My pressure gauge never goes above 20psi. Right after a backwash it's 16psi. The filter can be totally clogged and very little water coming out of the return and the pressure still reads 19-20psi. I replaced the 150lbs of sand this spring with fresh pool sand.
I just backwashed the filter then put my hand over the return to block it to try to increase pressure. Pressure went to 20psi and I hear a sound from inside the filter itself, like water being pressed through a small opening.
Could I have a problem with the filter itself or should I try another pressure gauge?