Pump sucking air when using vacuum

[robt113]

I'm having the same exact problem with my 20x40 in-ground with 2 skimmer intakes. Pool works perfect when under normal operation, pump basket is always solid water. Only have problem when vacuuming. Put the vac hose (full of water) with the skimmer plate over the skimmer basket, and I still have a pump basket full of solid water, but try to close down the other skimmer port to give the vac some good suction and the pump basket fills with air and loses prime. (New hose, new skimmer plate,pretty new pump, new filter, Pressurized line from pump to skimmers with 30 lbs. of air, held for 15 mins. (no pressure lost) and new pump lid square rubber gasket. Now I take the hose and put it in the skimmer port (Minus the skimmer plate and of course without the basket, using only the pump b
asket to catch debris) and you can vacuum with the other skimmer port closed ,with only a large bubble of air in the pump basket. This is what I've been doing to vacuum. Anybody have any idea what the problem is? This system used to work perfect at one time, seems to be getting worse every year. Try either skimmer and it's the same exact problem

 

[J20832]

Yes, you are increasing the suction on your vacuum hose when you close the other skimmer port. The vac hose, under such pressure, probably leaks some air at the collar (at least mine do). When you put the hose in without the skimmer plate, you are probably submerging the collar of the vac hose and so there is no air being sucked in, just water from your skimmer. The large air bubble is probably just from air in the line that is making its way to the pump basket.

One workaround that has been successful for me is duct tape. Tape around where the vac line collar meets the hose and you should be getting little or no air sucked in.

 

[harleysilo]

My hose has one end that doesn't swivel, and one end that does. If you put the swivel end in skimmer it will suck air from the swivel connection.....swivel end goes on vac head....