Saluda de Nicaragua!
I will be building a new pool, starting in January, 2014. I'm now in the process of figuring out the mechanics of the pool, pump, filter system and the layout of the suction lines and return lines. This is my first time doing anything like this. I am essentially acting as the general contractor for this project. The pool will be about 51,000 gallons in size, rectangular in shape, 60' long by 20' wide, with the deep end making up 17' of the total length and being about nine feet deep. The rest of the pool will be about four feet deep. There will also be an attached jacuzzi/spa with either four or six jets which will drain into the main pool. I have decided to not have a main drain but will instead have three skimmers, each with its own run back to the pump and each with its own valve. I will have seven return lines, two in the deep end pointing towards the opposite end of the pool where the skimmers will be located, one in the jacuzzi/spa (in case the jets are not turned on), the others located in the four foot deep area. The total surface area is about 1200 square feet. At this point, I am looking at using a variable speed 3HP Pentair Intelliflo pump which is capable of 160 GPM. The filter will be a Pentair Clean and Clear 520 square foot cartridge filter, which can handle up to 150 GPM. For an eight hour turnover, I would be looking at around a 106 GPM flow. For a six hour turnover, I would be looking at around a 141 GPM. I will have a dedicated, valved, suction line to run an automatic pool cleaner. The pool will be an in ground, reinforced concrete, "salt water" pool. There will be no pool heater. This pool will be used mostly by the kids that live in and around us, up to four hours a day, four to five days a week.
In my perusing of different pool sites, pool pump charts and water flow charts in relation to pipe diameters, it looks as if larger pipes are always better, as the pumps don't need to work as hard when either pulling and/or pushing water. If that is the case, why don't more people go to 2 1/2" or even 3" suction and return lines? Generally you get more GPM with less TDH meaning less electricity used. I'm willing to spend the extra $$$ to upsize to larger water lines and lower the TDH as this seems to be worth the cost. Here in Nicaragua, I have paid as much as 44 cents (U.S.) per kilowatt for our electrical power. The more power we use each month, the more we pay. We have the most expensive electricity in Central America. Lucky us! So, keeping our power consumption down with this pool is quite important to us.
1) With the jacuzzi/spa do you think that I can run six jets in there while the pump is also pulling water from the three skimmers and returning that water to the pool? How about four jets instead of six as another option?
2) Do you think I should use four skimmers instead of three skimmers?
3) The Pentair Intelliflo pump has 2" inlet and outlet openings. If I go with larger diameter pipe, say 3", should I be looking for a pump that offers larger diameter openings?
4) What are the ramifications of running 3" lines from the skimmers to the pump and then having to downsize to 2" just before entering the pump? Do skimmers even exist that have 3" connectors?
5) Return lines - 3" lines, downsizing to 1" at the pool wall? What are the ramifications of coming out of the pump with a two inch line and then upsizing to three inches shortly thereafter?
6) If I run a return line off of the main pump for the jacuzzi/spa for the six or four jets, what size pipe should that be so that I get enough pressure for the jets?
That's probably enough to start with. Thank you in advance for any insight anyone can share.