Built-in dishwasher with the door open and racks pulled out
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Measuring inlet water temperature at the appliance (dishwasher and washer cleaning complaints)

Dishwashers are designed for hot water at about 120°F at the unit, and DOE recommends about 120°F as the water heater setting for most homes. Long pipe runs deliver cold water first, which makes cycles longer and cleaning worse. A simple thermometer check separates a house problem from an appliance problem.

Cross-checked ~15 min easyBrands: All

Before you start

  • Hot water can scald: hold the cup by the base and keep hands out of the stream
  • Changing a gas water heater's setting is done only at its control knob per the heater label; any gas valve work is blocked and goes to a licensed technician

Diagnostic steps

Unlock all 6 steps with expected values

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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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Measuring inlet water temperature at the appliance (dishwasher and washer cleaning complaints) · OnCall Tech