Excellent video and excellent set-up! Thanks for sharing! This is the best set-up I've seen so far. I love that you didn't use a submersible pump, and your temperature controls protect the hot tub. I wish I could find instructions to build this sort of thing. I'm savvy enough to set things up, but not quite savvy enough to be able to figure out the equipment I would need.
Thank you Brandon for the compliments. Let me know if you want to build it, we can get in touch, I can send you a diagram and help you over the phone. The hot tube has been a blessing for me, best thing I've done in my backyard.
Thanks Marc, appreciate the info, glad it’s all still running well, I only use bromine in my tub so that’s good to know. I set mine up last month (Spain) and found that whilst it will maintain a temperature it won’t increase it unless it’s a hot full sun day, pretty sure it will work well from April though.Now looking at doing something similar for our domestic hot water. Thanks again for the reply. Barry
I hear what you are saying Marc but if I set the sensor in the panel to switch on the pump around 130f and the sensor in the hot tub to switch on the pump to circulate water when over 98f that should prevent overheating the pvc, the issue would be if water is left to boil in the panel. I'm also looking at the possibility of using a 12v valve to allow the water to be 'dumped' via gravity into the hot tub when the set panel temperature is reached, this way you get all the hot water from the panel instead of using cooler water from the tub to push the hot water from the panel, just a thought at the moment. Thanks for your help, it's appreciated.
I use a 12v 20 dollar hot water recirculating pump on its 3rd year that runs direct drive from panel no thermostat. Adjusting water panel to semi regulate temperature. Non stop for the 3 years.
wow, non stop for 3 years, that's amazing for a $20 pump. Of course if you used a thermostat you would be able to exactly dial the tub temperature that you want without having to adjust your panel. Over the top water temperatures in your tub might harm plastic parts and lead to premature components failure.
I like it. I'm trying to figure out if I should couple my collectors and thermal heat exchanger into the electric system. I do like the independent system idea too.
Marc, 2 quick questions: 1. When the thermostat hits the low set temp and switches the pump off what stops the water in the collector flowing back into the hot tub? 2. I like the concept of monitoring the water temp in the hot tub to ensure it doesn't get too hot, but I can't figure out how you have it wired to isolate the pump when you have the pump connected to the other thermostatic switch? Sorry if that sounds like 2 stupid questions but I really like the idea of the pump only circulating the water when it's hot enough, it has to be better that constant circulation and want to get it right first time.Barry
I can't figure out how to send you a diagram on this, but I will try to explain in words. For your first question, I added a check valve about 3 feet after the pump outlet. It's a 1/2" brass check valve from home depot. Make sure it has the teflon inside because it makes a better seal. It does a good job keeping the water in the panel despite the gravity of the hill. For your second question, both of the switches are wired in series. So the wire goes from the 120W solar panel to the first switch to the second switch to the pump and back to the 120w solar panel. Both switches have to be closed at the same time for the pump to turn on. If not at least one of the switch will be open and no current will get to the pump. In this case the water in the panel has to be at least 140 degrees and the water in the tub has to be below 106 degrees. If one of those 2 conditions is not met, the pump will not turn on.
I got my first hot tub about 4 years ago it is just as a portable inflatable hot tub or a kiddie pool on steroids but I really like it I have considered doing this that you would probably damaged my tub being inflatable vinyl that looks like a fun project
It was a fun project and still working well. It's not going to damage your tub unless you let it get too hot. I have my thermostat switch that cuts the system when the tub reaches 106F.
Great video thanks, in this setup does the solar heater take the water from the tub to reheat? Or is it connected to fresh water supply? If so how do you deal with overflow? Also what happens if the tub is up to temperature and the water inside the heater is near boiling? Thanks so much
Hi, Yes, it is water from the tub that goes to the solar heater and it makes its way back to the tub. The water is treated with bromine and PH reducer so it has to stay be the same water for the chemical treatment to be right. To control the temperature of the tub, i use a thermostat switch that turns off the solar heater circulating pump when the set temperature is reached.
@@marc5183 thanks for your reply, so say if the hot tub is up to temperature what happens to the water that is still heating up ( close to boiling) thats already in the solar heater?
@@mykey_91 When the water in the solar heater is not used and it's still sunny, it gets very hot. The temperature sensor says that its 230F. Eventually the sun goes down and it cools fast. Those solar panels are design to be able to stand hot temperatures, it's all metal and glass.
Thanks Marc, that makes sense. As I will be using PVC tubing in the collector I will set it to circulate if the hot tub exceeds the temperature I set or the PVC may melt! Have you had any issues using copper pipe affecting the chlorine/bromine ? I read somewhere that this can happen. Thanks for your help!
Ouch, PVC has a melting point of 160F. The water in my solar panel easily reaches 200F regularly when it sits in the sun when there is no demand for hot water. Fortunately, it can handle it as long as no pressure builds up within the panel. With PVC you have an additional problem: the water in the panel can't be over 160F. I don't know how you can do that. I would advice to Craigslist a copper made water heater panel. I paid mine $100 and it was cheaper than making one out of PVC. I just had to open it, clean it, make sure it was sound and caulk it back together. Plus the professional made ones are way more efficient and look better in your yard. As far as chemistry I was concerned at first. I use bromine and after over a year of use, no problem.
Sorry Dave, just saw your question now. Sure, the pump is a Surflo 8000-443-136, they might have update the model by now, you don't have to buy the exact one. It just has to me one with low flow, good pressure and one that does not get damaged if it runs dry. For the switches, just go to E-bay and paste in the search box: Digital Temperature Controller Thermostat ITC-1000 12V Fan Heater Control Cooler
Hi Mike, Here the eBay link for a 115 volts switch. If you don't have 115volts available, they make the same switch for 12volts. You can use a battery and the solar panel to keep the battery charged. m.ebay.com/itm/AC-110V-F-Temperature-Temp-Controller-Incubation-thermostat-Sensor-Switch-Relay/381405974371?epid=601727960&hash=item58cd914f63:g:miAAAOSwVL1V
Hi Marc, I went for a built panel in the end and it’s all running well, have you had any issues with chlorine/bromine in the copper pipes? Also, is it all still working well or have you changed anything?Barry
Hi Barry, I opted for the bromine treatment for that very reason. I heard chlorine and copper don't do well. I haven't had any issues with bromine, no discoloration on the water, no smells. I have not changed anything to it. I just had to replace the thermostat probe, they are the weak link, but they are cheap to buy. I enjoy my tub a lot especially after surfing or a motorcycle ride. The only bad thing is in the winter it often doesn't reach temperature. It needs to be full sun to keep it hot.
Hi Marc, I have a 800L home made wood fired hot tub, want to add solar to top up/maintain heat, how long will it take?! I'm going for the copper coil option (also on TH-cam) no need for thermal cut outs etc as I'm in England.... I can take the lid off!
Hi Toby, Let’s take a look at my experience first. I live in Northern California where I get fog a lot. When that happens, I get no hot water at all. I has to be sunny. On a bright warm sunny day(best scenario here), the hot tub water goes up 30 degrees Fahrenheit in one day. My hot tub is 110 gallons(half the size yours is) and I have a 10 feet X 4 feet solar panel. During the summer I can maintain the temperature very easily. My hot tub lid is very old and doesn’t do a good job keeping the temperature in, however, I isolated the heck out of the tub itself with expendable foam and fiberglass. It drops about 8 to 10 degrees Fahrenheit overnight, but it is easily made up during the day. Since solar is free I haven’t replaced my crappy lid yet (it is on my list of things to do). In your situation, you got twice the volume of water, so it’ll take you probably 3 sunny days to get the water to 105 degrees Fahrenheit, but once it is there and you have good insulation and a good lid, you will able to maintain the temp with a 4x10 panel. If i were you, i would install 2 panels for extra boost. Let’s say you get 3 cloudy days in a row, now your tub is at 80. It will take you 2 sunny days to get back to 105. Plus you probably won’t be able to use your tub in the winter when the sun is lower in the sky. So a 4X10 panel will work, but not super good. Use more panels and insulate as much as you can. I hope this helps. Have fun with your project.
I just got a hose rated for high temperatures. Bought it at Home Depot in the garden hose section. I don't remember the brand, but it says on the label it can go to 160 degrees F. I've had no issues with it so far.
![เขามัทรี - เอ็กซ์ ศุภกฤต - จอนนี่มิวสิค [ Official MV ]](http://i.ytimg.com/vi/AS9ufKuQIVs/mqdefault.jpg)
Excellent video and excellent set-up! Thanks for sharing! This is the best set-up I've seen so far. I love that you didn't use a submersible pump, and your temperature controls protect the hot tub. I wish I could find instructions to build this sort of thing. I'm savvy enough to set things up, but not quite savvy enough to be able to figure out the equipment I would need.
Thank you Brandon for the compliments.
Let me know if you want to build it, we can get in touch, I can send you a diagram and help you over the phone. The hot tube has been a blessing for me, best thing I've done in my backyard.
Thanks Marc, appreciate the info, glad it’s all still running well, I only use bromine in my tub so that’s good to know. I set mine up last month (Spain) and found that whilst it will maintain a temperature it won’t increase it unless it’s a hot full sun day, pretty sure it will work well from April though.Now looking at doing something similar for our domestic hot water. Thanks again for the reply.
Barry
I hear what you are saying Marc but if I set the sensor in the panel to switch on the pump around 130f and the sensor in the hot tub to switch on the pump to circulate water when over 98f that should prevent overheating the pvc, the issue would be if water is left to boil in the panel. I'm also looking at the possibility of using a 12v valve to allow the water to be 'dumped' via gravity into the hot tub when the set panel temperature is reached, this way you get all the hot water from the panel instead of using cooler water from the tub to push the hot water from the panel, just a thought at the moment. Thanks for your help, it's appreciated.
I use a 12v 20 dollar hot water recirculating pump on its 3rd year that runs direct drive from panel no thermostat. Adjusting water panel to semi regulate temperature. Non stop for the 3 years.
wow, non stop for 3 years, that's amazing for a $20 pump. Of course if you used a thermostat you would be able to exactly dial the tub temperature that you want without having to adjust your panel. Over the top water temperatures in your tub might harm plastic parts and lead to premature components failure.
I like it. I'm trying to figure out if I should couple my collectors and thermal heat exchanger into the electric system. I do like the independent system idea too.
Going to the grid is more ambitious than an independent system.I would go through a solar panel contractor for that. Best of luck.
Marc, 2 quick questions:
1. When the thermostat hits the low set temp and switches the pump off what stops the water in the collector flowing back into the hot tub?
2. I like the concept of monitoring the water temp in the hot tub to ensure it doesn't get too hot, but I can't figure out how you have it wired to isolate the pump when you have the pump connected to the other thermostatic switch?
Sorry if that sounds like 2 stupid questions but I really like the idea of the pump only circulating the water when it's hot enough, it has to be better that constant circulation and want to get it right first time.Barry
I can't figure out how to send you a diagram on this, but I will try to explain in words.
For your first question, I added a check valve about 3 feet after the pump outlet. It's a 1/2" brass check valve from home depot. Make sure it has the teflon inside because it makes a better seal. It does a good job keeping the water in the panel despite the gravity of the hill.
For your second question, both of the switches are wired in series. So the wire goes from the 120W solar panel to the first switch to the second switch to the pump and back to the 120w solar panel. Both switches have to be closed at the same time for the pump to turn on. If not at least one of the switch will be open and no current will get to the pump. In this case the water in the panel has to be at least 140 degrees and the water in the tub has to be below 106 degrees. If one of those 2 conditions is not met, the pump will not turn on.
I got my first hot tub about 4 years ago it is just as a portable inflatable hot tub or a kiddie pool on steroids but I really like it I have considered doing this that you would probably damaged my tub being inflatable vinyl that looks like a fun project
It was a fun project and still working well. It's not going to damage your tub unless you let it get too hot. I have my thermostat switch that cuts the system when the tub reaches 106F.
Great video thanks, in this setup does the solar heater take the water from the tub to reheat? Or is it connected to fresh water supply? If so how do you deal with overflow? Also what happens if the tub is up to temperature and the water inside the heater is near boiling?
Thanks so much
I am going to build, so look forward to your help
Hi,
Yes, it is water from the tub that goes to the solar heater and it makes its way back to the tub. The water is treated with bromine and PH reducer so it has to stay be the same water for the chemical treatment to be right. To control the temperature of the tub, i use a thermostat switch that turns off the solar heater circulating pump when the set temperature is reached.
@@marc5183 thanks for your reply, so say if the hot tub is up to temperature what happens to the water that is still heating up ( close to boiling) thats already in the solar heater?
@@mykey_91
When the water in the solar heater is not used and it's still sunny, it gets very hot. The temperature sensor says that its 230F. Eventually the sun goes down and it cools fast. Those solar panels are design to be able to stand hot temperatures, it's all metal and glass.
Thanks Marc, that makes sense. As I will be using PVC tubing in the collector I will set it to circulate if the hot tub exceeds the temperature I set or the PVC may melt! Have you had any issues using copper pipe affecting the chlorine/bromine ? I read somewhere that this can happen. Thanks for your help!
Ouch, PVC has a melting point of 160F. The water in my solar panel easily reaches 200F regularly when it sits in the sun when there is no demand for hot water. Fortunately, it can handle it as long as no pressure builds up within the panel. With PVC you have an additional problem: the water in the panel can't be over 160F. I don't know how you can do that. I would advice to Craigslist a copper made water heater panel. I paid mine $100 and it was cheaper than making one out of PVC. I just had to open it, clean it, make sure it was sound and caulk it back together. Plus the professional made ones are way more efficient and look better in your yard.
As far as chemistry I was concerned at first. I use bromine and after over a year of use, no problem.
Thanks Marc.
Gday
Very helpful vid
How and where have you placed the temperater sensor in the solar heater panels ?
I used aluminum tape and taped it on the top part of the solar water heater panel, on the inside, against the copper pipe.
@@marc5183 Thank you
Hi Marc, can you tell the model numbers of both motor and thermal controllers so I can buy them. Thanks for great system!
Sorry Dave, just saw your question now. Sure, the pump is a Surflo 8000-443-136, they might have update the model by now, you don't have to buy the exact one. It just has to me one with low flow, good pressure and one that does not get damaged if it runs dry.
For the switches, just go to E-bay and paste in the search box: Digital Temperature Controller Thermostat ITC-1000 12V Fan Heater Control Cooler
Marc,
What are the controllers you got and where did get them. Could you provide a link?
Thanks Mike
Hi Mike,
Here the eBay link for a 115 volts switch. If you don't have 115volts available, they make the same switch for 12volts. You can use a battery and the solar panel to keep the battery charged.
m.ebay.com/itm/AC-110V-F-Temperature-Temp-Controller-Incubation-thermostat-Sensor-Switch-Relay/381405974371?epid=601727960&hash=item58cd914f63:g:miAAAOSwVL1V
Hi Marc, I went for a built panel in the end and it’s all running well, have you had any issues with chlorine/bromine in the copper pipes? Also, is it all still working well or have you changed anything?Barry
Hi Barry,
I opted for the bromine treatment for that very reason. I heard chlorine and copper don't do well. I haven't had any issues with bromine, no discoloration on the water, no smells.
I have not changed anything to it. I just had to replace the thermostat probe, they are the weak link, but they are cheap to buy. I enjoy my tub a lot especially after surfing or a motorcycle ride. The only bad thing is in the winter it often doesn't reach temperature. It needs to be full sun to keep it hot.
Nice set up-you must be a German engineer!
😂 Lol! Thank you.
I'm actually French.
Hi Marc, I have a 800L home made wood fired hot tub, want to add solar to top up/maintain heat, how long will it take?! I'm going for the copper coil option (also on TH-cam) no need for thermal cut outs etc as I'm in England.... I can take the lid off!
Hi Toby,
Let’s take a look at my experience first. I live in Northern California where I get fog a lot. When that happens, I get no hot water at all. I has to be sunny. On a bright warm sunny day(best scenario here), the hot tub water goes up 30 degrees Fahrenheit in one day. My hot tub is 110 gallons(half the size yours is) and I have a 10 feet X 4 feet solar panel. During the summer I can maintain the temperature very easily. My hot tub lid is very old and doesn’t do a good job keeping the temperature in, however, I isolated the heck out of the tub itself with expendable foam and fiberglass. It drops about 8 to 10 degrees Fahrenheit overnight, but it is easily made up during the day. Since solar is free I haven’t replaced my crappy lid yet (it is on my list of things to do). In your situation, you got twice the volume of water, so it’ll take you probably 3 sunny days to get the water to 105 degrees Fahrenheit, but once it is there and you have good insulation and a good lid, you will able to maintain the temp with a 4x10 panel. If i were you, i would install 2 panels for extra boost. Let’s say you get 3 cloudy days in a row, now your tub is at 80. It will take you 2 sunny days to get back to 105. Plus you probably won’t be able to use your tub in the winter when the sun is lower in the sky. So a 4X10 panel will work, but not super good. Use more panels and insulate as much as you can. I hope this helps. Have fun with your project.
Is that garden hose you used?
Thx
I just got a hose rated for high temperatures. Bought it at Home Depot in the garden hose section. I don't remember the brand, but it says on the label it can go to 160 degrees F. I've had no issues with it so far.