Nice video. I have been using this system for at least 15 years now. But I have 3 boxes each 2 by 6 feet that help heat my cabin in the winter time here in Alaska as long as of course we have sun light which can be a challenge. But the 4 months during spring - summer the boxes give us all the hot water we can use. I ran my copper tubing left to right and of course much larger dia. At 1/2" dia. Plus my boxes are 6 inches deep to cap all the heat possible. I am always playing around with stuff like this living off the grid. I also have 3 wind mills that are always spinning - near the ocean at least 15 - 35 mph winds to keep my batteries charged along with solar so we live a very comfortable life style free once I pay for materials. Thank You
Instead of using a glass front, have you thought about using double-walled lexan sheeting? This would insulate against heat radiation overnight and trap more heat in daytime. It's not as if the thing needs to be optically clear.... How do you capture for winter heat? Is that an air-based heatbox or do you heat water and use a radiator? if the former, do you have a mesh installed?
Lexan would melt and stretch under this kind of use. To give you some idea we have had cars left with their windows closed in Florida in which the steering wheels actually melted and drooped. And our cars are not even designed to be heat traps.
I had an uncle who built a system larger than yours (same idea) and mounted it on top of his garage. He ran the tube of heated water into his pool - he had 90+ degrees of in his pool in winter! Good job.
T C , What part of the U.S. did your uncle live? (Assuming he lived in the U.S.) I'm trying to get ideas for my pool where I live in East Tennessee at about 1,000 feet above sea level. Do you recall how big his system was? Tks!
@@MeAncient He lived in Fresno, CA.I don't know the elevation there, but I don't think it matters that much. It's about using the sun & capturing as much of the reflection as possible.
did the same thing in '73 with four truck radiators connected with hoses and mounted on a flat panel painted black and glazed with used windows. It was cheap and provided free hot outdoor showers.
Good idea, but paint the copper tubing flat black, have it raised up and put a reflective layer below. They do have a new paint out called Vantablack that absorbs around 99% of light which should help.
I was impressed by the video; well made, well explained with good DIY instructions. I read all the comments and a lot were sold on the idea of a reflector but the way I see it a certain amount of sunlight would be reflected back out of the glass front. Instead, a metal back-plate of aluminium flashing also painted black would get hooter than the plywood backing. This would increase the internal air-temperature and heat more water. My only other point is that because of the spiral design the water would not passively flow as it would if the pipes were vertically oriented. I realize this would call for soldered joints and a lot more expertise and labor and would add to the possibility of leaks. I wonder what would be the minimum radius that copper tubing could be bent into using a bending kit. I used to at one time bend brake pipes using a kit like this. I assume they are available in various sizes. Any thoughts?
This is by far one of the easiest hot water panel builds I have seen. My questions are 1. How big is your storage tank? Must have to be large as the volume isn't that much. I would think that using 1/2" copper tubing would drop the water temp a little, which would be ok, and dramatically increase your volume ability. It also appears, that as hot as the water is coming out, a person could use this panel or a series of panels for a radiant heat system in the home or shop. Your thoughts.
I LOVE LOVE LOVE your format of showing a quick snippet of the conclusion up front and then slow down to show the build. Perfect! May want to read an old book called "Direct Use of the Sun's Energy" by Farrington (1964) Very cool stuff. He shows a good idea where one would have the coils or tubing sitting atop a large metal plate that conducts and radiates heat. Brilliant.
Thank you for an informative, easy to follow tutorial on how to simply heat water. I really don't know where I would be if it wasn't for the few people like you who generously share stuff like this. This will be passed on to my nephew and my younger son who are helping me build my off grid cabin. I believe that stuff like this should be preserved for future generations (who knows when Sunspot activity will leave us back in the dark ages and knowledge such as yours could mean the difference between cutting tons of wood to get hot water or having a setup like yours which is always keeping the water warm if not hot. I am subscribing to see what else you have and when (this awful gale force winds thing has been going on for three years now, despite this we are making headway and have a road laid in so ww don't have to hike through the forest lol. I promise to put up a video and to pass on anything I learn during my build.
I haven't read all of the comments, and what not but I thought that I would throw in the fact that I have used a 50 roll of 1/2" black water line just laying out in the sun for a couple of hours to produce 117 degrees. I always wanted to go further with it, but never have been able to get back to it. I ultimately used that roll of water line to make a cold water machine out of an old obsolete Coke machine though. I just gutted all of the unnecessary stuff inside and kept the cooling part of it and put the roll of pipe inside with a line coming in and going out. That was some COOOLD water coming out and was very useful at work during the summer heat.
I built such a SWH device like this in 1991, but used a Pex Pipe in Black from Isral with 100 meter x 16mm in a M2 box sealed with K glass, worked fantastic when i tested it while in Cyprus from 1994 to 1998
Thank You! I was thinking about the pvc one but I don't like storing the water in the plastic especially when it gets hot. Just don't trust it not to leech into the water. Copper is perfect!!
I recently made a heater from black plastic pipe here in Thailand, as they only use cold water for washing dishes. Something you need to be very mindful of, is the pressure build up if both end are sealed. I left my inlet to the sink open to avoid any pressure problems.
Nice and simple design, but zip ties will crack in the heat over time. Recommend using copper wire instead. I really like the amount of detail in your videos. Other DIY vid makers could learn a thing or 2 from you. Great job!
nuckelhed7 - Also prolonged exposure to UV light destroys plastic zip ties. Here in the south of Spain they last about a month in summer and just fall to bits!
About 35 years ago i saw an article in Organic Gardening magazine where a man built a large flat box on his roof and instead of copper tubing he used garden hose. He enclosed it with glass and of course painted the inside of box and tbe hose with black paint. He hooked up the hose to his hot water heater and most days it never turned on and on cloudy days it did so it was a good back-up. His was not as compact as yours, but he had a whole family to heat water for. It was meant to be a permanently in place installation.
I just coil 3 100ft Garden hoses on my sun room roof It is tied into my hot water side of my house . It gets hot enough that we add cold water for showers
Hi , your comment interests me . Hot water wants to rise , and I presume your tank is down . How are you circulating the water that is heated on the roof . I built a hot air collector for winter heating and it works Good , now I'm exploring heating water for summer months , hope to hear from you , Thanks .
Just paint your tube in black and the energy harvesting efficiency of your heater will double. (In fact probably more than double). Edit : I saw the end or jour video, the icon you put is a bit misleading. Nice project ! You can also strongly increase the efficency by adding some 45+° mirror on each side of your frame. Estimated gain with 4 mirrors, about 3 times more heat harvested than with only the tube.
Hi Patazertyul...not understanding the mirror addition, how does adding the 4 strips of affect the heat. Surely the mirror reflects the energy back, or do you put the mirrors in back to front.? Southampton UK
Thanks for these two great demonstration & instruction videos comparing poly pipe with copper tube. Now we really have the answers we need for cheap hot water 😀
Very nice design especially like the use of off the shelf products less cutting less fuss, standard coil, standard fittings nothing overly complex nicely done that man just wish I had your sun to run it.....
My grandparents bought a home in Coral Gables, FL just after WWII It was built with a 15 gallon water heater/ tank with a small 3'x3' solar collector panel. It would give grand dad his after work shower and grandmother water for washing the dishes after dinner. She took her shower in the middle of the day to replenish the tank as she didn't use hot water until dinner. But it worked for half of the Gables back then.
I have accomplished a number of solar projects and would like to pass along a couple of comments. First, plastic tie wraps will get brittle in the sun, I would have used copper wire to attache the tubing by stitching it through the holes in a continuous length. Also, I would have made the backing plate out of metal painting it flat black before attaching the tubing to absorb a little extra energy ! GOOD PROJECT THOUGH !
Good ideas. I would add that one should consider up-sizing from 50 feet of copper tubing to 100 feet. This would give increased output capacity. Of course one might also make two or three of these and simply connect them to get the same effect. I'm thinking of having a larger/longer sustained output.
I had the same idea to use a roll of coiled copper tubing like that. Only in my design, the coil is elevated about an inch over a reflective glass mirror and the coil windings are separated by about an inch. This way the copper gets cooked from both sides. So you need less copper to do the same job. A tempered glass cover is optional.
Usually, a long tube is placed in a parabolic container so that the focus of the parabola hits the tube. That way you need very little copper. However, building a trench shaped parabolic system is a bit of a fuss. You can get a piece of very large PVC pipe and cut it in half length wise, and line the halves with reflective mirror material so that the two halves focus on the pipe is a sloppy sort of way and get a decent unit that is a bit less efficient than a parabolic unit. Or you can get a Fresnel lens from some old TV sets and focus it on a coil. Use caution as the heat in some well built units is enough to set the boxes on fire. You will also find that your typical hot water heater will rapidly fail with very hot water inside it. They are not built for that heat level. A 180 degree hot water heater should be available as some businesses are required to use them for dish washing and the like.
In order for a fresnel lens to be of any use is if it is bigger than the collector, however, simple mirrors do the same thing and are much easier to aim. As the sun moves across the sky, the fresnel lens would have to be moved to change the focal point. Mirrors are easier to track. Nevertheless, the biggest obstacle is not how to heat it better, but how to keep it from overheating.
It's also really hard to create good cheap mirrors, especially on a curved surface, and at some point, you might as well just go buy something instead of pissing around trying to make an inevitably shittier version. The flat mirror idea is dumb, however, as you'd lose a lot of light going straight out the glass you're bounding it back at. You wouldn't get twice the value out anyways, since the copper already absorbed some of light on the first pass. In fact, the better the copper is at absorbing the energy, the less use you'll get out of a second pass because the less light will be left. All of which is irrelevant, because flat black is already extremely good at converting light into heat, meaning very little is wasted by lack of absorption in the first place.
The glass cover may be required in some climates. Some commercial units have tubing that is inside glass tubing with a vacuum between the glass and copper. Imagine air at 10 below zero passing over the copper you are trying to heat. That type of unit can produce hot water in areas with very cold winters. In hot climates i advise people to use caution as the temperature inside a glass covered unit comes very close to the ignition temperature of wood. A piece of wood with a 90 degree edge on it just might ignite. I am not aware of a situation in which such a fire has taken place but it is something to consider. Obviously any system that uses a lens can cause fires if the focus of the lens moves due to wind or whatever.
I fail to see why you think the flat mirror idea is dumb. The solar radiant heat from the sun first strikes the top of the copper directly, then the radiant heat that passed in between the copper tubes strikes the mirror and bounces back into the bottom of the copper tubes. Not all of the reflected heat will strike the copper tubes, but some will, which means its more efficient. Flat mirrors are cheap and plentiful.
I used black PTFE pipe woven back and forth across the south end of my house. a copper heat transfer inside my water tank + a small central heating pump, header tank and antifreeze. works ok in winter too. enough heat for a bath, add electric heater for ten minutes & your heading for steamy bath.
Here is what needs to be built a circuit that kicks on the pump or valve at 165 placing the water into an insulated vessel. You could store the water on site. You would need another pump to give it that closed loop heating so the water in the vessel would take the cold off the bottom and add it to the solar and the heat from that would go into the vessel to the top.
Nice water heater for my pool. Do you know at what speed/rate is the water going into the coil to get those temperatures out of it? Why much time does the water need to spend inside the coil to get really hot out of it? I am trying to build my system with 1/2" copper tubing and would consider replacing the tubing with 1/4" coil, as you suggest to get hotter water "faster" due to the smaller diameter tubing.
I really like this design and it looks simple enough for people to build. Do you put wooden stops on top of the glass to keep it from falling out or does the sealant for weather proofing keep the glass in place?Thank you for such an easy to follow video.
Great idea. The only thing I would have done differently would be putting a thin black like slate board like a chalkboard or guage 3-6 sheet metal (blackened) where the glass would have been.
This is a great project! Simple, efficient, and inexpensive. One suggestion have you thought about using tile as the backing to gain additonal heat retention. Also tie straps won't last in the heat, small c-clamps secured with screws would last longer. Again great projector. Great thought starter.
This is awesome. I'm building it this weekend to use as a pool heater this summer. Can you please tell me how thick the 20x20 wood is that you zip tie the copper pipe to? Also what are the lengths of the square dowels and what is the thickness of the glass? Thanks!
Nice and simple design. But I would put metal sheet under the pipe - that would increase absorbing surface. Next step - to weld pipe to the backsheet, but that would increase labor.
Good video, pretty simple with very little extras. I like that you didn’t try giving us your life story and talk my head off versus just getting to the point. However, I had a hard time getting past that harbor freight drill you are using. Please invest in a nice brushless cordless drill and throw that garbage away. Thanks.
i'm glad you liked the video! i don't have the harbor freight drill anymore. it didn't have enough power for the tougher tasks. at the moment i'm just using corded drills.
I would add 2 more upgrades: (1) coil background made of metal, insulated to give the heat only towards the coil, (2) mirrors to reflect the additional sun light towards the coil
In Manitoba Canada we use black aqua line ABS tubing any ware in dia. from 3/4 inch to 1 1/4 inch with a small circ pump. i have generally put the coil on the house or garage roof or build a trellis type fence southern exposure is best. no need to enclose the ABS tubing. 65 to 70F water inlet temp produces hot water any ware from 105 to 125F. Below freezing temps system is drained and shut down
Great job... I am always amazed at the comments on how to do it better by people that most likely have never done anything like it at all... Great little heater....
Nicely done, but what temperature is your water going in? You have a 30 in x 30 in box, which is about 0.76 m x 0.76 m. So you're getting about 0.57 square metres of solar access (in fact less, because not all your area is pipe.) The very most you can get from sunlight is about 1 kW per square metre. So your box could get a maximum of 570 watts, if you captured the full area of 0.57 m^2. Let's say you're getting 500 W and 100% efficiency to the water (which itself is a big call as you're not getting 100% efficiency.) Energy required to heat water: E = m. c (delta T). m. is the mass flow rate. 1 gallon every 3 minutes is 0.021 kg per second. c is the specific heat of water (4.186 kJ per kg.K, where K is 1 kelvin, or 1 degree C). delta T is the change in temperature. So with 500 watts at that flow rate: delta T = (0.5 kW)/(m. c) = 0.5 / (0.021 * 4.186) = 5.6 degrees C. But you're getting an output temperature of 75 degrees C. So one of the following is true: > your water is going in at close to 70 degrees C > your flow rate much lower than your estimate > I completely wrong in my calculations (Whichever it is, that's a great result and a nice low-cost design.) I would have thought you could achieve a 30 degree C temperature increase with about 1/2 kg water every 3 minutes. Which is about about an eighth of a gallon.
We do something similar on our farm. In winter at between midday and 2pm, the water is warm enough to wash the dishes with.. In summer it is scolding hot for most of the day. We use black plastic pipe, not sprayed copper.
this is one way to go about it for sure I like the idea for sure. I think if I was going to build one I would build it in a metal box with insulation. to add to the durability and might make it a little more efficient. good job
Should have a metal sheet backing (like aluminum) behind the copper coils to transfer more heat to the coils. Wood backing a heat insulator. This way you can spread out he coil rings a little wider for a larger thermo heat system. Buy dense black paint as used for camo spray paint to increase transfer of heat.
Very nice work. One comment: I predict that, over a fairly short time of use, the zip tries will break down and crumble. Wire would be better, with a layer of IR reflective insulation behind the mounting panel would last longer and perform better.
+LFOD Using plastic to secure the tubing is better. The problem with the zip ties is they will become brittle and be prone to breaking easily. If you use ferrous metal strapping instead of copper, you run into the danger of electrolysis occurring. Try using copper wire instead. 10 or 12 gauge wire will work just fine.
Electrolysis can only happen if the water is in contact with BOTH materials. In this case the water only comes into contact with the copper, the wire (or whatever you use) is only touching the outside of the copper pipe, so it does not come in contact with the water.
Nice project. Bottom of the heater should be from metal like aluminium or better copper.If choose copper should painted black for absorb and radiate back more heat. If choose aluminium make it shining like a mirror.You gate more heat .Or get some aluminium foil and wrap all plywood in aluminium foil.
If you get some aluminum chips from a lathe operation, get the oil off , and paint them black you can increase the active surface many times over and get much hotter water easily. I think you would be shocked at the heat gain.
"you can increase the active surface area many times over"?? Um.. no you can't. There is only so much light per area. Any minor additional reflection that you'd get from painted metal chips would be quite negligible.
+Justin Bozeman Unless you get insulation for free or you have some laying around gathering dust, insulation won't be of much use either. Glass or plexiglass won't hold the heat in for long & the thermal mass of rocks/pebbles isn't very high (which means you wouldn't get enough extra heat from them to make it worth your while for such a small volume of space & for such a small thermal difference between your inside temp & the max temp the rocks will reach.
Thinking about putting copper tubing coil in a water tank. The hot water will circulate through the copper coil heating the water. When the water gets hot the circulation will stop until it cools or you use some hot water putting cold water in. The water will be heated using coraplast with water running through it from a pipe on one end out of a pipe on the other end.
great ideal. use a lot of on the roof. thing is, you probably get great hot water by noon when the sun is apex for a shower. the rest of the time warm water is good for dish washing and such
Just curious on how you would control the temperature, remember that we usually set up the heaters around 120 F to avoid scalding, I found this same set up in older building roofs for the same purpose but they compliment them with mixing and control valves.
Thank you for sharing your experience, it's golden. However, I'm wondering could you get better result with no space between copper circles. In summer it could not be matter. But, in fall or winter air around copper can make them less warm. If no space between them, they can share own heat with inner or outer circle too? Also wondering, if bigger copper tubes could get more heat via more copper surface = more heat? Thank you for your time, Mehmet
The idea is that you do not want the sunlight reflected back out to the air....you want the light to be absorbed and converted into heat. I wonder if just using black painted plywood would be as good as painted aluminum.?
I like my idea of a black tank of water with either air pressurized or gravity fed...but it does need bleach cleaning (or added) now and then. Nice video demo👍
This is awesome I instantly started thinking how I could take advantage of something like this and my first idea was to use this to pre heat the water in to an electrical water heater on a hot day the thing would barely need to work at all
es muy interesante la forma en que has resuelto el problema de las soldaduras con estaño pero¿cuanto metros de caño has usado en este proyecto me gustaria saberlo..saludos de un amante de la energia renovable.
Makes sense doesn't it! My father had a swimming pool built and had the return water pipe buried underground. I asked him why he didn't have it go up and over the pool house in coils so the sun could heat it up. The look on his face!
I just did something similar as well. I left my black hose in the grass for a day. Its about 300 ft worth of hose. When I spray that puppy boy I got me some hot ass water!
So a couple ideas I was thinking of. Im going to make one of these and put on my roof of the garage which is right above my pool but 1- if i cover the back piece of plywood with aluminum foil and then also attach multiple magnifying glasses on the inside of the plexiglass before sealing it....would I get more heat? 2- do you recommend copper tubing or pex?? Which will get more heat?
hi there. copper really is the better choice. black tube usually only handles up to 180F. plus copper lasts way longer - 50 plus years verses maybe 3 to 5.
@Howard Stymiest The best thermal performance approach is a copper sheet bonded (soldered) to copper tubing. The tubing runs in a back-and-forth pattern, reducing the distance the heat has to travel in the copper absorber sheet. Then apply a black, high-absorption coating. Paint is not the best coating, however it is low-cost. A 'solar' paint would be best.
Plastic degrades in sunlight. Adding carbon black (hence the black color) helps a lot, but it will still become brittle over time and crack or blow out at some point.
The desired properties are high thermal conductivity and corrosion resistance. Aluminum is an option (excellent thermal conductivity) and steel would work (not as well). However, any time you mix dissimilar metals (copper with aluminum or steel) you're going to have corrosion issues - look up "bimetallic corrosion" or "bimetallic corrosion table".
I am considering building a few of these for my pool, it's 30,000 gallons, so I figure maybe 12 or so. I'll have to do some figuring for pipe and pump size, run a single pipe up the roof, maybe 1"to, 1 1/2" pipe to feed the banks from a home made copper manifold, Then back down the roof in a larger size pipe and manifold. We used 1 1/2" up and 2" down, back when I installed solar pool heaters for a company here in California. I need a cheaper alternative, like this.
Is it absolutely necessary to use copper or would black rubber pipe do the same at a lower cost ? Also question = waterproof box and fill with antifreeze or use a 2nd larger diameter pipe and fill the void with antifreeze??
If you want an easy demo simply coil a garden hose on the pool deck and you may be shocked at how hot the water gets flowing through the hose. Simply keep the flow rate low and you could even use the pools filter pump to send a trickle through that hose whenever it is turned on.
Hi there i have just found out about a thermal heater and honestly know nothing about them, im wondering is it a continuous flow of hot water all the while the hose is running or is this limited please? Any advice would be great, also how exactly it works, i imagine solar power, does the solar energy store in the pipes? I honestly have no idea :s Definatelyintersted in making one if it could fit the means i have in mind for it Thanks
How many gallons does it put out before it goes cold? Does this work in 32° weather? Will this fill up a bathtub? What about fire hazard? Does it get so hot (in the summer) ,would it catch on fire? Love to make one.
Zip ties wont last you, use stripped bread ties or metal wire. Also paint the base of the copper coil black. If water hot water needed at night placing the coil atop a rocket mass heater will do the job for which I would suggest a tube-shaped coil inside a coffee of paint can insulated. I like that you used glass but I'd recommend maybe tempered plexi glass.
You could use all that copper tubing to circulate hot water through it and have a fan move air through it to heat the air in a green house or home. Super easy!
This is a good idea as a collector, but You need to store the water and keep it hot so the water need to be circulating inside of a water tank. This is just part of the job , but maybe I am am misunderstanding.
Do not try it with a home hot water heater. They can not handle the degree of heat that collectors can produce and will rapidly fail. You will need the 180 degree water heaters required in restaurants. It would be better to make your own storage system but it would be quite a project and require skills most people don't have. If you can find a stainless steel tank with a large enough capacity it is a good start and then add a shut off when the water gets too hot. You can actually produce boiling water in some collectors.
any water heater will do the same job. the only constraints are the capacity (GAL) and the pop off relief valve ,remember warter boils at 212 and a hotwater heater then becomes a boiler and steam pressure is alot higher can be very dangerouse at that point.
That is not correct. There is a huge difference in the materials that coat an industrial water heater that must reach 180F and the water heaters that you buy for your home. The coating on the inside of a home hot water heater will decompose quite quickly when exposed to water at 180F. You can see the difference in the prices charged. Get a quote on a 180F heater at 40 gallons and then get quotes on home water heaters of the same capacity.
have you considered heating it with a Fresnel TV lens? off focus so you don't melt the unit. auto tracking the sun is a relatively simple circuit I've seen a couple vids. I am curious, always have been, does painting them black increase heat absorption significantly?
New Doctrine Equals Heresy An Aluminium sheet bent into a parabola and focused onto a 5 cm diameter copper tube will produce boiling water, and the reflector can be made to turn slowly round the axis of the tube to keep in focus. The tube could be filled with oil and pumped through a heat exchanger - or you could run a steam engine off it!
Cottage Gypsies Copper melts at 1080 C, so it would be safe even if the water flow ceased, and would be more likely to melt the brazing alloys or solder first. Or set fire to the casing. For most purposes , flat-plate collectors are enough for domestic hot water, though a pumped system with a longish copper pipe and curved aluminium parabolic reflector would give improved results in high latitudes.A sheet of aluminium 2.4metres long, curved with supporting profiled braces, and a 2.4metre 50mm diameter copper pipe at the focus would potentially give higher temperatures. See "sgirrel" UA-cam clip for an example. There are many possibilities, depending on needs, and the parabolic reflector could give you water hot enough to drive a steam engine, pumping oil through the copper pipe instead of water, and using a heat-exchanger.
wow, your smart....i didn't even understand most that answer,,,i appreciate you taking time to explain it tho..but i do know now, copper has to be very very hot to melt...lol.....thank you, have a great day..
what about evacuating inside so interior was in a vacuum ?was watching vids on evacuated glass tubes and thought it would be easier to do a box.what do y'all think?
How about 2 fold out doors like a dart cabinet with mirrors on the inside to reflect more light in? Perhaps with adjustable arms or chains to hold in place. Just a thought.
I'm doing something similar, only with about 160' of 1/2" poly tubing. I'd like to use 1/2" copper tubing but that's all too spendy. Yours does look good, well done.
+McGaughey that's a good idea! Could a plumb a load together all tightly, paint the sun side black with a sheet of glass over the top? would look tidy aswell
I have an idea that i have not seen anyone try yet. There are numerous videos on U Tube about solar hot air collectors. They are cheap and easy to build and the temperature inside those collector boxes get quite high. A small copper coil could be combined within those collectors to heat water. One advantage would be protection against freezing as even at 20F these hot air collectors get above 120 F easily. If the air around the copper coil is 120 F or more you can bet that the water inside that coil will be close to the same temperature. Besides being far less expensive to build the units would also be lighter in weight. Simply view a hot air solar heater or two on U Tube and think of a copper coil at the top of the box.
Great Would you try to use a Fresnel Lens but to calibrate it in a way that the sunlight rays focused on the Copper coils only and Let's See how much the water temperature can be increased ?? 10x great video.
I remember this guy who had a. Giant(4' across 18" deep ) bird bath looking thing next his pool that had a huge copper spool in it. And his pool pump was hooked up to it and his pool was a jacuzzi it would stay 100° like it was nothinhg ..... His uncle was a contractor who put the pool in and didnt want to pay to heat the pool ...he lived next to phoenix college ....
I have a 30’ round above ground pool in maine. I wonder how many of these I would need to extend the season. My husband built a larger one with black plastic and similar design but only get 90 degrees F ?????
How long will it heat the water while in the sun? Does it get cold at some point when the flow is on all the time. You need a storage tank and a circulator pump.
Hi and I am making the solar water heater as a "closed loop" for my hot tub. I am curious what or where I can find the suitable pump (preferably off the solar panels or battery) that will drive the water through the heater. Any ideas on what to do next AND also what did you use as the glass part? is it tampered or polycarbonate and thickness. Thanks for the information and hope to hear from you soon as possible.
I am thinking of doing the same thing with my hot tub. Electric bill is killing me. Looking to do somthing like this to preheat the water. Want to share notes. ?
Sure! Only thing I am doing is using the sun to keep the hot tub from running on constant basis and as well as heating it up. I'd appreciate any advice or information on this. I am looking for a solar power capable water pump but don't want a HUGE one as the water needs to heat up before it comes out. Thanks
this is awesome, I think it could be slightly improved if you used some reclaimed sheet metal to attach the copper tubing to as well as to hold the heat for longer durations. thanks for the tutorial!!
What's the volume versus the flow? or is it contentions heated to 150 degrees all day long if it is a flowing. Or, are we talking about a gallon of hot water heated up one at a time? AND if so what's the time to heat to 150 degrees per gallon. , Just a wondering if you could take a long shower or is the flw to slow.
Nice video. I have been using this system for at least 15 years now. But I have 3 boxes each 2 by 6 feet that help heat my cabin in the winter time here in Alaska as long as of course we have sun light which can be a challenge. But the 4 months during spring - summer the boxes give us all the hot water we can use. I ran my copper tubing left to right and of course much larger dia. At 1/2" dia. Plus my boxes are 6 inches deep to cap all the heat possible. I am always playing around with stuff like this living off the grid. I also have 3 wind mills that are always spinning - near the ocean at least 15 - 35 mph winds to keep my batteries charged along with solar so we live a very comfortable life style free once I pay for materials. Thank You
Sounds great!
K-9 COOPER
You are lucky that far north. You can get free heat and also free cold. Just leave the fridge out on the porch and don't bother to plug it in.
Instead of using a glass front, have you thought about using double-walled lexan sheeting? This would insulate against heat radiation overnight and trap more heat in daytime. It's not as if the thing needs to be optically clear....
How do you capture for winter heat? Is that an air-based heatbox or do you heat water and use a radiator? if the former, do you have a mesh installed?
Lexan would melt and stretch under this kind of use. To give you some idea we have had cars left with their windows closed in Florida in which the steering wheels actually melted and drooped. And our cars are not even designed to be heat traps.
I had an uncle who built a system larger than yours (same idea) and mounted it on top of his garage. He ran the tube of heated water into his pool - he had 90+ degrees of in his pool in winter! Good job.
T C , What part of the U.S. did your uncle live? (Assuming he lived in the U.S.) I'm trying to get ideas for my pool where I live in East Tennessee at about 1,000 feet above sea level. Do you recall how big his system was? Tks!
@@MeAncient He lived in Fresno, CA.I don't know the elevation there, but I don't think it matters that much. It's about using the sun & capturing as much of the reflection as possible.
@@TC-er5xy Tks!!
@@MeAncient you will need a pool cover to keep the water hot or you will loose all your heat... It's too cold in Tennessee not to use a cover
did the same thing in '73 with four truck radiators connected with hoses and mounted on a flat panel painted black and glazed with used windows. It was cheap and provided free hot
outdoor showers.
How old are u now
Good idea, but paint the copper tubing flat black, have it raised up and put a reflective layer below. They do have a new paint out called Vantablack that absorbs around 99% of light which should help.
I was impressed by the video; well made, well explained with good DIY instructions. I read all the comments and a lot were sold on the idea of a reflector but the way I see it a certain amount of sunlight would be reflected back out of the glass front. Instead, a metal back-plate of aluminium flashing also painted black would get hooter than the plywood backing. This would increase the internal air-temperature and heat more water.
My only other point is that because of the spiral design the water would not passively flow as it would if the pipes were vertically oriented. I realize this would call for soldered joints and a lot more expertise and labor and would add to the possibility of leaks. I wonder what would be the minimum radius that copper tubing could be bent into using a bending kit. I used to at one time bend brake pipes using a kit like this. I assume they are available in various sizes. Any thoughts?
This is by far one of the easiest hot water panel builds I have seen. My questions are 1. How big is your storage tank? Must have to be large as the volume isn't that much. I would think that using 1/2" copper tubing would drop the water temp a little, which would be ok, and dramatically increase your volume ability. It also appears, that as hot as the water is coming out, a person could use this panel or a series of panels for a radiant heat system in the home or shop. Your thoughts.
I LOVE LOVE LOVE your format of showing a quick snippet of the conclusion up front and then slow down to show the build. Perfect!
May want to read an old book called "Direct Use of the Sun's Energy" by Farrington (1964) Very cool stuff. He shows a good idea where one would have the coils or tubing sitting atop a large metal plate that conducts and radiates heat. Brilliant.
What a brilliant, compact, portable, and economical way of storing the Suns thermal energy! Your video is very inspiring, well done!
Thank you very much!
Thank you for an informative, easy to follow tutorial on how to simply heat water. I really don't know where I would be if it wasn't for the few people like you who generously share stuff like this. This will be passed on to my nephew and my younger son who are helping me build my off grid cabin. I believe that stuff like this should be preserved for future generations (who knows when Sunspot activity will leave us back in the dark ages and knowledge such as yours could mean the difference between cutting tons of wood to get hot water or having a setup like yours which is always keeping the water warm if not hot. I am subscribing to see what else you have and when (this awful gale force winds thing has been going on for three years now, despite this we are making headway and have a road laid in so ww don't have to hike through the forest lol. I promise to put up a video and to pass on anything I learn during my build.
We usually use Heat Pipe collector with Evacuated Tube to heat water. Then we integrated with Pressured Tank.
I haven't read all of the comments, and what not but I thought that I would throw in the fact that I have used a 50 roll of 1/2" black water line just laying out in the sun for a couple of hours to produce 117 degrees. I always wanted to go further with it, but never have been able to get back to it. I ultimately used that roll of water line to make a cold water machine out of an old obsolete Coke machine though. I just gutted all of the unnecessary stuff inside and kept the cooling part of it and put the roll of pipe inside with a line coming in and going out. That was some COOOLD water coming out and was very useful at work during the summer heat.
I built such a SWH device like this in 1991, but used a Pex Pipe in Black from Isral with 100 meter x 16mm in a M2 box sealed with K glass, worked fantastic when i tested it while in Cyprus from 1994 to 1998
Thank You! I was thinking about the pvc one but I don't like storing the water in the plastic especially when it gets hot. Just don't trust it not to leech into the water. Copper is perfect!!
Lot of hot water lines are PVC.
Tami Gami
Thank you! I'll be using this in my pool solar heating system.
I recently made a heater from black plastic pipe here in Thailand, as they only use cold water for washing dishes. Something you need to be very mindful of, is the pressure build up if both end are sealed.
I left my inlet to the sink open to avoid any pressure problems.
Nice and simple design, but zip ties will crack in the heat over time. Recommend using copper wire instead. I really like the amount of detail in your videos. Other DIY vid makers could learn a thing or 2 from you. Great job!
Any old appliance should have copper wiring. I usually like to take it all off of old thrown away appliances.
I was also thinking about zip.Your suggestion of copper wire is right.
nuckelhed7 - Also prolonged exposure to UV light destroys plastic zip ties. Here in the south of Spain they last about a month in summer and just fall to bits!
ช
The zip ties are painted black, no exposure to UV.....
About 35 years ago i saw an article in Organic Gardening magazine where a man built a large flat box on his roof and instead of copper tubing he used garden hose. He enclosed it with glass and of course painted the inside of box and tbe hose with black paint. He hooked up the hose to his hot water heater and most days it never turned on and on cloudy days it did so it was a good back-up. His was not as compact as yours, but he had a whole family to heat water for. It was meant to be a permanently in place installation.
I just coil 3 100ft Garden hoses on my sun room roof It is tied into my hot water side of my house . It gets hot enough that we add cold water for showers
Hi , your comment interests me . Hot water wants to rise , and I presume your tank is down . How are you circulating the water that is heated on the roof . I built a hot air collector for winter heating and it works Good , now I'm exploring heating water for summer months , hope to hear from you , Thanks .
Awesome! Thank you! Been noodling putting together an off grid shower, this is the main component! Thanks again!
Just paint your tube in black and the energy harvesting efficiency of your heater will double. (In fact probably more than double). Edit : I saw the end or jour video, the icon you put is a bit misleading. Nice project ! You can also strongly increase the efficency by adding some 45+° mirror on each side of your frame. Estimated gain with 4 mirrors, about 3 times more heat harvested than with only the tube.
Hi Patazertyul...not understanding the mirror addition, how does adding the 4 strips of affect the heat. Surely the mirror reflects the energy back, or do you put the mirrors in back to front.?
Southampton UK
Thanks for these two great demonstration & instruction videos comparing poly pipe with copper tube. Now we really have the answers we need for cheap hot water 😀
Very nice design especially like the use of off the shelf products less cutting less fuss, standard coil, standard fittings nothing overly complex nicely done that man just wish I had your sun to run it.....
My grandparents bought a home in Coral Gables, FL just after WWII It was built with a 15 gallon water heater/ tank with a small 3'x3' solar collector panel. It would give grand dad his after work shower and grandmother water for washing the dishes after dinner. She took her shower in the middle of the day to replenish the tank as she didn't use hot water until dinner.
But it worked for half of the Gables back then.
very cool! - thanks for sharing
I have accomplished a number of solar projects and would like to pass along a couple of comments. First, plastic tie wraps will get brittle in the sun, I would have used copper wire to attache the tubing by stitching it through the holes in a continuous length. Also, I would have made the backing plate out of metal painting it flat black before attaching the tubing to absorb a little extra energy ! GOOD PROJECT THOUGH !
Good ideas. I would add that one should consider up-sizing from 50 feet of copper tubing to 100 feet. This would give increased output capacity. Of course one might also make two or three of these and simply connect them to get the same effect. I'm thinking of having a larger/longer sustained output.
75 degree Celsius really not bad. Excellent job. Good result. I m planning to build solar water heater and your idea inspired me. Thanks from Pakistan
awesome and thank you!
I'm so glad you showed me how to make this, quite the work of art!
I had the same idea to use a roll of coiled copper tubing like that. Only in my design, the coil is elevated about an inch over a reflective glass mirror and the coil windings are separated by about an inch. This way the copper gets cooked from both sides. So you need less copper to do the same job. A tempered glass cover is optional.
Usually, a long tube is placed in a parabolic container so that the focus of the parabola hits the tube. That way you need very little copper. However, building a trench shaped parabolic system is a bit of a fuss. You can get a piece of very large PVC pipe and cut it in half length wise, and line the halves with reflective mirror material so that the two halves focus on the pipe is a sloppy sort of way and get a decent unit that is a bit less efficient than a parabolic unit. Or you can get a Fresnel lens from some old TV sets and focus it on a coil. Use caution as the heat in some well built units is enough to set the boxes on fire. You will also find that your typical hot water heater will rapidly fail with very hot water inside it. They are not built for that heat level. A 180 degree hot water heater should be available as some businesses are required to use them for dish washing and the like.
In order for a fresnel lens to be of any use is if it is bigger than the collector, however, simple mirrors do the same thing and are much easier to aim. As the sun moves across the sky, the fresnel lens would have to be moved to change the focal point. Mirrors are easier to track.
Nevertheless, the biggest obstacle is not how to heat it better, but how to keep it from overheating.
It's also really hard to create good cheap mirrors, especially on a curved surface, and at some point, you might as well just go buy something instead of pissing around trying to make an inevitably shittier version.
The flat mirror idea is dumb, however, as you'd lose a lot of light going straight out the glass you're bounding it back at. You wouldn't get twice the value out anyways, since the copper already absorbed some of light on the first pass. In fact, the better the copper is at absorbing the energy, the less use you'll get out of a second pass because the less light will be left. All of which is irrelevant, because flat black is already extremely good at converting light into heat, meaning very little is wasted by lack of absorption in the first place.
The glass cover may be required in some climates. Some commercial units have tubing that is inside glass tubing with a vacuum between the glass and copper. Imagine air at 10 below zero passing over the copper you are trying to heat. That type of unit can produce hot water in areas with very cold winters. In hot climates i advise people to use caution as the temperature inside a glass covered unit comes very close to the ignition temperature of wood. A piece of wood with a 90 degree edge on it just might ignite. I am not aware of a situation in which such a fire has taken place but it is something to consider. Obviously any system that uses a lens can cause fires if the focus of the lens moves due to wind or whatever.
I fail to see why you think the flat mirror idea is dumb. The solar radiant heat from the sun first strikes the top of the copper directly, then the radiant heat that passed in between the copper tubes strikes the mirror and bounces back into the bottom of the copper tubes. Not all of the reflected heat will strike the copper tubes, but some will, which means its more efficient. Flat mirrors are cheap and plentiful.
I used black PTFE pipe woven back and forth across the south end of my house. a copper heat transfer inside my water tank + a small central heating pump, header tank and antifreeze. works ok in winter too. enough heat for a bath, add electric heater for ten minutes & your heading for steamy bath.
Here is what needs to be built a circuit that kicks on the pump or valve at 165 placing the water into an insulated vessel. You could store the water on site. You would need another pump to give it that closed loop heating so the water in the vessel would take the cold off the bottom and add it to the solar and the heat from that would go into the vessel to the top.
Nice water heater for my pool. Do you know at what speed/rate is the water going into the coil to get those temperatures out of it? Why much time does the water need to spend inside the coil to get really hot out of it? I am trying to build my system with 1/2" copper tubing and would consider replacing the tubing with 1/4" coil, as you suggest to get hotter water "faster" due to the smaller diameter tubing.
I really like this design and it looks simple enough for people to build. Do you put wooden stops on top of the glass to keep it from falling out or does the sealant for weather proofing keep the glass in place?Thank you for such an easy to follow video.
assuming this is for heating water on the go or outside. not bad it will give you quick hot source for camping or rinse off shower
Assuming one is in an area that receives plenty of sun and it's daytime.. nice as a secondary source though.
Great idea. The only thing I would have done differently would be putting a thin black like slate board like a chalkboard or guage 3-6 sheet metal (blackened) where the glass would have been.
This is a great project! Simple, efficient, and inexpensive. One suggestion have you thought about using tile as the backing to gain additonal heat retention. Also tie straps won't last in the heat, small c-clamps secured with screws would last longer.
Again great projector. Great thought starter.
U mean zip ties
مصنع الصاج الملف
@@magicman0867 Some people call them tie straps.
Tile is not a good insulator though so would transmit heat out the back. Wood is a better insulator and helps hold the heat in the box.
This is awesome. I'm building it this weekend to use as a pool heater this summer. Can you please tell me how thick the 20x20 wood is that you zip tie the copper pipe to? Also what are the lengths of the square dowels and what is the thickness of the glass? Thanks!
Great build. You could have a insulated water tank in a convenient shape to fit your van or whatever and store the hot water for use at night.
Nice and simple design. But I would put metal sheet under the pipe - that would increase absorbing surface. Next step - to weld pipe to the backsheet, but that would increase labor.
Good video, pretty simple with very little extras. I like that you didn’t try giving us your life story and talk my head off versus just getting to the point. However, I had a hard time getting past that harbor freight drill you are using. Please invest in a nice brushless cordless drill and throw that garbage away. Thanks.
i'm glad you liked the video! i don't have the harbor freight drill anymore. it didn't have enough power for the tougher tasks. at the moment i'm just using corded drills.
So practical!! Thankyou from Panamá 🇵🇦
you're so welcome 😎
Great job. Fantastic for a Campervan, Camping trip etc. Portable modular cool.
I would add 2 more upgrades: (1) coil background made of metal, insulated to give the heat only towards the coil, (2) mirrors to reflect the additional sun light towards the coil
In Manitoba Canada we use black aqua line ABS tubing any ware in dia. from 3/4 inch to 1 1/4 inch with a small circ pump. i have generally put the coil on the house or garage roof or build a trellis type fence southern exposure is best. no need to enclose the ABS tubing. 65 to 70F water inlet temp produces hot water any ware from 105 to 125F. Below freezing temps system is drained and shut down
Great job... I am always amazed at the comments on how to do it better by people that most likely have never done anything like it at all... Great little heater....
Thank u you for given solar Water Heater manufacturing.Yours projects are so good for student those studding Graduate Engineering
Nicely done, but what temperature is your water going in? You have a 30 in x 30 in box, which is about 0.76 m x 0.76 m. So you're getting about 0.57 square metres of solar access (in fact less, because not all your area is pipe.) The very most you can get from sunlight is about 1 kW per square metre. So your box could get a maximum of 570 watts, if you captured the full area of 0.57 m^2. Let's say you're getting 500 W and 100% efficiency to the water (which itself is a big call as you're not getting 100% efficiency.)
Energy required to heat water: E = m. c (delta T).
m. is the mass flow rate. 1 gallon every 3 minutes is 0.021 kg per second.
c is the specific heat of water (4.186 kJ per kg.K, where K is 1 kelvin, or 1 degree C).
delta T is the change in temperature.
So with 500 watts at that flow rate:
delta T = (0.5 kW)/(m. c)
= 0.5 / (0.021 * 4.186)
= 5.6 degrees C.
But you're getting an output temperature of 75 degrees C.
So one of the following is true:
> your water is going in at close to 70 degrees C
> your flow rate much lower than your estimate
> I completely wrong in my calculations
(Whichever it is, that's a great result and a nice low-cost design.)
I would have thought you could achieve a 30 degree C temperature increase with about 1/2 kg water every 3 minutes. Which is about about an eighth of a gallon.
That's great! Can you tell me what temperature I might expect from this size when it's still cold and windy outside? 10 -15 degreees C. Thanks!
haha
We do something similar on our farm. In winter at between midday and 2pm, the water is warm enough to wash the dishes with..
In summer it is scolding hot for most of the day.
We use black plastic pipe, not sprayed copper.
this is one way to go about it for sure I like the idea for sure. I think if I was going to build one I would build it in a metal box with insulation. to add to the durability and might make it a little more efficient. good job
Should have a metal sheet backing (like aluminum) behind the copper coils to transfer more heat to the coils. Wood backing a heat insulator. This way you can spread out he coil rings a little wider for a larger thermo heat system. Buy dense black paint as used for camo spray paint to increase transfer of heat.
Very nice work. One comment: I predict that, over a fairly short time of use, the zip tries will break down and crumble. Wire would be better, with a layer of IR reflective insulation behind the mounting panel would last longer and perform better.
use the black zip ties they are uv protected
Of course I dont know but he could be alluding to the repeated heating and cooling not the uv.
+LFOD
Using plastic to secure the tubing is better. The problem with the zip ties is they will become brittle and be prone to breaking easily.
If you use ferrous metal strapping instead of copper, you run into the danger of electrolysis occurring. Try using copper wire instead. 10 or 12 gauge wire will work just fine.
Electrolysis can only happen if the water is in contact with BOTH materials.
In this case the water only comes into contact with the copper, the wire (or whatever you use) is only touching the outside of the copper pipe, so it does not come in contact with the water.
I have found that even the high heat zip ties give up surprisingly quick in the direct sun. I went to bailing wire.
I did this with a black garden hose worked great and cheap
Great simple design. I would add a pre-filter at the head end of the water input.
Your projects are so very helpful and needed. Thank you so very much. Your family is blessed to have you, as are we. Great video.
I made something very similar about 15 years ago with my dad when he was alive and retired. Not as pretty as yours, but it worked well.
In this demonstration what was the temperature of the water before it went thru the copper coil?
Nice project.
Bottom of the heater should be from metal like aluminium or better copper.If choose copper should painted black for absorb and radiate back more heat.
If choose aluminium make it shining like a mirror.You gate more heat .Or get some aluminium foil and wrap all plywood in aluminium foil.
If you get some aluminum chips from a lathe operation, get the oil off , and paint them black you can increase the active surface many times over and get much hotter water easily. I think you would be shocked at the heat gain.
"you can increase the active surface area many times over"??
Um.. no you can't. There is only so much light per area. Any minor additional reflection that you'd get from painted metal chips would be quite negligible.
Maybe you can post a side-by-side video of the two styles.
If he does, you will see how negligible his erroneous claim is.
+Justin Bozeman
Unless you get insulation for free or you have some laying around gathering dust, insulation won't be of much use either. Glass or plexiglass won't hold the heat in for long & the thermal mass of rocks/pebbles isn't very high (which means you wouldn't get enough extra heat from them to make it worth your while for such a small volume of space & for such a small thermal difference between your inside temp & the max temp the rocks will reach.
If tubing was fixed to cement board, would the board become a heat sink?
Thinking about putting copper tubing coil in a water tank. The hot water will circulate through the copper coil heating the water. When the water gets hot the circulation will stop until it cools or you use some hot water putting cold water in.
The water will be heated using coraplast with water running through it from a pipe on one end out of a pipe on the other end.
great ideal. use a lot of on the roof. thing is, you probably get great hot water by noon when the sun is apex for a shower. the rest of the time warm water is good for dish washing and such
Just curious on how you would control the temperature, remember that we usually set up the heaters around 120 F to avoid scalding, I found this same set up in older building roofs for the same purpose but they compliment them with mixing and control valves.
Thank you for sharing your experience, it's golden.
However, I'm wondering could you get better result with no space between copper circles. In summer it could not be matter. But, in fall or winter air around copper can make them less warm. If no space between them, they can share own heat with inner or outer circle too?
Also wondering, if bigger copper tubes could get more heat via more copper surface = more heat?
Thank you for your time,
Mehmet
Awesome video man ! But why not put a reflective sheet of metal under the cooper pipes ? ...you know...for more energy (?) :3
The idea is that you do not want the sunlight reflected back out to the air....you want the light to be absorbed and converted into heat. I wonder if just using black painted plywood would be as good as painted aluminum.?
I like my idea of a black tank of water with either air pressurized or gravity fed...but it does need bleach cleaning (or added) now and then.
Nice video demo👍
This is awesome I instantly started thinking how I could take advantage of something like this and my first idea was to use this to pre heat the water in to an electrical water heater on a hot day the thing would barely need to work at all
es muy interesante la forma en que has resuelto el problema de las soldaduras con estaño pero¿cuanto metros de caño has usado en este proyecto me gustaria saberlo..saludos de un amante de la energia renovable.
Thank you for sharing... Love your shared ideas and knowledge through videos. Great work!
thanks much ✔😎
Thank you for sharing. I'm in Indonesia (7°south) these ideas can have great use.
Makes sense doesn't it! My father had a swimming pool built and had the return water pipe buried underground. I asked him why he didn't have it go up and over the pool house in coils so the sun could heat it up. The look on his face!
I think what would be helpful is taking a mirror or mirrors pointing to the water heater would surely help to heat the water
I just did something similar as well. I left my black hose in the grass for a day. Its about 300 ft worth of hose. When I spray that puppy boy I got me some hot ass water!
So a couple ideas I was thinking of. Im going to make one of these and put on my roof of the garage which is right above my pool but 1- if i cover the back piece of plywood with aluminum foil and then also attach multiple magnifying glasses on the inside of the plexiglass before sealing it....would I get more heat? 2- do you recommend copper tubing or pex?? Which will get more heat?
Thanks - as soon as I get the needed parts together (luckily most seem 2 b lying around) will try it - VERY interesting approach
That copper is pretty pricey. Any chance a similar sized black irrigation tubing would work just as well? Or is the copper conducting heat better?
hi there. copper really is the better choice. black tube usually only handles up to 180F. plus copper lasts way longer - 50 plus years verses maybe 3 to 5.
Any thoughts on painting the wood black?
@Howard Stymiest The best thermal performance approach is a copper sheet bonded (soldered) to copper tubing. The tubing runs in a back-and-forth pattern, reducing the distance the heat has to travel in the copper absorber sheet. Then apply a black, high-absorption coating. Paint is not the best coating, however it is low-cost. A 'solar' paint would be best.
Plastic degrades in sunlight. Adding carbon black (hence the black color) helps a lot, but it will still become brittle over time and crack or blow out at some point.
The desired properties are high thermal conductivity and corrosion resistance. Aluminum is an option (excellent thermal conductivity) and steel would work (not as well). However, any time you mix dissimilar metals (copper with aluminum or steel) you're going to have corrosion issues - look up "bimetallic corrosion" or "bimetallic corrosion table".
I am considering building a few of these for my pool, it's 30,000 gallons, so I figure maybe 12 or so. I'll have to do some figuring for pipe and pump size, run a single pipe up the roof, maybe 1"to, 1 1/2" pipe to feed the banks from a home made copper manifold, Then back down the roof in a larger size pipe and manifold. We used 1 1/2" up and 2" down, back when I installed solar pool heaters for a company here in California. I need a cheaper alternative, like this.
i done a smillar thing when i went camping but i put the copper coil in a 44 gallon drum that was our fire pit with a little 12v pump
Hola, Se le tiene que colocar un vidrio a todo el cuadrado, para impedir que el calor no se pierda. Saludos
really great idea.copper tubing is $120per 18m here but still worth it long term
what is the size and where do you get this $120/18m. Thanks for your info
Is it absolutely necessary to use copper or would black rubber pipe do the same at a lower cost ?
Also question = waterproof box and fill with antifreeze or use a 2nd larger diameter pipe and fill the void with antifreeze??
You might consider an inline venting valve to help purge air pockets between uses.
Thanks, I'm thinking of trying this and using a small aquarium pump from my pook and heating the pool water. and returning the water to my pool.
If you want an easy demo simply coil a garden hose on the pool deck and you may be shocked at how hot the water gets flowing through the hose. Simply keep the flow rate low and you could even use the pools filter pump to send a trickle through that hose whenever it is turned on.
Hi there i have just found out about a thermal heater and honestly know nothing about them, im wondering is it a continuous flow of hot water all the while the hose is running or is this limited please? Any advice would be great, also how exactly it works, i imagine solar power, does the solar energy store in the pipes? I honestly have no idea :s
Definatelyintersted in making one if it could fit the means i have in mind for it
Thanks
How many gallons does it put out before it goes cold? Does this work in 32° weather?
Will this fill up a bathtub?
What about fire hazard?
Does it get so hot (in the summer) ,would it catch on fire?
Love to make one.
Zip ties wont last you, use stripped bread ties or metal wire. Also paint the base of the copper coil black. If water hot water needed at night placing the coil atop a rocket mass heater will do the job for which I would suggest a tube-shaped coil inside a coffee of paint can insulated. I like that you used glass but I'd recommend maybe tempered plexi glass.
What a fun project this was! I paid a little extra to have the wood pre-cut & assembled, and saved a lot of time as well.
Did you have that done at a box store (HD or Lowe's)?
Do you get a thermosyphon effect with this construction method or do you need to provide pumping?
Whoops! This guy is doin' it right!
You could use all that copper tubing to circulate hot water through it and have a fan move air through it to heat the air in a green house or home. Super easy!
This is a good idea as a collector, but You need to store the water and keep it hot so the water need to be circulating inside of a water tank. This is just part of the job , but maybe I am am misunderstanding.
The water storage is a whole separate topic, I think it makes perfect sense to have one video on collection and another on storage.
Do not try it with a home hot water heater. They can not handle the degree of heat that collectors can produce and will rapidly fail. You will need the 180 degree water heaters required in restaurants. It would be better to make your own storage system but it would be quite a project and require skills most people don't have. If you can find a stainless steel tank with a large enough capacity it is a good start and then add a shut off when the water gets too hot. You can actually produce boiling water in some collectors.
any water heater will do the same job. the only constraints are the capacity (GAL) and the pop off relief valve ,remember warter boils at 212 and a hotwater heater then becomes a boiler and steam pressure is alot higher can be very dangerouse at that point.
That is not correct. There is a huge difference in the materials that coat an industrial water heater that must reach 180F and the water heaters that you buy for your home. The coating on the inside of a home hot water heater will decompose quite quickly when exposed to water at 180F. You can see the difference in the prices charged. Get a quote on a 180F heater at 40 gallons and then get quotes on home water heaters of the same capacity.
You can use a home water heater if you add the hour water with a bit of cold via mixer valve
have you considered heating it with a Fresnel TV lens? off focus so you don't melt the unit. auto tracking the sun is a relatively simple circuit I've seen a couple vids. I am curious, always have been, does painting them black increase heat absorption significantly?
Using a parabolic mirror aimed at the copper pipe would increase your heat transfer tremendously.
Or a Fresnel Lens (at the proper focal length of course)
New Doctrine Equals Heresy
An Aluminium sheet bent into a parabola and focused onto a 5 cm diameter copper tube will produce boiling water, and the reflector can be made to turn slowly round the axis of the tube to keep in focus. The tube could be filled with oil and pumped through a heat exchanger - or you could run a steam engine off it!
won't that melt copper pipe tho?
Cottage Gypsies
Copper melts at 1080 C, so it would be safe even if the water flow ceased, and would be more likely to melt the brazing alloys or solder first. Or set fire to the casing. For most purposes , flat-plate collectors are enough for domestic hot water, though a pumped system with a longish copper pipe and curved aluminium parabolic reflector would give improved results in high latitudes.A sheet of aluminium 2.4metres long, curved with supporting profiled braces, and a 2.4metre 50mm diameter copper pipe at the focus would potentially give higher temperatures. See "sgirrel" UA-cam clip for an example.
There are many possibilities, depending on needs, and the parabolic reflector could give you water hot enough to drive a steam engine, pumping oil through the copper pipe instead of water, and using a heat-exchanger.
wow, your smart....i didn't even understand most that answer,,,i appreciate you taking time to explain it tho..but i do know now, copper has to be very very hot to melt...lol.....thank you, have a great day..
Nice vid, thanks for sharing. Although you might want to coat the Perspex with 303 aerospace av protectant to stop the Perspex deterioration
what about evacuating inside so interior was in a vacuum ?was watching vids on evacuated glass tubes and thought it would be easier to do a box.what do y'all think?
How about 2 fold out doors like a dart cabinet with mirrors on the inside to reflect more light in? Perhaps with adjustable arms or chains to hold in place. Just a thought.
I'm doing something similar, only with about 160' of 1/2" poly tubing. I'd like to use 1/2" copper tubing but that's all too spendy. Yours does look good, well done.
A heat exchanger/radiator from an old broken down car can work well as a heat medium if you don't have tubing in excess.
+McGaughey that's a good idea! Could a plumb a load together all tightly, paint the sun side black with a sheet of glass over the top? would look tidy aswell
I have an idea that i have not seen anyone try yet. There are numerous videos on U Tube about solar hot air collectors. They are cheap and easy to build and the temperature inside those collector boxes get quite high. A small copper coil could be combined within those collectors to heat water. One advantage would be protection against freezing as even at 20F these hot air collectors get above 120 F easily. If the air around the copper coil is 120 F or more you can bet that the water inside that coil will be close to the same temperature. Besides being far less expensive to build the units would also be lighter in weight. Simply view a hot air solar heater or two on U Tube and think of a copper coil at the top of the box.
+Jim Sadler I think we need a giant man shed lol
Pop's Shack the problem with the poly tubing it doesn't conduct heat well so it will suck as a device for that reason
Great Would you try to use a Fresnel Lens but to calibrate it in a way that the sunlight rays focused on the Copper coils only and Let's See how much the water temperature can be increased ?? 10x great video.
great video
I remember this guy who had a. Giant(4' across 18" deep ) bird bath looking thing next his pool that had a huge copper spool in it. And his pool pump was hooked up to it and his pool was a jacuzzi it would stay 100° like it was nothinhg ..... His uncle was a contractor who put the pool in and didnt want to pay to heat the pool ...he lived next to phoenix college ....
I have a 30’ round above ground pool in maine. I wonder how many of these I would need to extend the season. My husband built a larger one with black plastic and similar design but only get 90 degrees F ?????
How long will it heat the water while in the sun? Does it get cold at some point when the flow is on all the time. You need a storage tank and a circulator pump.
Hi and I am making the solar water heater as a "closed loop" for my hot tub. I am curious what or where I can find the suitable pump (preferably off the solar panels or battery) that will drive the water through the heater. Any ideas on what to do next AND also what did you use as the glass part? is it tampered or polycarbonate and thickness.
Thanks for the information and hope to hear from you soon as possible.
I am thinking of doing the same thing with my hot tub. Electric bill is killing me. Looking to do somthing like this to preheat the water. Want to share notes. ?
Sure! Only thing I am doing is using the sun to keep the hot tub from running on constant basis and as well as heating it up.
I'd appreciate any advice or information on this. I am looking for a solar power capable water pump but don't want a HUGE one as the water needs to heat up before it comes out.
Thanks
Great.. Email me at karl.goebel@gmail.com
So cool ! And it is visually pleasing, too !
would the spiral coil inhibite a natural thermal siphon effect of natural flow of in-thru & out without the water pressure from a hose ?
this is awesome, I think it could be slightly improved if you used some reclaimed sheet metal to attach the copper tubing to as well as to hold the heat for longer durations. thanks for the tutorial!!
And install insullationboard underneath the sheetmetal you attatch the copper tubing to
What's the volume versus the flow? or is it contentions heated to 150 degrees all day long if it is a flowing. Or, are we talking about a gallon of hot water heated up one at a time? AND if so what's the time to heat to 150 degrees per gallon. , Just a wondering if you could take a long shower or is the flw to slow.