Built-in dishwasher with the door open and racks pulled out
Generic photo: Castorly Stock · Pexels License

Loud bang or knock in the pipes when the dishwasher fills or stops filling

The dishwasher's solenoid inlet valve closes fast, and in a high-pressure or loosely strapped line the water slams to a stop (water hammer). The fix is usually on the plumbing side: lower the pressure, add an arrester on the supply side of the valve, and secure the pipes. A valve that chatters can also be at fault.

Single source ~45 min moderateBrands: All

Before you start

  • Close the supply valve and turn off the breaker before working on the inlet valve or supply line

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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Loud bang or knock in the pipes when the dishwasher fills or stops filling · OnCall Tech