I don't close my pool in winter. Just had the pump running 2 hrs a day. It's typically shown about 20psi (down near 15 right after I cleaned the grids last spring). Yes, I had seen it climbing lately but thought it was just algae. The SWG isn't on yet but the water temp was approaching 60 and I had a minor algae bloom, which I took care of with bleach. Thinking it was primarily dead algae, I expected a return to normal with the cleaning. I changed intake valve settings but saw no noticeable change in pressure. Even when all 3 suction sources were open, the pump seemed to be "gulping" water instead of smooth, steady suction.

Carl, can you elaborate on, "At what point of a disconnection does the pressure drop?" I didn't think to change return settings (to pool or to spa) to look for effect.

It happens that I'm about to buy a new gauge to go on a bigger filter I will soon install so I'll try it on the old filter first. I'll pick that up today.

Does anyone out there have any idea whether scale on a salt cell would raise pressures significantly??

Thanks, everyone
Hal