I have th exact same problem as the originator.
Split off of this topic. JasonLion
Skimmer draws water in very well. Floor drain - nothing. I can put leaves right on the opening for the floor drain and nothing happens.
This is my pool:
7 years old
11,000 gallon salt water pool
4 cartridge filters
Auto cleaning with pop-ups
Single motor/pump for cleaning
Separate single motor/pump for water feature
Whisper Flo pumps with filter basket
Century Centurion motors
Two pipes under the skimmer basket & the one away from the pool accepts the vacuum hose
I have the water regulator below the skimmer basket that is pictured above about 1/3 open.
So far I have:
Cleaned the cartridge filters
Cleaned both the skimmer and pump baskets
Turned the black valve in all directions**
**NOTE: As a sidebar I do not know what turning this valve does or what it should be set at. Opposite the handle side on the valve is labeled "OFF"
The vacuum has normal suction, its just that the flow is not drawing in any water, leaves, etc. from the dual floor drains.
Any help would be greatly appreciated.