Waiting for the pool builder to install some check valves but after some more reading on the topic, I'm starting to get a bit concerned.
My pump is about a 40-50ft run and 10ft higher than the pool. When it's running the basket looks mostly empty to me - maybe half full at best? (is this normal??)
But as soon as I turn it off, it will drop lose prime with a few minutes. I've had to set the speed on my intelliflo vs to around 3400 for 5 minutes for priming. When it comes on after sitting overnight, I get these big air bubble explosions as the returns pump out all the air.
Beyond my thinking that those air "bombs" are not a good idea for the system, I also started thinking that doesn't seem like something that should be happening anyway, even in this system. In my mind, this *should* be a closed system (or at least mostly so). It would seem to me that, even though the water lines are above the pool, the "act" of them running back into the pool should create some sort of vacuum unless there's a lot of air leak somewhere - kind of like putting my thumb over the straw when it's full of coke. The straw stays full until I let take my thumb off and let the air "in" the system.
The other problem is that one morning, I heard the VS running dry (and loudly!) after a half an hour. I thought these things had a priming alarm on them?? That was actually when I cranked up the priming speed set on it. But this worries me too because it runs "dry" a lot because of this - as much as 3-4 minutes, depending on how long the systems's been off.
So...all that having been said...am I way off base? Or does any of that make sense? And do I have a lot to worry about?