01It started after a new disposal or dishwasher installation
Whirlpool’s new-installation drainage guidance identifies the disposal inlet knockout, disposal obstruction and drain-hose routing as possible items in an installation assessment. Ask the installer to check the completed connection using the actual model instructions. These are questions for that review, not instructions to remove a plug or rearrange a hose yourself.
Notice next: Record which appliance was replaced, who connected it and whether this was the first use after the work.
02The same setup previously worked without countertop discharge
GE discusses material accumulated in the air gap and recommends a plumber when the leakage concern persists. Report the change from normal operation and request an air-gap and drain-connection assessment. This does not establish where a restriction is or whether any particular part needs replacing.
Notice next: When did it first happen, and had the sink or dishwasher behaved differently beforehand? Use what you already noticed.
03The air gap or drain arrangement changed during remodeling
Ask the contractor to identify what was changed and provide the installation record. Have the installer or plumber compare the completed arrangement with the dishwasher instructions and applicable local requirements. A recent remodel does not by itself prove incorrect work.
Notice next: Was the air gap, sink, disposal or drain connection moved or replaced? Save the work description and any existing before-and-after photos.
04The water may be coming from somewhere else
Distinguish water leaving the air gap from water rising in the sink, appearing inside the cabinet or remaining in the dishwasher tub. Describe each observed location separately. A sink that seemed to drain normally does not identify the cause of the air-gap discharge.
Notice next: Where did water first appear? If you did not see the starting point, say that it is unknown rather than recreating the spill.