side
I love the stove you have; can you tell more about it; we Americans have no taste and we are using 200 years technology and design
That's a little Ecosys 5kw: works really well and costs about £400. There are a lot of beaurtiful stoves around, but it's one that is very good quality for a low price. With the Recoheat on, it kicks out masses of heat across a wide area.
why so low a temp. My ho use is 72 degrees F.
It's a timber cabin, so maintains no heat overnight unless it's being heated.
How do you put stove pipe through roof
You need to be using twin-skin flue pipe. Cut a hole with 50mm clearance around, put a ceiling bracket in and put the flue through to whatever height you need for your roof and draw. Fit a rubber seal/cap on the outside, which needs screwing and sealing. Then fit the roofing felt over-lapping the edges. On the inside, you then fit a sealing plate to cover the hole.
interesting to see an old idea revamped. however the reason they stopped doing those systems is cooling the flue gases increases soot build up and the chimney clogs up rather fast. of course its impossible to heat the room more than normal without taking more heat out of the flue, conservation of energy and all that good stuff.
Thanks for your interest. It's interesting to hear your reference to other versions: can you be specific? We've found absolutely none. There are plenty of examples of convection and fanned air systems, and there are examples with water, but we've not found any using forced air and the turbulent boundary effect. This is our first video, and isn't the best explanation: our other videos give more accurate descriptions of the process and feedback on the device's real-world use over the last years. Both of the issues you raise are valid concerns, but don't actually occur in a healthy stove and flue system, principally because of the coil shape, which creates turbulence and so decreases flow resistance, and because the coil is being heated by the hottest part of the flue gas flume only in relation to its surface area which is very small relative to the flue itself - the equivalent of an extra 10cm on a 5" flue, and 6cm on a 6" flue. As the range of flue lengths any stove has to contend with - between 4.5m minimum to at least 10m on a domestic system - this increase cannot legally be enough to effect it, or the stove can't be sold.
@@Recoheat you missed the point. taking extra heat out of the flue makes it soot up more. with gas fires its fine because they burn clean and thats how efficient gas boilers work. i ran into it many many decades ago and it was ancient history then. i can't point to any details as its pre internet.
one of the setups i've seen in use is a fan blowing along the side of the firebox in a duct as you don't have to worry about the firebox sooting up so much.
@@tweake7175 With respect, I'm not missing the point, I'm saying it's not so: it doesn't soot up. I'm merely trying to explain why, but not arguing whether it does: it doesn't. It is a very obvious thing if it does, and if the stove is badly configured so that the bottom of the flue is not hot, then it can, which is why any potential operators have to check that the bottom section of their flue is clean in normal use before fitting. As such, it has the same operating conditions as a chimney liner and is no more likely to soot up. All flues have operating conditions and all flues soot up if those conditions aren't met: our device operates in identical conditions. The science of why our device works better than a fan-based system driving laminent air over the flue surface is interesting, but the difference in effective heat dispersal is enormous. Do take a look at our other videos etc: this is a genuinely effective device because of a genuinely innovative system that seems simple, but is actually not. Thanks again for your interest.
@@Recoheat Is this using any type of catalytic burning of the exhaust gasses? If so, that would completely counter "tweake's" argument of increased soot. Some newer wood burning stoves have a catalytic burner to burn the soot and smoke. Free extra heat and almost NO soot in chimney. But they are newer and have been a bit price prohibitive for my budget!
@@agentmacguyver2974 We have our own physics to stop soot accumulating on the flue but are looking to combine with the Puriflue Midtec catalytic converter to create a product that's even more awesome!
this 24v?
No, it's 110/240. It'll run off a 12v battery with an inverter - we've got a demo one on a motorbike battery.
I have absolutely no idea what your device is supposed to be doing or why I should buy it. Sincerely
Sorry! If you're interested, the website is www.recoheat.co.uk. There are clearer videos on the channel, listed in the notes. Thanks for stopping by.
It would be nice to see the pump and placement etc.
Yes, sorry: this was pretty much our first video and leaves a lot to be desired! This one gives more info: ua-cam.com/video/fOdsE-DVGTo/v-deo.html Also obviously lots of info on the website at www.recoheat.co.uk
It's not clear to me what's going on. Pls add a diagram as to all the components and how they work
Check it out at www.recoheat.co.uk for diagrams etc. An air pump is pumping air at 1 litre per second through a sealed heat exchange unit in the flue, just above the stove. That heats the air to about 500 degrees so it expands and is expelled at about 4 litres per second. That jet of hot air draws the heat from the stove away with it and creates a much larger heat exchange area in front of the stove, and produces a positive pressure in the room that also moves the air away from the stove towards the edges of the room or out of the room - because it's higher pressure so replaces the lower pressure colder air. It therefore works in the opposite way to convection in terms of initial air flow, but creates a convection flow in and out of the room into other parts of the house.
@@Recoheat where is the pump inlet
@@Recoheat what prevents creosote and condensation from building on the cold parts of the coil where room air is entering? There's a massive temperature imbalance there
@@gutrali The turbulent barrier layer means heat transfer is largely complete through the vertical section of the coil. The air then descends into the hotter section of the flue. Little of the coil is cool therefore. The physics is just not the same as that of a laminar air flow.
@@gutrali On the back of the flue section
I'm just saying for normal lighting my biggest bulb is 8w.
Ah, the youth of today!
@@Recoheat I'm only making that point because I dont know anybody with old school incandescent bulbs. Dont get me wrong though I'm super intrigued by the product and am seriously looking into it for this next winter.
@@silver1fangs I'm being facetious - it's just an age thing. When we moved into our current house 15 years ago, we had probably 2000w of light bulbs, which is now about 100w.
Is this unit available in Canada?
Absolutely! We ship direct from the UK and make a £25 charge towards the cost. It doesn't actually take very long. The pump works at 110v and we now include a US plug adapter.
Not convinced, no details on installation or cost
The website is www.recoheat.co.uk for price details. Installation depends on where you are and where the stove is, insomuch as you need a competent person like a Hetas engineer to fit them in a domestic installation in England and Wales, but can do it yourself elsewhere. You need to be competent not so much for the fitting as for checking your stove and flue are working correctly: the bottom metre needs to be clean which shows it's hot enough so that the Recoheat will function correctly and stay clean.
Do you ship to Canada?
Hi Santo, yes, we do, and in fact our pumps do work at both 110v and 240v, so we can supply them too. We charge a £25 contribution to shipping costs.
I didn’t hit dislike, but You didn’t explain it in a way that I understood.
More info at www.recoheat.co.uk - thanks for the interest
That's well noisy, it would get on my nerves, same with a pellet burners, too noisy
I think that was the air rushing past the thermometer rather than the fan itself.
Who makes that wood stove?
It's an Ecosys from Stove World UK
An update. I have traced the manufacturer of the air pump, and the flow is rated at
The pumps are designed for use in fish ponds, to run 10 outlets, all venting through stones into water. It is therefore designed as you say for a pressurised outlet. Our system has the silencer, which has an indirect baffle so does not directly impede the air flow, and otherwise accelerates the flow, so reduces rather than increases the pressure. There is no constriction on the airflow, so no pressure on the system, which in fact has successfully run on people's systems since 2014. They do wear out eventually, but are very robust. My current one has been running since 2017 with no problems. There are certainly better pumps available, but the one we use seems to be the best balance of power, reliability and cost.
@@Recoheat As previously explained, the thermal expansion of the heated air pressurises the tube. Calculations give c 1.5 bar for this. Try calculating it yourself. Hint- the acceleration of the air (faster out than in) results in an opposing force; F=ma. Of course this is if you were getting 1l/S. Which you are not- the pump is not powerful enough.
@@Tensquaremetreworkshop How can it pressurise the tube when it's moving out of the tube, unimpeded? The thermal expansion causes the air to accelerate - it's got no force acting on it to allow it to build pressure. You can very clearly hear, see and feel that, both as it heats and cools.
@@willburrows It is the movement of the gas that causes the pressure! Newton's third law. If this is difficult for you, consider the rocket. Gas burns, expands, and is expelled out of the rear, and the opposing thrust of this propels the rocket forward. In a fixed system such as this, the result is pressure against the pump. The calculation is very simple (even though it is rocket science!).
I
@@Tensquaremetreworkshop This is the engineer and technician argument, no one will ever win. I don't think people are being disingenuous, if an aquarium pump provides enough air to make the thing heat a larger area quicker and it works for long enough to make the cost of the pump and inconvenience of replacement worth the investment then it works just fine. An engineer can find a better pump, at an almost certainly higher cost, but from a practical standpoint who cares?
you did not explain the heating supplement system mechanics???? Why? You were interested in reading the heat in the flue and what and how it works, show a unit out of the flue, and showing the compressor in the back of the wall???? Your report is all pictures and not a very large sum of mechanics on how this works please
Sure: it's not about the mechanics. There is a lot of information on the website at www.recoheat.co.uk. Mechanically, it's actually simple; the complexity is in the physics. Thanks very much for your interest.