We run the pump in the morning for 2 hours at 2850 rpms. Then again for 3 hours in the afternoon at 2200 rpms. The pool sweep runs for one hour also at the afternoon run. This was the instructions from our installer. Both seem way to loud.
Here are some possibilities:
1) Cavitation. Excessive suction due to speeds too fast for the suction plumbing to feed the pump.
2) Cavitation due to clogged lines or valves closed. To check for cavitation, get a vacuum gauge and install it in the front drain plug.
3) Bad bearings.
4) Fan whine. At high speeds, the back mounted fan can get a little noisy. To check, cover back fan cover to see if sound changes. Only block for a few seconds. Don't use anything that can get sucked into the fan.
5) Rocks in the impeller. Check pump basket for small rocks.