I read the post "determining pump run time," which recommends 8 hours of run time if your pump is capable of running on lower speeds. I have a variable speed pump that goes from 800 rpm to over 3000 rpm, as follows:
800 rpm 105 W 10 gpm
1200 rpm 175 W 25 gpm
1600 rpm 315 W 60 gpm
2050 rpm 490 W 80 gpm
3000 rpm 1700 W
where gpm is gallons per minute.
Right now I'm running 18 hours at 1200 rpm and 6 hours at 1600, and everything is fine, but I think I'm overdoing it. On the other hand, I suspect that 8 hours at the lowest speed, 800 rpm, won't cut it. (For perspective, I estimate that would provide 0.4 pool turnovers [I know the aforementioned post doesn't use a turnover rule of thumb, but this is just for some perspective].) If I run 1200 rpm for 8 hours in the middle of the day I get one full turnover, for $11/month total cost (based on weighted average TOU electricity prices). I have an alternate plan that varies between 800 and 1450 rpm for 14 hours and provides 2 turnovers for $18/month. I sweep and skim just about daily, and keep the pool covered 75% of the time.
Pump motor/seal life also is an issue, but my own general knowledge and what I've read here suggest that motor calendar life cannot be related in any simple way to hours run time per day.
Any comments appreciated.