I thought I would share my recent work with all of you. A little info..bought a house last month, it has a pool and raised spa, but no heating source for either.. I decided to go the solar route to start off.

My dad and I got the my solar system all installed over the past two days. Between all the plumbing, 200 sq ft of FAFCO solar panels (Four 2'x20' panels and two 2'x10' panels) and all the misc. items for all the plumbing and installation etc.. I was able to get it all done for under $700. (got a great deal on panels from and end of year blowout sale).

Now I have heat and it is free from here on out.

Today is the first day I have run it and we have been a bit colder the past few days (upper 60s-low 70s during day and upper 40s to low 50s at night), so my water temp this morning was 62* in the pool and spa. I ran the solar for 3 hours from 9am to Noon recirculating both the pool and spa, and the pool temp rose up to 70*

I wanted to see how well it would heat just the spa so I switched it to the spa only and in less than two hours it has gone from 70* to 90*...outside air temp right now is 74*

We will see what it gets to by 4pm today

I am very happy so far.

It isn't all completely done yet, I have some more clamps to install for all the plumbing running up the wall and the blower for the spa, and some bracing under an small section of the pipes. We plumbed it so that if I decide to get a heater I can hook it right up to my current layout and not have to change anything, so right now it just loops around and needs a little bracing under it for some extra support...which I currently just have a scrap piece of pipe with a T on top if it for temporary support.

here are few pictures of everything we did:







Now we can FINALLY use our pool and spa.. we haven't been able to use it since we moved in being water temps were always around 70* ... but not anymore!

Nice work! And amazing price!!

I have a couple of concerns/comments/questions:

Are the two sets of panels (verticals and horizontals) plumbed in series? This will not only reduce the panel efficiency but it will also increase head loss.

Is the output of one panel feeding the second set of panels from the top? Normally, panels are fed from the bottom to make sure all of the air is removed from the panels when priming. Trapped air can make the panels less efficient.

Do you have a check valve after the filter? Without a check valve, when the panels drain, they may drain backwards through the filter flushing debris into the pump. If you don't have a vacuum release valve, then it may not matter since the panels won't drain but that may cause other issues.

Lastly, is the black pipe on the roof black PVC or ABS DWV or something else?

I didnt look closely at the pics. Mark is right you need to tweak the setup on the roof. But those are easy enough: replumb the bottom of the right vertical panel to the bottom left of the horizontal set. Move the return for the horizontal set to the top right. Finally, run the top right of the vertical panels all the way over to the top right of the horizontals and connect together before returning to the pad. This last step is important to the balance between the arrays.

I'm not sure where to add the vacuum releases? The tough part is that for the best draining hopefully theres a slight pitch to the panels from top right to bottom left for the way I suggested you replumb.

The check valve is easy enough to add.

Nick good job, Mark is correct. Look at my solar install for some tips. Hope this helps

Answers to questions in bold.


I thought the way we did it was fine being water comes in the bottom left panel then forced to the top of those panels and out the top right, then into the top left being forced down through the panels to the bottom right. I guess I'm not seeing where the issue is, since once pressure is in the system the water can only go one way from in to out. If it is plumbed wrong as you are saying though, how should it be plumbed? the way we have the panels is the only way they would fit with the shape of the south facing roof which is where I want them, so no panels can/will be moved.

So far It seems to be working just fine and heating just fine, so I don't want to change anything if I don't HAVE to, but suggestions are appreciated.

Thanks

Ok, I understand now what we did wrong after doing some drawings.

This first picture is how it is now (Red is incomming line from filter, blue is return line to pool):



This picture is how it SHOULD be if we ran all incomming water from the BOTTOM however I am not going to do it this way.



This picture is how we are going to re-do it as it will be easiest and save almost all of my current plumbing..only downside is inputing from the top with the air/prime issue, but I think I should be fine. If I ABSOLUTELY Can't run it this way let me know, but it is much better than what I have I think. Also, I am going to put the vacuum release valve in a "T" where I labeled it in this picture.



Let me know what you think.

Thanks.

Solar panels should be fed from the bottom only and in parallel otherwise you are asking for problems. This is the way I would plumb the panels:

Split the supply line (from filter) in two and then feed both panels from the bottom. Take the top return lines combine them and then have a single return line. This will prevent any issues and give you the maximum heat out of the panels.

Also, since you are replumbing the roof anyway use ONLY PVC pipe. ABS is not rated for pressure nor is it UV resistance so really there is no point using it. Most of the stuff you get from home stores should only be used for drain, waste or vent (DWV). If you want black pipe, either paint it or use black PVC.

where can I get black PVC? The ABS I got because it is the only black pipe I could find and it's pressure rated plenty high enough for the amount of pressure running through it, so instead of running white PVC I went ahead and bought the black ABS. My dad has Black ABS in his system too which has been up for 2 or 3 years now. But if we can find black PVC I will get that.

Thanks for all the help!

I and most pool professionals would never use ABS DWV (drain, waste, vent) pipe for pool plumbing. ABS is rated at less than a third of the pressure of PVC so it can weaken over time. It is not meant for pressure application let alone pool plumbing. Check valves can add significant pressure waves to plumbing so it needs to be able to stand up to water hammer. Plus like I said before, the stuff you get at home stores has no UV protection so it is worse than PVC which at least has some protection. Both really need to be painted either way so you might as well get white PVC and just paint it.

Ok, I will just use white PVC and paint it for the new plumbing then I guess. Easiest would be finding black PVC, but since I haven't seen black PVC anywhere I am not sure where to get it. Any suggestions?

Here is how we will plumb it. Split the supply line and run one line to bottom corner of vertical panels and one to bottom corner of horizontal panels. Then have return line from both converge into 1 line.

Does this look right? the green spot is where I was going to put a T with the vacuum release valve. will it work here or should it be somewhere else?



Again, thanks for all your help!

Yeah that looks like what mas985 said and what I tried to describe - actually a bit cleaner than what I described. That should definitely work!

That setup should work fine. As for black PVC, it is very difficult to find and even if you did, it is probably a lot more money and I don't believe it is 100% UV proof anyway just more resistant. I would stick with white and paint it. It is not hard to spray paint the pipe. Just use a piece of cardboard underneath for over spray.

I am certainly no expert, but have been trying to design my own system. I have seen that ideally you want the return (hot water) lines as short as possible so there is less plumbing to heat before reaching the pool (granted this may be a minor difference).

With that in mind, I would supply the vertical at the bottom left and the horizontal at the bottom right. And then return from the vertical at the upper right and the vertical at the upper left, tie together and run to pool with the vacuum release at your green dot.

This way you could probably reuse all the pipe straps you have on the long horizontal run when you replace with PVC and not add more holes to the roof

HA! Now why did I not think of that! Making the necessary changes now will so simple and no need to plug holes in the roof, drill more holes across the top of the roof etc..

Thanks for your suggestion! Hopefully I get a chance in the next week to get up on the roof and fix everything.