Hmmmm

I thought about that

I want to try that then you wouldn't need a pump also

Of course I did mean run the exhaust PIPE through the water and not bubble the exhaust gasses out through the water 😁

@@Yeoblade yeah in threw one side out the other just the pipe in the the water

Thanks for the reply Mel. Regards Peter

Thanks so much for getting back to me as it makes what I did so worthwhile. I always try to look at things with a KIS= keep it simple. - Generally works but as you could see by my first effort with the radiator it doesn’t always work - I feel on the second video I cracked it because it followed the principal of KIS so well. Again thanks for getting back to me and stay warm and stay safe. Regards to you. Peter

@@brucepeter2007 We both had the same idea to heat water with the excess, but I have to say, your idea is actually much simpler. If you have a water tank installed it would mean you have to run the heater a lot more, presumably even more then necessary, just to get the water tank up to temp... And it would be useless in the summer, or most of the year... That said, I am thinking about building an off grid shed - totally off grid in the mountains, so maybe in a situation like that... but really, your way is versatile - perfect. Brilliant, thanks for the videos!

Hi man stuff. Lots have used the video experiment and adapted it to suit their own installations so if it helps have a go as the results are very good when the pipes to exhaust are insulated and I’ve been told the water gets up to near boiling. Thanks so much for your comment. Stay safe. Regards Peter

Try to just put exhaust pipe threw the bucket then you don't need pump

Hi KLH. Many thanks for your kind comment and glad the video has sparked some interest over the pond. I am sure others will have a go although I have not yet had any confirmation of it yet - once the video catches on over there I’m sure it’s simplicity will prove useful to making a good working system as why throw that heat away! You have paid for it🤔🤔🤔 Regards to you sir. Stay warm. Peter

Hi Per. I have to say I took it as far as I wanted to just satisfy my curiosity as to how much heat I could recover and I was well pleased with my crude set-up as it worked better than I ever expected with the small copper coil. No insulation to keep the heat in and I could have improved it no end with an even longer length of copper pipe to milk even more heat out of that exhaust... My intention of posting the video was to show what you could do and the off grid lads will no doubt improve on my meagre experiment which is what it’s all about on KZfaq - help and enjoy. Regards for your comment. Stay warm. Peter

Hi Scot. Thanks for the comment and valid points - I was aware of the pump and flow direction issue but as this was mostly an experiment to get the bee out of my head on the best way to recover the heat I did not take it further however I have had loads of emails and helped many out who have installed the system on both RVs and boats but it would be nice to see some other videos of how people have done but alas to date I’ve not seen any. If you do use the concept it would be great if you posted a video of your installation and the results obtained as with some good insulation I think the heat recovery would be very impressive. Stay safe, stay warm. Regards Peter

Thanks for the comment Stephen. Regards Peter

Hi there. The idea was to use the free heat during cold periods instead of throwing it into the atmosphere and this is the second video experiment I have done and this shows that using this system can work quite well - especially if you use 9 meters (30feet) of the copper tube. Circulating to a hot water tank would provide enough stored water for a shower and the return after the hot water tank could have the copper tube pass through the cold tank thus providing just enough heat transfer to prevent freezing. The possibilities are all there for anyone to have a go at. Thanks for your comment - stay warm. Regards Peter

Hi juniper - yes a gravity system would work with an expansion tank however the design parameters in a small van for the required correct runs to get it to kick start would be very hard to accommodate so a small pump with very low electric consumption would I feel be the best way to go. BUT give it a try if your so inclined and let us know as it’s an interesting topic. Regards Peter

​@@brucepeter2007 Another thought: Have the tightly wrapped copper tubing 'be' the exhaust pipe...no additional center pipe needed. Thus, it would have direct contact...with the exhaust gases (passing through the center space of the coiled tubing). This 'heat exchanger coil' could also be soldered/brazed for maximum efficiency--so it wouldn't leak any gases between the coils. The cooling water (passing through the coil) should also keep the solder joints from ever melting or failing.

@@JuniperTrekker hi again Juniper. I have to say people have suggested many variations on the theme but as yet I have not seen anyone else try anything yet on KZfaq so if you want to try please do. One if the issues with these little heaters is that the free flow of gasses is imperative and the tube lengths and number af bends is critical to there proper working so there are constraints. By using the simple copper wrapped coil I used everything was simple because you could even remove the exhaust and leave everything in situ while you worked on the removed unit. I only played about as I was keen to see if anything could be done easily and it can so I would guess some have developed it to a higher degree and mine was kept simple with no insulation and the test performed with an open bucket and no insulation on that either so imagine the result with the same system I made but with plenty of insulation... The mind boggles... Regards Peter

Hi Toll. Thanks for your comment and some interesting points raised. When I proposed this method I can honestly say I never envisioned the widespread use the idea could be put to and under such harsh conditions to boot! I will try to helpful in my teply

CONTINUED... Regarding the fuel consumption - I feel that the extra fuel consumption you mention is not a result of the exhaust heat exchanger because the whole idea of this system is heat recovery - which is the surplus heat which would otherwise be ejected by the exhaust after the burning process within the burn chamber - this unit is in truth a “furnace” so has strict parameters it can work within so the extra fuel consumption you observed would be down to other factors or altered settings because the fuel to fan speed air mixture has nothing to do with the design or result of the heat recovery method design... One other thought has come to mind - have you changed the length or bends on the exhaust as the back pressure could have an effect on fuel consumption but other than that I can see no logical reason the heat exchanger could make the fuel consumption increase - other people’s replies will surely come after reading this as I maybe missing something🤔 “FREEZING PIPEWORK.” This is an interesting one. Firstly the design criteria I proposed was never envisaged in a sub zero environment and this is a whole new ball game but the method of the heat exchanger working that if the water within the pipe were to boil ( pump failure or blockage) (ice)- the pipe would not burst because of the small volume of water contained within the pipe and the available heat at the exhaust I would suspect this could be true with freezing but would bow to superior knowledge from others on this. Now this is an interesting adaption of the heat exchanger and the only way another water tank could be heated would be by making the heat exchanger a closed system and have a suitable quantity of antifreeze added to the water to cover the temperatures required. By a closed system - I mean that within the water storage tank with ( I presume fresh water) a further larger coil would be required with a good surface area to transfer the hear over from the antifreeze laden heat exchanger pipe to the fresh water tank to lose its heat before returning to the inlet of the heat exchanger to be reheated. A further issue arises as an expansion tank would be needed as well. I hope my reply has been of help as your reply gave limited information but be assured many other people fear the replies so no doubt will chip in with further information that may further help you - such is the power of youtube. Stay warm, stay safe. Regards Peter

I was planning to use 3m of copper tube stuck underneath the plastic water tank of our motorhome using self adhesive insulation sheet. This rather than inserting the copper tube into the top of the water tank. Not sure if enough heat will transfer through the plastic tank but that is what the 60W electric tankblanket uses.

I'm going to fill the pipes with a 50% solution of antifreeze. Problem solved.

Hi there. Many thanks for your kind comment. Like me you thought the same regarding the lost exhaust heat so I did a few experiments - less said about the first video I made the better - except anyone want to buy a dual banked small radiator, I digress.. My final goal was reached with this system as all the bits can be funded anywhere and can be added by anyone easily to get a good working system. KZfaq is always interesting to place such ideas as there are loads of inquisitive people so it’s a great site to get help and ideas. Again thanks for taking the time to send me a reply. Stay safe & stay warm. Regards Peter

I’m pleased the video has been of help. Just a few points - closed system is not ideal as it’s better to allow a little expansion tank 🤔 just saying. Good luck. Regards Peter

@@brucepeter2007 1mm or 0.6mm copper pipe? The latter is cheaper. 15m refrigeration 6mm tubing 0.7mm wall is £33 incl delivery.

@@TheAce5255 I said in the video 6mm which gives a good flow and is a durable size and easy to work with and gives a good flow. Your choice what to use as I only plant the seeds… Good luck. Regards PETER

@@brucepeter2007 Yes, I meant the wall thickness. 0.7mm might be easier to bend. Also, what about filling with sand first, as some videos show?

@@TheAce5255 Hi Andrew. In answer to your question about filling the tube with sand I never wanted to do this. The copper tube is already annealed and bends easily and the trick is to have a good former which is at least the same diameter as the exhaust pipe. You bend the copper pipe around the former and the side in contact with the former actually flattens and thus you get a better heat transfer… Removal from the former is simply holding the bottom on the copper tube and unwinding the stress on the coil at the top of the copper pipe and the former will then fall away. I tried to keep everything simple so people on different continents with different suppliers could adapt and still get the same results… I hope I have answered your question fully. Regards Peter

Hi Lyons. Thanks for your valued comment. There are many issues to consider with this type of heater and one of the issues is that you have to limit the bends in the exhaust to allow the burnt gasses free movement and quick exit else the heater has a real tendancy to soot up requiring a total strip down when this happens. The length of the pipes on combustion input and exhaust ideally need to be the same length if posidle to keep the pressure difference about the same. The systems combustion air induction / exhaust can be extended but that would then require the mixture to air ratio to br “tuned” which is where most people go wrong because playing with the settings usually requires special expensive equipment which the majority of “twiddles” don’t have and they end up with soothed up units requiring a total strip down and lost original working settings... As you can see from the brief explanation above I have given there were many reasons I experimented the way I did because the whole idea was to be able to extract the heat simply with parts obtainable at little cost almost anywhere and also to ensure the basic working system of the heater remained untouched thus not affecting its performance. The other point I kept in mind was that if the heater required services the attached additional pipework would not add any extra work to the units removal which I hope I achieved within this design experiment. Thank you so much for your valued comment which I hope I have fully understood and replied to. Always great to hear from like minded people when it comes to ideas so thanks again and stay safe & warm. Regards Peter

@@brucepeter2007 many thans for you reply. noting better than content creaters that activly reply and engage with the commenters and viewers. look forward to more from you too. i did stumpble upon a different channel last night. same concept of harnesing wast energy into heating water. he was using a egr cooler from an old car from a scap yard cost him around £10. sounds very promising from the footage and the egr heat exhanger looks the part too for a repurpased componet. mabe werth a watch if you not yet seen it bud

Hi Lyons. I was aware of the EGR unit but even though you can get them you need even more ingenuity to adapt it to the heater and extending the exhaust can prove to be a problem with sooting. The reason I went with the copper coil was pure and simple “simplicity” and this also encompassed having to remove the unit for a service without any other water complications from the simple heat exchanger. Others can modify on this experiment and hopefully post on KZfaq which will give me the utmost pleasure to see. Regards Peter

Hi Jason. Thanks for taking the time to reply. Stay safe and a happy new year to you - at least a lot better than 2020 has been. Regards Peter

@@brucepeter2007 stay safe

You can now see it works so have a go. Regards Peter

You could could probably gravity feed it from the bottom of your tank and the pressure might feed it back into the top might need a pressure release valve though lol

Best to keep the pulse pump - very low current and keeps it simple as a gravity system is not straightforward in an RV or boat and could be more trouble than its worth. This way it works - always. Everyone can modify it to their needs but at least in winter when your heater is on you can stop your cold water tank from freezing up and even get some free hot water. Better to use the heat than throw it into the atmosphere. I’m not green but I don’t believe in waste if I can help it. Thanks for the comment as the more comments the merrier. Regards to you. Peter

Hi there - Its all on eBayand this is the link which I hope will work. .Regards Peter www.ebay.co.uk/itm/12V-ELECTRIC-UNIVERSAL-PETROL-DIESEL-FUEL-PUMP-FACET-POSI-FLOW-STYLE-CAR-VAN/231590429385?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2648

Hi there. Your question is a strange one because why would you want to produce boiling water! If you require that even a domestic water heater could not supply it. The whole idea was to recover the heat and use it in a useful way like heating a store of water which could be used for many things - even to stop a water tank from freezing. There are many applications the recovered heat could be used for to save throwing it away - after all you've paid for the heat so a great shame to just pump it into the atmosphere ... Regards Peter

Peter Bruce thanks for your answer, I am produicer of apple juice in mobile line, and I want create hot water with my generator for pasteurisation with my exchanger

@@jean-damiennoiret3473 Hi again. Sorry the idea an not help you but it seems that to produce the boiling water you require would need a lot of heat input and this little heater was originally designed just to heat a lorry cab so you can see it falls way short of what u would need. Good luck with your search. Regards Peter

Peter Bruce thanks Bruce ;)

Hi Toby. My approach was for simplicity and ease of construction together with not causing any issues by the introduction of any additional bends or making extensions to the exhaust pipe. The ERG unit is very valid but can cost and it’s not as simple as the copper pipe but if you had one going for free and doing nothing then it’s a good move. I did both videos as I was interested in seeing what usable heat could be captured and the video was a steppingstone for others to build upon which (all credit to you ) a lot have done. Many thanks for your valued comment and if you have a working system on video please let me know. Regards Peter

Hi there. Thanks for making a comment on my site. Felt I should leave a comment for a year till you did retire - so IF you’ve retired now you will have found you have even less time to do things than when you went to work! Hope I haven’t burst your bubble🙂 Stay safe in these fragile times. Regards Peter

Hi George. You are restricted on the length of exhaust pipe you can use due to back pressure and soot build up. Also the way I have done this means it can be stripped out without any complicated issues.

Hi Nate. Thanks for the comment - the video I made was for a start position for anyone contemplating having a go and also to see what usable heat could be recovered. EGRunits come in all manner of shapes and sizes which means you have to be more adapt to use them and of course have the space to install them. Regards Peter

Hi there. Thanks for your comment but my bubble is still intact. The Chinese did start to market the combined heater / water units AFTER I made my video and check out the price - arm and a leg job . If you look on the Chinese Diesel Heater forums you will see many guys in trouble for many reasons asking for help on maintenance. With my design the unit can be removed by just undoing the existing clips you would normally have to remove to remove the heater from the vehicle - nothing more. With the unit which has the water section built in you also have to remove the 2 water hoses (remembering you needed to install on/off taps on each extra water pipe close to the heater)) so you can remove the unit for cleaning or maintenance without draining down your water tank... When I first looked at the design I took all this into consideration to keep it very simple and cost effective and able to acquire the parts needed almost anywhere. Each to their own but simplicity, maintenance and cost were my major objectives. Stay safe. Stay warm. Regards Peter