Built-in dishwasher with the door open and racks pulled out

Generic photo: Castorly Stock · Pexels License

Dishwasher water backs up into the sink or out of the air gap

When dishwasher water reaches the sink, the dishwasher pump is working and the restriction is downstream: a clogged sink drain or disposer outlet, a blocked air gap or a kinked hose. Sink water entering the dishwasher points to a missing air gap or high loop, or a failed check valve.

Cross-checked ~40 min easyBrands: All

Before you start

Power off the disposer and dishwasher before reaching into either
Never put a hand in a disposer; use tongs

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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