I have an about a 15k gallon pool. Someone previous eliminated the drain. There are no valves, only one 1.5 inch suction line from the skimmer (about 40 feet), a Hayward standard 80 cartridge filter and a 1.5 inch return line that leads in some fashion to 3 return outlets. This is in Florida, year round.
The pump is a 1 Hp Pentair Whisper Flo (plumbing reduced from 2 inch to 1.5 inch). Motor, seals, bearings, impeller all replaced as well as any air bubbles eliminated coming into the suction line. The pump starts out quiet prior into the basket filling with water. Once water in the basket and pressure builds it starts making a loud noise. (the noise existed before the replacements).
When I plugged up 2 return lines at pool, I would hear the pump quite down significantly.
Any idea's to decrease this loud noise? Is the pump too large? What is going on with this strange pool?
Thanks to all for your recommendations.