Whenever my D/W drains, the airgap overflows. I couldnt remove the hose btwn the disposal and airgap and am not sure of problem. Could it be clogged? What means is there to test this? Next steps to resolve the matter?
It could be clogging or the piece on the disposer that it is connected to could have corroded to the point the opening has closed up. If that is the case, when you remove the hose, you will need a new disposer.
The most common problems are either a clogged drain that allows water to back up, or a kink in the hose that allows the water to back up into the air gap.
Run your disposer (with running water) for a few seconds before running the DW. When the DW is running, check the hoses for kinks, even minor ones. Some hoses will collapse when heated by the hot water from the DW, but not so apparent when they’re cold. Any constriction at all will cause water to back up through the air gap.
If a hose is the problem, replace it with a thicker hose that won’t kink when heated.