I just made one of these but modified it to 4 ft x 8 ft and was able to get almost 500 ft of tubing in it ( actually 480 feet ). Very heavy so I added two heavy duty wheels. Warning : Do NOT try to stand up after running water through it……. the weight of the water in the tubes is a problem maker. Working on coming up with an Air Hose to plow the lines out before standing up. First day using mine , outside temp was 81. Filled the pool up with 72 degree water. Water came out of my devise at 86. Only getting 6 hrs of Sun so will takes a few days to get pool to 85.
Hi, this one of the best solutions to heating the hot tub I've seen. Well done. I'm thinking of attempting the same this summer. Could you list the parts please? I like the copper one, might use that in combination with a larger tub tank to have free showers in the outhouse shower cubical. Bit of thought around that one needed? wish me luck! cheers. Dai
Hello. Thanks for viewing. I used 10 metres of 10mm copper piping from my local wickes, around £30. The box was made of some old tongue and groove wood I had in my garage with a simple frame added. I added a piece of polystyrene to the back, on the outside to add insulation but it melted on one day due to the box reaching an internal temperature of 145 degrees.. A sheet of 3 mm perspex was used on the front. I fixed this too the frame via wood screws. You can safely drill perspex using a sharp drill, it won't crack or shatter if you go carefully. Make sure the hole you drill is one size up from the screw being used as if the screw is tight fitting, this will cause a crack upon tightening. The fixings are John guest speed fit for 10mm piping. I added a tap to slow the flow rate down, be careful as if the tap is closed the water inside the box will soon hit boiling point. My water is pumped around the system using a 400L/H Solar Panel Powered Water Pump Garden Pool Pond Fish Aquarium Fountain, bought off ebay. I have a 20ltr water container in black to also absorb heat. The feed pipe is just a short length of common fuel line. Hope that helps
@@royclark8385 many thanks Roy, I am about to experiment with both your copper piping method for a shower in an outbuilding through a tank and a solar panel powered system for the hot tub....thinking of options around including a battery and controller for a bit more consistent heating,,, ironically just before you replied I purchased a pump and heater in one which I saw on another utuber 's channel.... really excited to see all this working and saving some money... thanks again... Dai
@@cosmicdai Hi Dai, the 20ltr black jerry can is solely used with the smaller copper pipe heater, it just happened to be next the the larger one at the time of filming, its not linked in any way to the larger solar heater. Good luck with the build..
Hello, thanks for taking the time to view and comment on my video. Sadly we have not had the hot tub out in the last 12 months, hopefully this year we will have an opportunity. Although we are soon starting a campervan conversion so it will either be put aside once again or a welcomed break in the evenings. Over the time I have used it, it worked very well, I did consider building another to feed one into the other before replenishing the hot tub, but need to look into the pumps capabilities first.
@@royclark8385 thanks Roy, I'm keen to give it a go. What sort of water temperatures were you getting with your setup? Did you have to boost it with grid power?
Great informative UK video Roy which gets straight to the point unlike some US Vloggers.I hope to build this for my lazyspa. Could you send us a link to the piping length and diameter, temp gauge and the timer switch you used. Thank you 😊
Hello Clive. Thanks for viewing. I have listed all the parts in a conversation/reply with Dai. The timer was purchased off ebay, 12V DC Digital 7 Day Programmable Timer Switch LCD Control 16A Power Relay at a cost of around £10
The piping used for the larger of the 2 heaters was pex pipe 15mm bought from wickes on a 50 metre roll, had some left over but could not buy it on a smaller roll at the time. This is the type of temperature guage I used, I wanted one with a long probe so as to protude into the box as much as possible. Grill Thermometer Stainless Steel BBQ Thermometer Cooking Temperature Guage.
@@royclark8385 Hi Roy I built virtually the same setup but slightly bigger box to contain 30 metres of hosepipe. We had a hosepipe ban so thought might as well use the old useless hosepipe. Had some great results during the recent heatwave.My only concern now is, I should replace the hosepipe with PEX pipe painted black or irrigation pipe. I have heard some horror stories, in the past they used heavy metals like cadmium and Lead to make hosepipe and with the heat these chemicals could leach out into the hot tub... What are your views ...🤔👍
@@Clicon61 Hello Clive. To be honest I really don't know, their is a possibility that could happen, I used pex pipe based on its wide usage. If I built again I would again use pex pipe, as its durability is said to be 20+ years. I know chlorinated water is OK in pex pipe but not running through copper pipe.
@@royclark8385 Thanks Roy for your advice, I think I will play on the safe side and get 50m of Pex pipe, 30m for the solar box coils and 20m between the hot tub and solar box. To play on the safe side It might be worth you changing your hose pipe between the solar box and hot tub to Pex pipe, so no toxins/chemicals are leached from the hosepipe by the hot chlorinated returning water 👍😎
Hi Roy Thanks for sharing your design however copper will not react with HCl I presume that it will not also for elemental Cl with all due regards can you verify this. We used copper tubes to cool inside section of glass furnace and flash then for scales by HCl.
Hello, thanks for taking the time to view and comment on my video. My initial information came from a professional swimming pool installer and confirmation of this is found at byjus.com The copper reacts vigorously with the chlorine to form a cloud of copper(II)chloride. When the flask is rinsed with water the copper(II) chloride dissolves forming a blue-green solution. Copper and chlorine do not react rapidly at room temperature, but if the copper is heated, the reaction is vigorous.
Hello Ben I used a 10watt solar panel directly connected to an old 12v car battery. The pump draws a small current but I found the 10w panel keeps the battery topped up fine. The panel can be sourced off ebay very cheap, at only 10w you don't need a charge controller between the battery and solar panel.
Hi Roy I love your video, one of the best I’ve seen so far. Could you list the parts as I’m going to try and replicate your design. I have a similar solar panel set up for our summer house that provides 12v for outside lights. Cheers, Steve in Sussex
What a neat job. well done. Is this only good when sun is out or you can use it in cloudy condition as well? As you know we have more chance of winning a lotto then getting sun on weekends! :) Thanks
Hello. Thanks for viewing my video and taking the time to comment. Sadly it's only effective on sunny days. Here in the UK it works well on warm sunny days but is just a garden ornament on cloudy days.
Hi Roy - Love the video and being 31 x 31 in size it suits my purpose brilliantly. Two questions if I may ? 1 - what size is the upgraded plastic / pex piping is it 10 mm / 13mm or 15mm and do you think the smaller tubing would heat up faster or less as it would create a faster flow as such. Q2 - what flow is the submersible pump please as I have an outside socket right by my lazyspa so I'm thinking of a 240 v one, naturally have to think of the height of the tub and resistance around the piping - Look forward to your reply Cheers Derek N. Wales
Hello Derek. Thanks for taking the time to watch my video. The pipe was bought from screwfix, FPX15B/50 Push-Fit PE-X Barrier Pipe 15mm x 50m White. And the water pump from eBay, 12V Water Pump Submersible Caravan Camper Motorhome High Flow Whale Pump 600L/H Not sure whether using a different diameter pipe would make a notable difference, copper pipe works great but cannot be used with chlorine.
Me again Roy - You have made such a superb compact heater and video you have me on a mission lol - Have thought a lot about it since and I am going to get 25m pex pipe and a 240ac to 12 v dc converter (5amp) and connect that to the timer like yours and that in turn wired up to the whale pump so all will be electrically "safe " as it were. Can I ask please if you have thought of adding insulation inside the box itself as some other videos have it where yours doesn't - do you think it will make a difference in our bizarre UK summer sun as my patio is a sun trap and South facing?
@derek blythin hello Derek. I have added some Insulation (polystyrene) on the rear of my small one, outside on the back, and on a particular warm day it melted it off. So in theory adding Insulation would help and could be worth adding. Although I am not sure how much heat is lost through the box as wood is a fairly good insulator, and the pex pipe would not reach the same temperature as copper pipe.
Great video, 2 quick questions how many of these do you think you would need to get the water up to 32 degrees in summer and also how do you drain out the water for winter. Thanks
Hello. Thanks for your interest. I ran mine in 2020, during the hot summer and my hot tub hit 34 degrees, but it all really depends of the amount of sunshine, less sunshine then a greater volume of water being heated will be more efficient. As for draining during the winter, once you remove the hoses, open the valve, any water will naturally run out, rotating the unit a few times will disperse any trapped water, alternatively blow some air into the top port forcing the water out the bottom.
Hello, thanks for taking the time to view my video and comment. The coil is really to allow a larger volume of water to be heated in a smaller area, you could do lines but I don't believe you would get as much pipe within the box. Also the coiling transfer heat amongst itself, the more air you have passing through the pipe, cools the exterior thus reducing heat build up. You also want water passing slowly through the pipe, the coil compacts 28m into the box.
Hi. It really comes down to surface area, the more pipe you use and surface area covered. Slowing the water flow down did increase the temperature within the pipe, but its a trade off with total volume of water heated through the piping. I made a smaller one using copper pipe and this one is more effective in heating water but running chlorine through copper is said to turn the water green.
The bump is brushless, so in theory it can run dry but it's not advisable. If no water is flowing through the box, it will get very hot inside the box, this could cause damage to the clear perspex, causing it to melt, also the sealant.
Hi I used a 12V Water Pump Submersible Caravan Camper Motorhome High Flow Whale Pump 12 Volt, purchased from eBay, for the large solar heater and a small 12v 10w solar panel operated water pump for the small unit.
Great Video - Glad to find one from the UK that can talk in UK Materials. Rather than US Equivs :)
Hello. Thanks for your comment and taking the time to view my video.
I just made one of these but modified it to 4 ft x 8 ft and was able to get almost 500 ft of tubing in it ( actually 480 feet ). Very heavy so I added two heavy duty wheels. Warning : Do NOT try to stand up after running water through it……. the weight of the water in the tubes is a problem maker. Working on coming up with an Air Hose to plow the lines out before standing up. First day using mine , outside temp was 81. Filled the pool up with 72 degree water. Water came out of my devise at 86. Only getting 6 hrs of Sun so will takes a few days to get pool to 85.
Hi. Well done, that is certainly up scaling..
Hi, this one of the best solutions to heating the hot tub I've seen. Well done. I'm thinking of attempting the same this summer. Could you list the parts please? I like the copper one, might use that in combination with a larger tub tank to have free showers in the outhouse shower cubical. Bit of thought around that one needed? wish me luck! cheers. Dai
Hello. Thanks for viewing. I used 10 metres of 10mm copper piping from my local wickes, around £30. The box was made of some old tongue and groove wood I had in my garage with a simple frame added. I added a piece of polystyrene to the back, on the outside to add insulation but it melted on one day due to the box reaching an internal temperature of 145 degrees.. A sheet of 3 mm perspex was used on the front. I fixed this too the frame via wood screws. You can safely drill perspex using a sharp drill, it won't crack or shatter if you go carefully. Make sure the hole you drill is one size up from the screw being used as if the screw is tight fitting, this will cause a crack upon tightening. The fixings are John guest speed fit for 10mm piping. I added a tap to slow the flow rate down, be careful as if the tap is closed the water inside the box will soon hit boiling point. My water is pumped around the system using a 400L/H Solar Panel Powered Water Pump Garden Pool Pond Fish Aquarium Fountain, bought off ebay. I have a 20ltr water container in black to also absorb heat. The feed pipe is just a short length of common fuel line.
Hope that helps
@@royclark8385 many thanks Roy, I am about to experiment with both your copper piping method for a shower in an outbuilding through a tank and a solar panel powered system for the hot tub....thinking of options around including a battery and controller for a bit more consistent heating,,, ironically just before you replied I purchased a pump and heater in one which I saw on another utuber 's channel.... really excited to see all this working and saving some money... thanks again... Dai
@@royclark8385 could you let me know how that black 20lt container is in the loop system?
@@cosmicdai Hi Dai, the 20ltr black jerry can is solely used with the smaller copper pipe heater, it just happened to be next the the larger one at the time of filming, its not linked in any way to the larger solar heater. Good luck with the build..
Hi, this looks great. Any updates on how it has worked out over the last few months and anything you would change? Thanks
Hello, thanks for taking the time to view and comment on my video. Sadly we have not had the hot tub out in the last 12 months, hopefully this year we will have an opportunity. Although we are soon starting a campervan conversion so it will either be put aside once again or a welcomed break in the evenings. Over the time I have used it, it worked very well, I did consider building another to feed one into the other before replenishing the hot tub, but need to look into the pumps capabilities first.
@@royclark8385 thanks Roy, I'm keen to give it a go. What sort of water temperatures were you getting with your setup? Did you have to boost it with grid power?
Great informative UK video Roy which gets straight to the point unlike some US Vloggers.I hope to build this for my lazyspa.
Could you send us a link to the piping length and diameter, temp gauge and the timer switch you used.
Thank you 😊
Hello Clive. Thanks for viewing. I have listed all the parts in a conversation/reply with Dai. The timer was purchased off ebay, 12V DC Digital 7 Day Programmable Timer Switch LCD Control 16A Power Relay at a cost of around £10
The piping used for the larger of the 2 heaters was pex pipe 15mm bought from wickes on a 50 metre roll, had some left over but could not buy it on a smaller roll at the time. This is the type of temperature guage I used, I wanted one with a long probe so as to protude into the box as much as possible. Grill Thermometer Stainless Steel BBQ Thermometer Cooking Temperature Guage.
@@royclark8385 Hi Roy I built virtually the same setup but slightly bigger box to contain 30 metres of hosepipe. We had a hosepipe ban so thought might as well use the old useless hosepipe.
Had some great results during the recent heatwave.My only concern now is, I should replace the hosepipe with PEX pipe painted black or irrigation pipe.
I have heard some horror stories, in the past they used heavy metals like cadmium and Lead to make hosepipe and with the heat these chemicals could leach out into the hot tub...
What are your views ...🤔👍
@@Clicon61 Hello Clive. To be honest I really don't know, their is a possibility that could happen, I used pex pipe based on its wide usage. If I built again I would again use pex pipe, as its durability is said to be 20+ years.
I know chlorinated water is OK in pex pipe but not running through copper pipe.
@@royclark8385 Thanks Roy for your advice, I think I will play on the safe side and get 50m of Pex pipe, 30m for the solar box coils and 20m between the hot tub and solar box. To play on the safe side It might be worth you changing your hose pipe between the solar box and hot tub to Pex pipe, so no toxins/chemicals are leached from the hosepipe by the hot chlorinated returning water 👍😎
Hi Roy Thanks for sharing your design however copper will not react with HCl I presume that it will not also for elemental Cl with all due regards can you verify this. We used copper tubes to cool inside section of glass furnace and flash then for scales by HCl.
Hello, thanks for taking the time to view and comment on my video. My initial information came from a professional swimming pool installer and confirmation of this is found at
byjus.com
The copper reacts vigorously with the chlorine to form a cloud of copper(II)chloride. When the flask is rinsed with water the copper(II) chloride dissolves forming a blue-green solution. Copper and chlorine do not react rapidly at room temperature, but if the copper is heated, the reaction is vigorous.
Hi brilliant video is the pex 10mm or 15mm thickness?
Hello. Thanks for viewing my video and taking the time to comment. I believe it was 5mm or 6mm.
Hi Roy, great video thanks you. Can I ask how you recharge the 12v battery used with the whale pump and timer?
Regards
Ben
Hello Ben
I used a 10watt solar panel directly connected to an old 12v car battery. The pump draws a small current but I found the 10w panel keeps the battery topped up fine. The panel can be sourced off ebay very cheap, at only 10w you don't need a charge controller between the battery and solar panel.
Hi Roy I love your video, one of the best I’ve seen so far. Could you list the parts as I’m going to try and replicate your design. I have a similar solar panel set up for our summer house that provides 12v for outside lights. Cheers, Steve in Sussex
Hello Steve. Thanks for viewing, I have listed all parts used in my replies to previous comments.
Their is also some additional tips I discovered whilst building which may be of some use.
What a neat job. well done. Is this only good when sun is out or you can use it in cloudy condition as well? As you know we have more chance of winning a lotto then getting sun on weekends! :)
Thanks
Hello. Thanks for viewing my video and taking the time to comment. Sadly it's only effective on sunny days. Here in the UK it works well on warm sunny days but is just a garden ornament on cloudy days.
Hi Roy - Love the video and being 31 x 31 in size it suits my purpose brilliantly. Two questions if I may ? 1 - what size is the upgraded plastic / pex piping is it 10 mm / 13mm or 15mm and do you think the smaller tubing would heat up faster or less as it would create a faster flow as such. Q2 - what flow is the submersible pump please as I have an outside socket right by my lazyspa so I'm thinking of a 240 v one, naturally have to think of the height of the tub and resistance around the piping - Look forward to your reply Cheers Derek N. Wales
Hello Derek. Thanks for taking the time to watch my video. The pipe was bought from screwfix,
FPX15B/50 Push-Fit PE-X Barrier Pipe 15mm x 50m White. And the water pump from eBay,
12V Water Pump Submersible Caravan Camper Motorhome High Flow Whale Pump 600L/H
Not sure whether using a different diameter pipe would make a notable difference, copper pipe works great but cannot be used with chlorine.
Me again Roy - You have made such a superb compact heater and video you have me on a mission lol - Have thought a lot about it since and I am going to get 25m pex pipe and a 240ac to 12 v dc converter (5amp) and connect that to the timer like yours and that in turn wired up to the whale pump so all will be electrically "safe " as it were. Can I ask please if you have thought of adding insulation inside the box itself as some other videos have it where yours doesn't - do you think it will make a difference in our bizarre UK summer sun as my patio is a sun trap and South facing?
@derek blythin hello Derek. I have added some Insulation (polystyrene) on the rear of my small one, outside on the back, and on a particular warm day it melted it off. So in theory adding Insulation would help and could be worth adding. Although I am not sure how much heat is lost through the box as wood is a fairly good insulator, and the pex pipe would not reach the same temperature as copper pipe.
Great video, 2 quick questions how many of these do you think you would need to get the water up to 32 degrees in summer and also how do you drain out the water for winter. Thanks
Hello. Thanks for your interest. I ran mine in 2020, during the hot summer and my hot tub hit 34 degrees, but it all really depends of the amount of sunshine, less sunshine then a greater volume of water being heated will be more efficient. As for draining during the winter, once you remove the hoses, open the valve, any water will naturally run out, rotating the unit a few times will disperse any trapped water, alternatively blow some air into the top port forcing the water out the bottom.
Sorry I meant greater volume of water would be less efficient..
Is the tubing coil really necessary? What would happen if you just pumped the water in the top and let it drain back into the pool?
Hello, thanks for taking the time to view my video and comment. The coil is really to allow a larger volume of water to be heated in a smaller area, you could do lines but I don't believe you would get as much pipe within the box. Also the coiling transfer heat amongst itself, the more air you have passing through the pipe, cools the exterior thus reducing heat build up.
You also want water passing slowly through the pipe, the coil compacts 28m into the box.
Is it worth adding a small Solar panel to the top of the battery box to keep the battery topped up?
Hello. I do have a 10watt panel charging my 12v battery. Being 10watt or less means you don't need a charge controller from the panel to the battery.
Do you think if you scaled it up maybe on a shed roof, so it has more time to heat up it would work better?
Hi. It really comes down to surface area, the more pipe you use and surface area covered. Slowing the water flow down did increase the temperature within the pipe, but its a trade off with total volume of water heated through the piping. I made a smaller one using copper pipe and this one is more effective in heating water but running chlorine through copper is said to turn the water green.
Also fixing it to a shed roof will limit the ability to angle it towards the sun throughout the day.
What happens if it runs dry? Will that damage it?
The bump is brushless, so in theory it can run dry but it's not advisable. If no water is flowing through the box, it will get very hot inside the box, this could cause damage to the clear perspex, causing it to melt, also the sealant.
@@royclark8385 thanks 👍
Hi what pump did you use?
Hi I used a 12V Water Pump Submersible Caravan Camper Motorhome High Flow Whale Pump 12 Volt, purchased from eBay, for the large solar heater and a small 12v 10w solar panel operated water pump for the small unit.