water will shoot out from the airgap whenever I start the dishwasher. I checked the air gap and pipe and found somewhere from the airgap to the disposer is clugged. Anyways I want to know if the drain pipe should be straight to the disposer or a "u-shape" trap should be used...the one in my house now is a "u-shape" because the pipe is kind of long. thank you for your help if possible. I just bought his condo and I really want things to work. thank you again.