Need help with tricky installation of ball valves

[riny]

@Dirk I just want you to know that you've convinced me to add a FlowVis this spring when I put in a VSP. For my size pool, 15 gpm will turn the water over 2x per day, but I had no idea what speed to use on the VSP to get that flow rate, nor how to optimize when using the heat pump. The side-mount (saddle-style) flow meters just look so cheap and unreliable. This looks like a much better option, and if I put it between the heat pump bypass and the SWG then it can double as the check valve. Good stuff!

 

[Dirk]

Just want to caution you to eliminate the turnover rate as a reason to install a vis. Turnover is a myth, and that practice is not condoned here.

The amount of runtime for a pump are determined by several factors, none of them are turnover:

- How long you need to pump to heat the pool.

- How long you need to pump to produce chlorine from an SWG.

- How long to circulate the pool to remove leaves through the skimmer.

- How long to filter to achieve the water clarity you desire.

- How long to circulate to distrubute chemicals.

- There may be others depending on your setup (water falls, spas, vacuuming, etc).

Generally, the one of those that requires the most runtime establishes the runtime. The other tasks will be accomplished during that same run. So when you need to heat, your runtime might be 12 hours. Everything else will get done during that 12 hours. If you're not heating, maybe it's the SWG that has to run for 10 hours. Circulation to achieve a clean surface and clear water is subjective, and dependent on how dirty your pool gets. Maybe that can get it done in 8 hours, or as little as 4 hours, or more, or less, that's up to you. And circulating chlorine doesn't take long at all, so in mid-winter, when you don't need to run the pump for anything else, your runtime might only be an hour or two.

My runtime varies by season, anywhere from 3 hours up to 14.

You set the runtime based on the needs of you and your pool, not some arbitrary turnover number that has nothing to do with what actually needs to get done.

The other reasons for a Vis our sound.

 

[riny]

Good to know, thanks. I'm still very new at this obviously. Looking at it from a pure cost perspective, 1/2 the pump speed uses about 1/4 of the electricity, so "my cousin who's had a pool for a long time" (yeah we all have one of those) told me with the VSP to run it 24h/day on the lowest possible speed that gives enough total circulation. Obviously the heater needs a specific flow rate when it's in use; I didn't realize the SWG does too, but it makes sense. And I suppose if there's technically enough turnover but really not enough velocity to pull the leaves into the skimmer, then that's a problem. I guess this means it will be more trial-and-error next year than just setting it for a specific gpm and letting it run!

 

[Dirk]

You vary both runtime and speed to achieve the desired results. One of our experts runs 24 hours at 1200 RPM. Works for his pool. Others run many hours a day at higher RPMs because their skimmers need the extra whirlpool effect. For me, it's about satisfying my rooftop solar heater. And yes, it's all trial and error. That's why TFP doesn't suggest turnover, because every pool is different: shape, size, wind conditions, amount of dirt that gets into the pool, swimmer load, etc. It has to be case by case.