Symptoms
- Dishes come out only partially clean with greasy residue
- Tub feels only warm, not hot, right after a cycle
- Detergent doesn't fully dissolve
- Poor drying performance alongside poor cleaning
Likely causes
- CommonHome water heater set too lowIf the water heater is below about 120°F, the dishwasher starts with water that's too cool.
- CommonLong cold water run before it reaches the dishwasherIf the dishwasher is far from the water heater, the first fill can be mostly cold water.
- PossibleFailed heating elementThe internal element that boosts water temperature during the wash can burn out.
- PossibleFaulty thermostat or thermistorA sensor failure can cause the unit to under-heat even with a working element.
What to do
- Check your water heater's thermostat setting and raise it to around 120°F if it's lower.
- Run the kitchen faucet nearest the dishwasher on hot until steaming before starting a cycle.
- Use a cooking thermometer to check the water temperature at the tap closest to the dishwasher as a baseline.
- Select a heated or sanitize cycle option if your model has one, which forces extra internal heating.
- If water is properly hot at the tap but dishes and the tub still feel lukewarm after a cycle, the internal heating element may have failed.
- Have a technician test the heating element and thermistor if pre-heating the water doesn't solve the problem.
Tools and parts
- Cooking thermometer
Dishwasher heating elementSearch: “dishwasher heating element replacement”
When to call a pro
If hot water is confirmed reaching the dishwasher but the tub still runs cool, have a technician test and replace the heating element.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.