Bottom Update: I \'ve been interested in solar projects for some time now, and I came across an \"aluminum tank solar air heater\" a few years ago \". I thought it was a great building built with some scrap material and vowed that I would build my own one day. After all, I have a big, unheated space that can benefit a lot from some free BTUs this winter. I studied several buildings, explored what materials I could get locally, and thought it was time to build one myself. Then I had time to think about it. . . . The idea is very direct. \"Building a wooden frame with foam insulation -- Board, apply the interior to black, use a shield to catch heat, and then cover everything with an acrylic sheet. The idea is simple. A closed box, insulated from the cold, takes the air from the interior and heats it by absorbing the energy of the sun. Once heated, it sends warm air back to the room. \". What is easier? It\'s true that we ended up with a wooden frame, but we added (2) The type of foam plate, the concrete back plate as a heat sink, and the way to install the screening is too complicated. I found the original design on the net combination sleeve of the aluminum tank and some kind of baffle. The jar is painted black and when the air is uploaded from one sleeve to another, it is heated before it is returned. This design works well, but there is a problem with surface area and heat transfer. One of the questions I read about this design is that there is a big air The space between the glass and the top of the jar, which is not mixed with the air passing through the jar, wastes a lot of thermal potential. I then stumbled upon some buildings and suggested to install a simple charcoal \"screen\" on the collector as it has a larger surface area to interact with the moving air, so it can also work or be better. I certainly believe it means more and better, so I came up with a wave beat on the screen. In order to increase the solar absorption area and the surface area interacting with the air, the screen fluctuates up and down, from top to bottom. I also want to include some kind of radiator. The thought process goes along the route of being able to maintain heat radiation to the air in the case of a brief drop in sunlight. The first thing I thought of was bricks, rocks and other similar materials, but they were all too heavy -- Guess how it will benefit overall output. . I chose a thin concrete. board. It would be great if it succeeded. If not, there would be no waste. Finally, for no good reason, I decided to have an air passage behind the collector. The reason is \"pre- Before being introduced into the main heating area, heat the incoming air against the back of the heat sync. I think the back of the board will be hot, why waste heat, why not put some air on itCharge it a little. Again - I don\'t know if this really happened at all, even if it happened, if it\'s worth the design trouble. I think once everything is done, I should probably build the next one without this feature. Simpler, easier and deeper areas for additional screening materials. Apart from the part where I stared at thinking about design in the distance, this is where the project actually started. I would sit down with some paper and start sketching out what I think. I found this to be a great way to work out the design, assembly steps, and bill of materials. I will go through many iterations of the design when drawing the design, which helps to make the final build faster and smoother. However, there is a dark side to the process. Constant redesignNoooooo! Give me enough time and I will find ways to make things \"better. Yeah, better. This usually takes an excessive form. Complex, special material needs or needs one- Specialized tools. It\'s a weakness, but it\'s the way gray matter works. I\'ll finish a design, all the pride and joy, and then I\'ll hear Dad\'s voice, \"Simple is elegant, simple is clean, why is there so much complexity? \". Soooo, this is probably one of those less simple designs. Spent too much time between design and redesign Design and several other Re Until I got the material and started piecing things together. Having said that, I like every step of it, and when I make the next step, I will combine what I have learned from this step. For their value, my advice is: material: the first piece I bought for this project before I really thought about anything was acrylic. It is 36 \"x 72\" x1/8 \". This, of course, is the reason for the size of the frame. I make the frame itself 1/4 larger than the acrylic sheet so I can router the edge. I want the sheets flush with the edges of the wood. I fixed the frame together with a Kreg fixture drill screw fixture. I also measured it with some building adhesive. Note: The Extra build will use the pigeon tail fixture to assemble the plates together. It is closer and more structured than screws and glue. Once the square is good, I clamp the bottom of the plywood with the pipe. The bottom of the plywood is fixed with the same adhesive and some small cloth. It fits flush to the bottom of the frame due to the routing edge. I also took the opportunity to cut two 4 \"holes on the plywood towards the bottom of the frame. These are used in and out of the air flow. At this point, according to my drawings, this is an estimate of where they will go and how far apart they should be. Material: \"Why are there two types of foam? Very good question. A mediocre answer. I used the 1/4 foam board to isolate the bottom and sides of the box. The 1- The 1/4 \"foam will also be used to heat the bottom and sides of the insulation, but will also be used as a structural support for the mountain Board and create waves in the filter material. Note: I cut the thin foam with a utility blade, but it would be better to cut the larger foam with a small tooth Wood saw. I\'m also in a vacuum (must have) Hold a soft brush head on your hand and suck off the millions of pieces it kicks up. I did use a long blade on a few pieces as the screen angle, but they ended up not being as square as when the saw was used. I fixed the foam on the wood with building adhesive and the foam on the foam. The other two reasons I use two layers of foam are because of the mountains. Boards and vents. The backer- The board is placed on the top and bottom of the thick foam and docked with the thin foam. I don\'t want it to lean directly on the wood because I want it to keep as much heat as possible. Another reason is the vent. Its lips are sandwiched between the two sheets to help it say it is kept tight. The thin foam didn\'t lie flat, so I ended up using some weight and didn\'t lie down flat until the adhesive was dry. I also used a bead on all edges to help keep it sealed. Oh yes, don\'t forget, don\'t poke your finger with a knife, everything is bleeding. Material: This step is very labor intensive and a bit painful. I had to cut a few \"1\" straps from the big foam sheet, which required a lot of dust-sucking all the debris. If that\'s not bad enough, I\'m the hardest to get support from silver tape. A lot of tape, lack of light, bad eyes- I have to keep reminding myself that this is a pleasant thing! Note: I\'m not sure if the idea of air passage is totally worth the time. It sounds good to me, but maybe someone with better engineering knowledge can help me make this decision. I first tied two 4 \"vents to the foam. This creates an airtight seal and covers the exposed edges of the foam. Note: I want to cover all exposed edges of the foam. I believe they will deteriorate over time if exposed. I then cut a bunch of 1 \"strips from the big foam board and built the air passage and edge lining. I glue the tape and silver tape down with adhesive to cover the edges of the tape exposure. I also sealed the gap between the tape and the foam board with the tape. The back panel will have vents that allow air in and out of the channel, so I have widened the top and bottom channels to allow these vents. Finally, I created an aluminum plate ( Several pieces) And stick it to the top of the channel. I\'m worried that the supporters are not treated. board. I don\'t want it to throw the material into the airflow. Note: Yes, so maybe by limiting the airflow to a narrow channel, I reduced the expected transmission capacity. If I keep this feature in the next release, I will allow full air transfer with some support bars, not only to help support the support -- Plate, but also helps to stir the air to prevent smooth flow of air. Material: The purpose of using a concrete back panel is to act as a radiator, helping to dissipate heat evenly when the cloud floats. I also hope that when the sun goes down, it may extend the decline in heat. Note: Perhaps, if this is indeed a good idea, it may require thicker/denser material. What I am worried about is that the 1/4 board is too thin and has little impact. Or perhaps not. After measuring the vent, I drilled some starter holes with a drill bit and then used the clamp- Saw cut out the vent I cover the edges with silver tape and seal the seams with adhesive. Note: I read somewhere that some backplates have fiber problems that can cause health problems, so I make sure to coat all exposed surfaces with tape or paint. Note: Again, if I do a second build, I will expand the vent to the entire width of the board. I fixed the plate with adhesive on the foam stripe material below: I wanted the outside of the box to be consistent with the elements, so I chose the exterior oil-based paint. I wear several coats to make sure the rain and snow will (Fingers crossed)minimal impact. I also sprayed the mountain-board with hi- Temperature painting can not only absorb sunlight, but also seal the fiber. Note: Next version I may choose the brush app in matte black. I have a few examples and I have also painted all the other exposed surfaces with matte black hi- Temperature paint when their pieces are cut. Material: Note: Since I still have a roll, I used charcoal fiberglass screening in this project. However, I was thinking that it might be a good idea to use a charcoal aluminum sieve. Not so tolerant when bending, but better heat transfer, life may be longer. The first step is to cut the thick foam board into an internal boundary of the shape so that they can be placed on top of the Hill -- Board, but even if there is a bottom routing edge at the top of the board. On this issue, believe me, be sure to mark which is which. Then I cut the edges into triangles. \"Bottom\" triangles are those that are connected to the mountain by the flat sideboard. I just painted these in black. Those flat sides facing the plexiglass, I covered all exposed sides with silver tape and also painted black. Note: I don\'t want to chatter on this issue, but to number the work. Yes, you will mix the order together, yes, it is important, yes, it will bring you a certain amount of sadness and frustration. The original idea was that the foam triangle would have enough material to force the screening into waves. This quickly proved to be an incorrect assumption. Quick cleaning of available items, I have a copper shaft and some small screws. I used the balsa saw to cut a small slot at the location where each screen peak was located. On the one hand, I screwed off the wire and pulled it tight --ish. I wrapped the wire around another screw and tightened it. It tightened the wire when the screw turned. Note: do not tighten the wires too tightly. When the screw itself turns, it continues to wrap the wire. Too much pre- Tension and wires break immediately. Too much, will crash soon. It takes long enough to support the screen, no longer needed. Once I have taken a few photos, it is not difficult to judge. I put the screen on the floor and cut it to fit inside the form. What I will do next time is first make sure there is no foam film on the floor. Wow, does this thing attract foam like a magnet? I have static electricity on my ass. After the wire was installed, the screen was actually installed without much fuss. I bound the top of the screen and then used gentle tension when I first expanded. I used a fair amount of adhesive on the first triangle and pressed it in place. The adhesive flows out of the screen and locks it in place. Note: When Everything dries, I fix them in the proper position with a long push needle. The pin not only keeps the foam in place, but also keeps the tension on the screen. From left, right, top to bottom, each triangle falls in place and everything bends up and down if you\'re lucky, no problem. The wires do a good job of keeping the top curve form. I nailed the screen to the bottom like the top. Warning: measure, test fit, then measure again. I thought I measured and tested well, but the side of the triangle was too high. In the next compensation you will see what I have to do. Material: When I framed the box, I initially tested if it would fit the acrylic sheet, so I was fairly confident it would still fit like a glove. Wow, I was wrong. the more I thought, the more I should have expected the problem. The problem is that when everything dries, the top of the board is slightly bent. Note: If I install a few pieces of tilted steel, the top of the box may be properly aligned. They handle the curved expansion of the screening well and prevent the side from twisting. Lessons Learned. I cut the sides of the paper with my Dremel so it can fit into the wiring edge of the frame again. I used a couple of cutting wheels but next time I will choose the wheel with the small teeth. Cutting wheel caused by high RPMs (toothless) Just melt the paper that is not the best solution. Yes, the sheets fit the gain! No, the sheets are not suitable! Yes, that\'s where the misplacement problem comes again. The side of the triangle is a little higher than it should be, and the paper pops up from the frame. I tried to crush the foam a bit, but sadly it\'s not like that. Note: Check which adhesive you pick up. I am using a white but dry transparent tube until I pick up a new one to paste the transparent one. The tube is of course white and dry white. I applied a thick layer of glue around the frame so that when the sheets were on it was smooth and made everything unbreathable and non-leaking. This step will be much easier if you have someone to help you. I used a wooden screw with a washer to tighten the paper on one side. Although the screw head is a bit too high, it keeps everything flat. I will use more flush screws next time. Because I used the wrong adhesive, I covered the edges with silver tape and covered the white color. It can also cover some foam edges and keep the adhesive in direct sunlight. I don\'t think it\'s such a bad mistake after all. Material: OK, it\'s all together. what about now? First day: first Test, I was not able to take the unit out of the \"awesome building pit\" until later in the day \". At about six in the evening, I leaned the unit against the garage and plugged in a small fan. I used a 4 \"box fan salvaged from an old computer with a circular PVC reducer on it. Perfectly installed in 4 \"tubes. I attached it to a 12 v adapter and put it in the temperature probe. Wow, it\'s so hot. The temperature rises to about 120 degrees and then to about 135 degrees. The temperature outside is around 87 degrees and there are some light clouds. Not too shabby. . . Day 2: At least this time I was able to start earlier in the day. The temperature was around 87 degrees, but it was already two o\'clock P. M. The clouds are a little thick, but the sun is shining. Again, WOW! The temperature rose again, but this time it exceeded 170 degrees. I think hot sinkidea might be a good idea because although the temperature drops a bit when the cloud goes out of the way, the drop is slow and the recovery is fast. Okay, maybe I just got some idea of the last part. ----------- Either way, the temperature difference is very good, I hope that in the cold winter, the extra insulation in the box will remain as high or higher as the difference. . When the weather gets cold, let\'s see what\'s going on. I have a roll of 4 \"insulated tube ready to connect it to the unheated space. Update: I have changed the 12 v PC fan to the 120 v Online 4 \"pipe fan. Move more air, very quiet and will not run out of a lot of juice. If I can find a similar DC version, I might change it back because I prefer to use solar cells ( No inverter) Power the equipment. CAN\'T WAIT! ! The stars were neatly arranged and the weather was fine, I found some free time on the schedule, so I decided to turn my heater on and see if I could get it up and running. It\'s been a pretty mild winter so far, but I \'d really like to get it running and see how good it is. Coincidentally, this is also the time when all the shortcomings begin to appear. At least my second version got good data! ! ; -) Before I go into \"I\'ll do better next time\", let me start by saying that this thing will release heat! With a lack-luster fan ( OK, lower gas driven blade blower) It is still able to maintain a healthy 30-degree output temperature on a sunny 30-degree afternoon. Although Poly feels warm, the box itself stays cool, so I didn\'t lose much heat in the process. The tubes are cool too. The colder weather and more constant air throughput are a huge test. Question 1: How to get air into the room plan is to always get air in through the window in the basement, but I\'m not sure how I\'m going to get through the glass window. I was \"prompted\" to find a solution when one of my windows was broken (don\'t ask) So I built a new wooden frame with polycarb plates and cut holes for my two flanges. Fit like a glove. A question. Question 2: What pipe does AIRI use to pick up some insulated 4 \"flex pipe on my LHS and fix it on all my flanges. It consists of an internal spring tube, surrounded by fiberglass insulation and covered in a protective case. It should be waterproof and should \"help\" to keep the heat flowing. What I am most worried about here is that the end will turn into water. I used some silver glitter glue to bring the end of the package and then zip Tie everything up tight but the water goes to the end so I\'m not sure what permanent solution I will get. Feel free to make suggestions! Question 3: In my initial test I used a 4 \", 100 CFM pipe fan that worked really well. I\'m such a fool. I have learned more since then and now I know why that fan is not suitable for blowing candles. Static pressure is the force generated when the air passes through the system. The longer the pipe, the more twists and turns the air, the more \"push\" the air needs to move. This small pipe fan cannot work up the hill with all the extra pipes. The impeller fan has a large gap between the pipe walls, which allows most of the airflow to blow back through that gap. While the blowing machine worked fine as a test, I decided to pick up the VenTech online fan. Easy handling of static pressure. Question 4: it\'s cold at night! Damper. Need a damper! Since the main unit is above the basement, convection current is generated at night, causing cold air to return through the feed pipe. Since everything is in \"manual\" mode at the moment, I just fill some fiberglass insulation in the tube when not in use and seem to do a good job. However, I\'m really looking for something that automatically turns off the airflow when not in use. ( Oh yes, it will also increase the static pressure). Question 5: automatic, I have this! I have an Arduino and several temperature sensors that I use to automatically turn the fan on and off when the box temperature rises and goes down. I have written the \"most\" code and the sensor is soldered to the RJ45 cable end through the feed pipe. It should not be a problem. It will wait until the box is several degrees warmer than the basement and then start blowing, and it will continue to blow as long as it is warmer than the basement. If it stops for some reason, it will wait again until the temperature of the box rises a few degrees and then re-starting. In the end, I want to connect this system to the Raspberry Pi solution I\'m currently using that combines mySQL with Python for beautiful graphics, etc. Question 6: What do you do when you don\'t want to get hot? Connect and open at the end of my connection (pitiful) Van, I tilted the heat box to get the best exposure. There is some moisture in the box that condenses inside Poly. When I removed the temporary vent cover, a lot of steam came out. It\'s hot inside. I\'m not worried about summer coming, but what happens if I don\'t need to run the fan? How much heat can this thing handle without breaking? For now ( As long as I start and run automation) This shouldn\'t be a problem, but it will be a problem if it stays in manual mode, or if the internal temperature gets too hot, and the thing starts to melt. Temporary solution, throw a lid on the box. Ugly, but effective. Long term? I think there needs to be some kind of external cutting -- Deliver air through the box and then ventilate outside to prevent it from melting. Question 7: Do you know poly? Is CARBONATE still vacuuming? The box in the garage was put for a while and it attracted some dust outside. Filter the air into it! ! If you pass the air through the box without a filter, it will start sticking to the inside of Poly. There is no removable top for this beta version, so there is no way to go in and clean it up. Yes, it attracts every piece of floating dust. The last issue: it\'s really just a reminder. If you\'re going to put a box somewhere, make sure you check the sun is plentiful all day. I was very happy to pick my location. Southern Exposure close to basement windows etc. . Found a tree blocking the \"some\" Sun later in the day. This is not a show stopper anyway, and I will still put it in the same position considering all the variables. Remember if you want to put one. Sunny is always the best, but even later in the afternoon, my box is still sending out heat because a tree with no leaves now casts some shadows. Hey Folks! There\'s nothing but cloudy in the last few weeks, so it\'s a bit difficult to test everything, but I\'m sure we \'ve found something interesting. Automation: I just finished the Arduino temperature control system. For such a system, it is absolutely necessary unless you are sitting next to the on/off switch all day long. Cloudy weather can produce an hour of sunshine, which is enough to generate some heat. Everything is lost without automation. When I\'m done, I\'ll post a note on the Aurdino controls. Screen vs CAN method: I like the idea of the screen method to allow most of the air to come into contact with solar absorbing materials (screen) The tank collects all the dead air between the tank and the glass. Maybe the can method is not so bad after all? I would like to know how much heat is lost because the only thing between the hot air collector and the outdoor cold air is the organic single peace. I want two side by side to solve this problem. If I use an enhanced screen collector, maybe there will be more expensive insulated glass for the next building. Screen surface area: I \'ve seen designs that use a single, flat, reclining screen, so I thought I \'d run a bunch of hills and valleys to collect more heat. If the box points directly to the Sun at any time, then more peaks are equal to more surface area to absorb heat. However, if the box is installed statically, then too many peaks and valleys will prevent the sun from hitting only the top of the folds. How much heat does this really put: this is where rubber meets the road. I had a really sunny day, so I had the blower open from 9: 30 am until around four o\'clock P. M. The temperature outside is in his 30 s. Based on the PI box I monitor the temperature and humidity, the best thing I can do is heat it up about 2 degrees. My basement is usually in my 50 s in winter with a humidity of about 40%. Depending on the increase in temperature and the amount of air that has to be heated, I ran a few numbers. My calculation for the day was 2,400. This is a large basement with 14,000 square meters. I believe the numbers are correct, but I am not 100%. Length, width, height and temperature increase over time. Glue is not the way to go: I fixed my plexiglass lid on the box with building adhesive. Come out one day to find the top corner (hottest) Has stopped, is the wind (and water in). I fixed everything with screws and washers. Next, I will use less glue and make sure I have mechanical fasteners as much as possible.