Plumbing questions: solar return to spa

[chumbley]

I'm in the final stages of design for my total pool/spa equipment replacement. Some background:

- Pool with spillover spa, about 25K gallons total
- 2 skimmers in pool (1.5")
- 1 drain in pool (1.5")
- 1 drain in spa (2")
- 2 pool returns (1.5")
- 5 spa returns (2")
- 1 cleaner line (1.5")

I am using Intelliflo VS pump, EasyTouch automation, Pentair SWG. I plan to use a suction side cleaner (The Pool Cleaner). I am adding solar (5 - 4x12 panels). I have an existing H250 heater that I will use.

I have been thinking about returning water from the solar panels to the spa to keep it warmer, and heat the pool with whatever water spills over. Has anyone done this? Where would it be best to plump into the spa return, in the make-up path or main path?

Thanks!

 

[jblizzle]

Seemed like kind of an interesting idea, but since I don't know what the make-up path vs main path I did not comment earlier ... assumed someone else would.

Do you currently have all your flow return to the spa and spill into the pool? That seems like the only way this would work. Unless you are talking about diverting some of the water to solar and then tying it back into the spa (after valves) for all the solar return. But then you would loose the ability to solar heat the pool is you changed your mind.

 

[chumbley]

Thanks Jason. I was thinking that not all of the pump output would be sent to the solar panels. Perhaps it would. Probably depends on the flow rate at the time. Certainly at full output I would expect the flow rate to be higher than desired for the panels.

 

[jblizzle]

The solar heating efficiency actually goes up with flow rate to point. I think you want about 1 gpm for every 10 sqft of panels roughly. Check for your specific panels.

I just am not clear how you would only return part of your flow ( from solar ) to the doable with the rest of the water to the pool and still be flexible for other options.

 

[mas985]

If you plumb the solar return before the pool/spa return 3-way valve, you can choose where to return the water. This is how most pool/spas, including mine, are setup.

If you put the controller into spillover mode, you have hot water going into the spa spilling over into the pool. Or you can set the controller to pool mode and just heat the pool. Or you can set the controller to spa mode and just heat the spa.

 

[chumbley]

Makes sense! Thanks Mark.