Pump Pressure

[Watermom]

Yes, and also cheap to replace.

[catnip]

You might try a quick temporary fix for your sticking gauge (worked for me at least). Unscrew it and give the inlet fitting a good rap on something solid. In my case it dislodged some rust and moisture and the gauge went down to zero; this "might" get you by until you can get a replacement.

BTW, I just looked on Grainger's web site and you can get an all stainless (all metal parts) liquid-filled 2.5", 60 psi gauge for $25.25 plus shipping. The cheap ones (10 bucks) from the pool store seem to last about a year before suffering from corrosion. I'm about to order one to see how long it holds up.

You might also look up the pump curve for your pump on the manufacturer's web site (some e-tailers also post the curves) and see what kind of flow you should be getting with the pressure you are showing. You will need to calculate the total dynamic head (TDH) in feet as input to the pump curve which consists of the pressure head which is the pressure in psi you are seeing on your filter gauge X 2.31 (ignoring the pressure loss from the pump to the filter) plus the suction head from the drains/skimmers to the pump which you can guesstimate as 5-10 feet, i.e.

TDH = (Filter Pressure x 2.31) + Estimated Suction Head

For your clean filter pressure of 26 psi and estimating 8 feet of suction head that would equate to:

TDH = (26 x 2.31) + 8 = 68 ft.

At 30 psi the TDH is 77 ft. This is a pretty high head for most pumps but not unmanageable for some. In any case with 1.5 inch return plumbing you want to keep the flow under 63 GPM which is based upon a maximum flow rate of 10 feet per second. However, the Hayward spec on the S200 filter shows a design flow rate of 44 GPM, so you really want to stay around or slightly below that rate. My guess is that your pump is over-sized for your filter and 1.5" plumbing and is attempting to push too much water which results in the higher pressures you are seeing. If this is true, you could save money on electricity and have a more "efficient/balanced" overall system with a smaller pump (3/4 or perhaps even 1/2 HP full rated).

Here is a link to pump/filter sizing guide on Hayward's site:
http://www.haywardnet.com/pdfs/Pump_filter_sizing.pdf