My dishwasher airgap overflows large amounts of water when I run a load, so much that it spills all over the counter as well as the sink. I think that a line needs to be cleaned out but I don’t know which line and where it would be under sink. I also have a garbage disposal. And if a line does need to be cleaned out, what is the best way to do it?
The air gap on your sink most likely has a piece of food in it. Does the garbage disposer drain ok? If so take apart and clean air gap or replace with new. Good Luck, Bill The Local Plumber Tustin, California http://www.TheLocalPlumber.com