Pump requirements for Solar Panel Installation

[John Pacino]

Hi, i purchased two 2x20 SunQuest solar panels last year which i connected and laid them against a west/south/west facing fence. While it heated OK, i was not getting the full value of the solar panels. I would like to move the panels to my Southwest facing roof that gets sun exposure from 10a - 6p that should definitely help with heating our pool (located in CT)

The pool was recently installed a few year ago and at the time did not contemplate solar roof panels. I'm currently operating a 1HP Hayward Power-FLO Matrix pump with a Hayward Perflex Extended Cycle DE Filter. The filter is rated for 50 GPM and 50 PSI. 

To get the water up to the pool, i would need to run about 50 feet of PVC to the house and then up 2 stories, an additional 30 feet, and back to the pump area. I've read in multiple threads that a 1HP pump should get the water up to the second story but am hoping to confirm with my configuration. I could upgrade the pump to a hayward 1.5HP without changing the filter if needed.

I've already installed a 3-way jandy valve that I used last year when the panels were against the fence (about 5 ft away). The plan was to run PVC above ground to the house (along side the pool and deck) and up to the roof with at least 1 check valve to make sure the back pressure does impact the pump. 

Thank you in advance for your feedback. 

Best,

John

 

[RDspaguy]

Hi john. I could take an hour or so to look up the specs, compute the head and do the math, but as the only difference will be the pump, why not try it and see if it works with what you have? You can always upgrade the pump later if needed.

[John Pacino]

Thanks @RDspaguy. Sounds like a plan. Would you make any other recommendations before we start putting down the pipes? Is 1 check valve going up the house enough? Or should I install two? I've heard to avoid T pipes and to use 45 degree elbows whenever possible. 

[RDspaguy]

No on the 45s, they create nearly as much head as a 90 for half the bend. Use what works with the fewest fittings.

If your panel has a release valve to allow air in so the panel drains when the valves are bypassing it, a check valve on the return side will replace a second jandy valve, otherwise it is not needed.

 

[John Pacino]

Ok, there is no release valve in the panels so will not add the check valve either. To summarize, 

Fewest fittings, no added check valves and let's see if the Matrix can do the job, otherwise, we'll upgrade. 

Thanks. Will let you know how it turns out. 

[John Pacino]

@RDspaguy - one more question, if all the existing plumbing is 1 1/2 PVC, i should continue with that for the solar panels as well, right?

[RDspaguy]

What size are the panels? I would run that size to the panels on a bypass. You can give it full force to prime the panels, then open the bypass halfway or so and still get good flow to the panels and pool.

[John Pacino]

The Panels are 2x20 with 1 1/2 threaded coupling. 

[RDspaguy]

Then 1 or 1.5. Inch pipe. 

[John Pacino]

Ok - thanks!

[John Pacino]

So far, so good with the FLO Matrix. I've ran all the plumbing from the pump to the top of the house using 1 1/4 inch pipe. After letting all the fittings cure for 24 hours, i turned it on, diverted the water to the roof and video below shows the flow i'm getting 25ft in the air. The PSI remained around 10 which is what I run with a clean filter. Based on the results so far, i'm optimistic that the water will be able to make the bend around the roof and to the panels just a few feet away. We're installing the panels on the roof this Friday and will provide an update. 

Thanks for the advice so far. 

Feeling optimistic, 

John

[RDspaguy]

Getting it going is the hard part. Once it is primed it takes very little to keep it flowing.

[John Pacino]

@RDspaguy - good news, bad news. Everything is hook up and when the valve is turned 100% to the roof, everything appears good. The PSI hovers around 12 and the pressure coming back to the pool is decent. 

unfortunately, when the valve is 100% off to the roof, the PSI is dropping to 1 and I lose prime. I added a check valve about 6 inches from the T of the return which has helped but still struggling. When I turn the valve coming out of the filter about 75% open, it helps and the PSI jumps to about 4. 
 

what do you think? I’m surprised that my issue is when the roof is off. 

[RDspaguy]

I am not sure I understand. Where are you measuring psi, at the filter pressure gauge? When the psi is 0 do you have flow? Loosing prime at the pump or in the panels? Where exactly is the check valve?

[John Pacino]

The PSI is being measured by the filter gauge. When the PSI drops to 0-1 there is fairly decent flow still but the pump basket never fills up fully with water and the pump is louder than normal. See attached. 

The check valve is in the return from the roof right before the T that merges the return directly from the filter. 

[John Pacino]

@RDspaguy - good news. I went out there this morning to check a few things and found something lodged right before the shut off valve going into the pump which was preventing the pump to pull full water. Took that out and everything is working great! 8PSI when sending directly to the pool and 12PSI when sending it up to the roof heater. Getting better flow when going directly to the pool but the return from the roofs is pretty good to circulate the water. Not sure if I needed the check valve or not as the piece of plastic i found was probably lodged before adding it but it doesn't seem to be hurting anything. 

Thank you for all your advice and help but it appears we're good to go. Proud of my FloMatrix 1.0HP to push the water up to the roof when others said it wouldn't work. 

- John

[RDspaguy]

Awesome John! I was as confused as you about the situation. Glad you got it figured out.👍