Brand new underline RO install.

I installed a rainfresh undersink RO450 today all the lines are seated properly, plastic is off the filters and membrane. When I turn the water on at the supply it just runs contant water out the drain not filling the tank. I pulled the line on the membrane and there is water there, but if I pull the line that feeds the tank/finish after the ASO valve no water. I haven't checked the air gap yet, but baring that am I wrong in assuming its the ASO? I pulled the flow restriction in the Grey line and it seems fine.