solar inground plumbing help - see pics

[cml0904]

Hi, need help with plumbing for FAFCO solar panels. pool is circulating but no water is filling panels, well maybe a little. Return is dripping (hubby said he knows what he did wrong and will fix tomorrow), but that return line that's dripping is NOT hot. Panels are supposed to be 18lbs empty and 65 lbs full. obvious they're not heavy or full of water. Please see pics and let us know what we did wrong or what we should do to correct.

we plan to build a rack next weekend, but for now wanted to make sure all was working, which it's not!

thanks for any help.

[inetdog]

Hi, need help with plumbing for FAFCO solar panels. pool is circulating but no water is filling panels, well maybe a little. Return is dripping (hubby said he knows what he did wrong and will fix tomorrow), but that return line that's dripping is NOT hot. Panels are supposed to be 18lbs empty and 65 lbs full. obvious they're not heavy or full of water. Please see pics and let us know what we did wrong or what we should do to correct.

we plan to build a rack next weekend, but for now wanted to make sure all was working, which it's not!

thanks for any help.

A couple of things come to mind immediately:

1. That wide open bypass pipe running horizontally between supply and return is not going to allow much pressure to drive water through the loop.
2. You probably do not have an air bleed mechanism in place, so you will need to be able to pull suction on the return or put pressure on the supply or both to get water into the panels at all, especially if it is uphill to them.

My advice: Start by putting a valve on the bypass line. Or put in a full diverter valve system. For maintenance on the panels, you will also need two valves one in supply and one in return instead of the one you have now. That will allow you to work on the panels while your pump and filter are running.

PS: I hope that is what hubby thinks he did wrong.

[cml0904]

Haha, looking at it again it looks pretty obvious and common sense no-no. He's adding a valve now. We will get an automatic controller too. Thanks for the help.
I'll update later on. thanks!

[skeeter_ca]

I concur with inetdog, with no valve in that bypass pipe the pressure is just bypassing the panels because there is less restriction through the bypass pipe than through the panels. Place a ball valve or a 3-way valve in the pipe and it will reroute the water to the panels.

Also the way the panels are laying on the ground it looks like you could easily get a lot of trapped air in your panels. I would recommend a rack to tilt the far side up and don't forget to angle them slightly so the air can purge out of all the panels. See example below.

Mod note - ad deleted for second time -
skeeter

[cml0904]

oh wow, thanks, in all the things we've read, i've never heard anything about the tilt. That's a great graphic that explains everything so well. That's good to know!! Our pool stays at about 79 degrees usually. We have a solar blanket we use, but it will be interesting how well this will work. Will update. thanks guys!

[cml0904]

solar for dummies

Well, it's been rainy in Atlanta and finally should be sunny as of today. I have one more pic to show the angle of the panels. As I was looking at the graphic for the tilt and plumbing, i worry we still have it wrong. I hear some gurgling and assume it's because the plumbing, slope, angle, or all of it is not optimal or even right.

Please be blunt and tell me how we should set it up for our particular area. We can redo now easily, later, not so much! So glad we didn't build a rack yet.

My questions are then, about plumbing (should we have configured everything different?) and please explain for dummies how to angle both the ground for now and then the rack (rack both angle and pitch).

Probably would be a good idea to call a local Fafco dealer to get his input after we think it's as good as it'll get.

Oh, the panels face the house in a Southeastern direction. We could turn them more towards the south but the water flow, angles and tilt are confusing.

Thanks for any help. Remember, be blunt! If we've done this all wrong, that's ok to say, I only want the most optimal setup and want to be done!
20130609_103225slope.jpg

[skeeter_ca]

To me it looks like the headers(the big pipes at the top and bottom of the panel) are pointing up hill. The best orientation would to have the headers at the top and bottom of the slope in the yard. That way the panels can fill with water from the bottom up and push all the air out of them into the top header and then return back to the pool. A rack could easily remedy the problem. It does not need be tall, just a flat angled toward the sun area slightly larger than the panels with the top higher than the bottom so the panels slope down. The tilt of the panels is done when you put the panels on the rack before the piping is attached to the headers. Just think of all the panels together as one big rectangle. When layed out on the rack make it crooked so the the outlet going back to the pool is higher on the rack the the other end.

Here is a quick pic i whipped up. hope it helps.



skeeter

[inetdog]

Thanks for any help. Remember, be blunt!

Skeeter got it just right.
The bypass pipe let the water go straight from one feed pipe to the other with nothing to push it through the panels.
Now the bottom panel is playing the same role as the bypass pipe. Water can flow from the lowest panel connection on one side to the lowest panel connection on the other side with nothing to cause the water to fill any of the panels.
If the flow and pressure are high enough to force water into the upper panels, you have the problem that this will just compress the trapped air in the upper section instead of pushing the air out through the return line.

What skeeter drew, with the almost horizontal headers, and with the return pipe at the top end of the return header, will force the water to completely fill all of the panels before any of it can get to the return pipes.
And having the supply at one end of the supply header and the return at the opposite end of the return header will make the flow through the six panels closer to equal.

PS: If you supply the water to the high side, it can just trickle through the panels without filling them, and not make good thermal contact with most of the panel surface.

[Naptown]

One last thing
I assume the array is higher than the pool. The automatic valve and controller are good things to have as it makes the operation automatic.
However you need to add a check valve between the filter outlet and the control valve. Without this if the pump shuts down (timer I assume) the water in the collectors will tend to backwash the filter into the pool putting all the stuff it filtered out right back in.

[inetdog]

... the water in the collectors will tend to backwash the filter into the pool putting all the stuff it filtered out right back in.

Out of curiosity, have you ever seen a system do this, or is this just a design observation?

[Naptown]

Out of curiosity, have you ever seen a system do this, or is this just a design observation?

Yes I have.

[russ]

Yes I have.

I'll bet that pool owner was not a happy camper!

[Naptown]

I'll bet that pool owner was not a happy camper!

good thing I was the one to fix it and not the one who forgot the check valve.
Really wasn't a big deal though it got cleaned up the next filter cycle

[cml0904]

Hi, sorry for the late reply. I did read these right away.

I had called Fafco to look at it also, and they suggested the flow was maybe too fast and to partially close the valve to allow more time for the water to warm. The pool is warm and it appears to be helping a lot. 90 degrees today! I'm sure to extend the season, it will need to be setup optimal and we will definitely tilt the whole thing according to the drawing. Thanks so much for that!

If I understand correctly, we should change the location of the return also? We do have a check valve and will install that this weekend, along with another isolation valve and relocate those closer to the filter. Not sure why hubby put it clear down near the panels.

Anyway, please let me know if we should change the location / configuration, as it won't be that big of a deal to do it now that we don't have the rack built yet.

Thanks again everyone!!

[5-7]

can't see pics

Can't see pics without a post #oldthread

---Mod Note: There are better places to make non-contributing posts to get your count up than by bumping an old thread.
Like the "Please introduce yourself" topic.