by just trial and error I suppose
That's how everybody has to do it. Every pool is unique (shape, size, weather patterns, geographical location, surrounding foliage, color, material, etc), and so every runtime scheme is unique.
The mention of "turn over" means whoever set up your pool is using "old school" methods which just don't apply. You can safely ignore what's been done before and experiment to find your own scheme.
If you're sanitizing with liquid chlorine, it takes very little runtime and RPM to get that chlorine distributed throughout your water body. So you don't really need to consider sanitation to determine runtime and RPM. So what do you consider?
There will be a "determining factor," or more than one, that governs runtime. The short list is:
- skimming
- filtering
- heating
- circulation
- cleaning
You take a best guess at runtime and RPM, and then try it out to see if all of your pool's needs are being met. If so, you can start to reduce the runtime, or the RPM, or both, until you determine the threshold where one or more of the needs is not being met. Then you goose the runtime/RPM back up a bit until they are. And you might have different settings throughout the year, or even throughout the day (I have both). So for examples:
If you have a salt water generator, it will require enough flow (RPM) and runtime to provide enough chlorine.
If you have a solar heater, that too will require enough flow (RPM) and runtime to provide enough heat. Same for a gas heater or heat pump.
In those two scenarios, everything else your pool will need will likely be covered within the runtime required for SWG and/or heating (that's how my pool works). I have to run eight hours in swim season for my solar heater to do its thing, and that eight hours covers what I need for my SWG. The pool stays clean, no leaves on the surface or bottom, so it is my heater that is the "governor." When I shut down the heater for the year, I only need four hours, and lower RPM, so it is the skimmer that becomes the governor in the off season.
If you have neither system, then you just watch the pool. If you reduce runtime/RPM and start to see more leaves floating around than you like, then you know you went too far. Same for clarity: if your pool water doesn't look crystal clear all the time, then you need more filtering. If you experience cooler/warmer patches of water, then you need more circulation. Or if you have more gunk on the bottom than you like, then you need more runtime on your cleaner.
And as I said, these requirements might change throughout the year, so you might have several settings. You might need more skimming or vacuuming in the fall. You might not use a heater in the winter. Etc.
So "trial and error" is the correct approach, and it's going to be a different scheme for every pool. Since a builder can't take the time to execute this process, they usually goose the pump and the runtime way higher than necessary, and that covers them. They don't get a call back that the pool is dirty, and so they're happy. But they don't pay the electric bill, do they, so the settings they leave you with are not usually in your best interest.
Jim's 1200 RPM works in his pool. I can't get away with less than 1500. My heater needs 2200, my vac needs 2300. Etc. So I even have different RPM requirements during a single day. Which is what pool automation computers were made for!
So there is no hours and RPM settings that work in every pool, you have to find your own.
