help with dual speed pump and pressure

Jun 14, 2012
Hi guys,

I have a 20x40 IGP vinly pool finishing completion. I have the hayward dual speed super pump along with a DE filter. When the pump is in high speed my pressure is currently at 10 (just backwashed a day ago because of dirt in pool after rain and testing the backwash feature). When I switch the pump to low speed the pressure reading drops to 0 but water is still going through the filter as I can see debris moving in the pump strainer basket, skimmers as well as feel it coming out of the returns in the pool, although at a lower rate than when on high speed. My question is, should the pressure reading on the filter be at 0 when I switch the pump to low speed? The whole system has only been running for a week.


LifeTime Supporter
Platinum Supporter
TFP Expert
May 7, 2007
Silver Spring, MD
You are fine. Technically, the pressure shouldn't be zero. However that is not unexpected and actually fairly common. The inexpensive pressure gauges used on pool filters are not very good at measuring low pressures. The actual pressure is probably 1 or 2 psi, but the gauge simply can't read pressures that low.
Jun 14, 2012
Wow, thanks for the fast repsonse. Would you recommend replacing the pressure gauage with one that is more accurate or call it close enough and be done with it?


Well-known member
May 11, 2009
Youngsville NC
Leave it well enough alone. If you get a guage accurate enough to read the low pressure, it probably couldn't handle the high speed / high pressure readings. As long as you can see water flowing I wouldn't worry about it.
Jun 14, 2012
when the pump is on it seems like the water in the skimmer closet to the pump (shallow end) is swirling more than the skimmer furthest from the pump (deep end). Is this to be expected since one is further from the pump?


LifeTime Supporter
Bronze Supporter
Sep 14, 2007
Central NJ
Yes, assuming 'one is farther' by more than a foot or two.

If the skimmers are plumbed on separate 'home runs' back to your equipment pad, you can adjust the valves so that the flow is somewhat reduced on the closest skimmer so that its to equal the wide-open farthest skimmer.


Well-known member
May 5, 2011
South of Boston
on my pressure gauge, the needle rest is 1 psi, not zero. on low speed it hovers just above it, giving me a reading of 1.5 psi. mistakenly before i was thinking it was 0.5 psi