If you want to have a good laugh, read on.
After reading Hydarulic 101, I set to reduce my suction head loss. This happened quite a while ago while I was hot at it.
I did all these is because I was ****** that my PB used 1.5" all around. I found that out from the flowmeter. I am paying for resistance at the 50GPM flow ( best flow I can ever get ) I am having, in other words I should have more flow if 2" pipes are used all around. That's what the pipe calculator showed me.
Due to the nature of the concrete pool, there is no way I can do anything to change the plumbing that is already set in concrete. So my only other method is to modify whatever pipes that are not embedded in concrete and somehow improve it. So I thought...
I don't have any hydraulics background, so the fun is learning by doing....
This is the original set up that came when pool was built.
During normal operation, the TANK valve and the DRAIN valve will always be opened.
There are two spring operated check valves on the suction circuit. One is right before the pump and the other is at the balancing tank suction pipe, at the very end of the pipe.
My test number for the suction is 11.5hg with check valves installed, TANK & DRAIN valves opened.
Without check valves ( i remove the internal parts ) the number is 8hg, TANK & DRAIN valved opened.
So the 2 check valves caused 3.5hg increase, which is equals to 3.9 feet loss of head according to the formula.