The results are in the picture.
Both skimmers stopped working and the spa started draining.
The only time I saw a definite improvement in skimmer action was by rotating "B" but the lower (shallow end) skimmer stopped working. Nothing stopped just the upper (deep end) skimmer from working. As previously stated, there were no labels when the plumber arrived and none when he left. I will try to go through some old photos and see if I can tell how the pipes were connected underground. But I think it may not show enough for what I need.
The builder spec was for a 1.85hp pump which I upgraded to a 2.7 vsp. So on high, I can more action from the skimmers but I think there must be too much water coming in from the bottom drains. If the skimmers and drains are tied together in the ground, the only way I can see in solving this issue would be to install some sort of restriction in the drain itself. If they are tied together, the pressure of the water on the bottom drains would likely make it much easier for water to flow from there than from the skimmers. I hope that this is not the case and there is something that is just not plumbed correctly at the pad.
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