Hi,

I am trying to figure out if it makes sense to replace the motor/pump on our pool to save electricity. It seems to run smoothly (but is a tad louder than I like).

Can someone please help me make sense of this ?

According to the plate the pump is a Hayward Super pump, 1.0 HP, HS-125-JS using 6.0 amp (110 V), made in 1987 (year decoded per "The Ultimate Pool Guide"). The filter is a 27 inch / 70 GPM sand filter with 3.5 sq m.

It is a fairly basic 32x16' 22000 gallon vinyl pool - 1 main drain, 2 skimmers, 2 returns. I want a 10 hour turnover, which means 36.7 gpm (let's say it is 40 gpm).

The pump is 6 ft from one skimmer, so I have about 10+30+30 feet of pipe on the suction side (2 skimmers + main drain)

The discharge side is about 60 ft total.

According to my book 1 1/2" PVC pipe has 8.9 feet of head per 100 ft length at 40 gpm, so that adds up to 11.6 ft of head.

The filter adds about 7 ft of head, 5 for skimmers and main drain, and, say, 3 for the chlorinator

This would be under 27 ft of head. Can this be ? (in the visible plumbing there are 7 elbows which are supposedly equivalent to 7.5 ft of straight pipe each, adding another 4.4 ft of head. There is also a T-shaped valve that adds say another foot of head So we may end up at 33 ft of head total.

If I chose, say a 1/2 HP Hayward Northstar SP4005NS, I could get 70 gpm of flow. Since it is a .37kw, this would be a 3.36 amp motor ?

If the motor runs 10 hours a day I could save 2.9 KWh per day (at about 15 cents per KWh on Long Island, NY) - $13 a month, or $65 per 5 month season.

BTW the previous owners also had 2 returns integrated on the stairs but these two were disconnected behind the filter, probably because of a leak in that line a long time ago (I am guessing)

Can someone help me wit a sanity check on this ?

Thanks a lot

Patrick