We have a plaster pool with a floor drain (old style cover) in the deep end, a skimmer in the shallow and a port to attach the floor vac in the side/center. There are 2 return pipes that lead to a jandy valve which leads to the strainer/pump. At the 12 o'clock position the skimmer works, at 6 o'clock the vacuum and at 9 o'clock (give or take) a combo of the two. I have assumed that the floor drain and skimmer share the same return line.
I cannot figure out how to adjust the floor drain to get better suction from that drain. The only other visible valves are on the return side. One is the slide valve for backwashing. One leads to a small pipe which feeds the side spray which cools the water. The other is an orange valve on the main return (I am not sure what that is for so any insight is appreciated).
When I use the brush to slowly sweep debris over the floor drain, it doesn't suck down into the drain as I would expect. Even when I go super slowly and stop short of the drain to allow the momentum of the debris and the suction power of the drain to work, it still seems that the dirt just kicks up and resettles anywhere but into the drain. We do not have one of those safety covers on that drain so I would expect it to be pretty powerful. Any thoughts on what could be happening?