Hayward 1.5hp Pump
Hayward Sand Filter Model S166T
When I begin filtering I usually backwash for a minute or so and then rinse for about the same amount of time. Usually till the little glass connected to the side of the filter runs clean. When I switch to the filter setting and run the pump everything runs great. The gauge shows about 17psi and the return in the pool is pumping water back in the pool strong. After about 10 minutes or so the return pressure back into the pool gets very weak, but the gauge still has a good psi reading. If I repeat the backwash/rinse it will go back to normal though. I don't think that's the way it works though. Any insight would be appreciated.