Pressure Side Pool Cleaner Slow


Aug 3, 2019
Northern California
I had a Pentair 1 HP booster pump which failed this past summer. It was replaced with a Polaris PB4SQ booster pump. It is energy efficient and works with low flow VS filter pumps. When this new booster pump is on, my VS filter pump is running at 1k RPM. Now, my 15 year old Lethro Legend II pool sweep is running slow and gets stuck a lot. There just doesn't seem to have enough pressure going to it to move it around like it used to. Not sure if it is due to the new booster pump. Or could it be the hose assembly because I do see water coming out from one of the screws on the backup valve, but nothing on the hose and fittings. Also, sometimes the pool sweep moves around tilted on one side so it doesn't pick up the debris. Is it time to replace the pool sweep? Or should I replace the hose assembly first?


Gold Supporter
TFP Guide
Jul 21, 2013
Northern NJ
Rebuild or replace the Lethro. The cleaners build up friction in the bearings and gears over time that slow them down.

I think this is the best pressure cleaner...

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