Quick answer
Check the heating element for damage, ensure the water supply is hot, and test the thermostat. Replace faulty parts if needed.
Confirm the symptom
- Dishes remain wet after a full cycle
- No visible steam during operation
- Water entering the dishwasher is cold
- Dishwasher runs but dishes aren't sanitized
- Heating element appears cracked or burned
Tools and prep
- Screwdrivers (flathead and Phillips)
- Multimeter for testing electrical components
- Rubber gloves and safety goggles
- Flashlight for inspecting interior
- Owner's manual for model-specific guidance
- Turn off power at circuit breaker before starting
Step-by-step troubleshooting
- Check Water TemperatureDo: Verify the home's water heater is set to at least 120°F and the hot water line is connected to the dishwasher.Observe: Water entering the dishwasher is hot.Means: Cold water supply prevents proper heating and drying.Next: If water is cold, adjust the water heater or check connections.
- Inspect Heating ElementDo: Visually check the heating element at the bottom of the dishwasher for cracks or discoloration. Use a multimeter to test for continuity.Observe: Heating element shows visible damage or no continuity.Means: A faulty heating element cannot generate heat.Next: Replace the heating element if damaged or non-functional.
- Test ThermostatDo: Locate the thermostat (usually near the heating element) and test it with a multimeter for continuity.Observe: Thermostat fails continuity test or shows irregular readings.Means: A faulty thermostat prevents the heating element from activating.Next: Replace the thermostat if it's not working.
- Check Hi-Limit ThermostatDo: Test the hi-limit thermostat (safety device) with a multimeter to ensure it's not tripped or damaged.Observe: Hi-limit thermostat shows no continuity or is physically damaged.Means: A tripped hi-limit thermostat cuts power to the heating element.Next: Replace the hi-limit thermostat if faulty.
- Inspect Water Inlet ValveDo: Check the water inlet valve for clogs or damage that might restrict hot water flow.Observe: Valve is clogged or not opening fully.Means: A faulty valve can prevent hot water from entering the dishwasher.Next: Clean or replace the water inlet valve as needed.
- Test Control BoardDo: Use a multimeter to test the control board for proper voltage output to the heating element and thermostat.Observe: Control board shows no voltage or erratic readings.Means: A malfunctioning control board may not send power to heating components.Next: Replace the control board if it's not functioning correctly.
- Check Drain HoseDo: Ensure the drain hose is not kinked or clogged and is properly positioned above the sink drain.Observe: Drain hose is blocked or improperly installed.Means: Poor drainage can affect the dishwasher's ability to dry effectively.Next: Unclog or reposition the drain hose.
- Verify Vent SystemDo: Inspect the vent system (if applicable) for blockages or damage that might hinder airflow during the drying cycle.Observe: Vent is clogged or damaged.Means: A blocked vent can prevent proper air circulation for drying.Next: Clean or repair the vent system.
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Faulty Heating Element The heating element generates heat for drying. If damaged, it can't produce sufficient heat. | Common | Medium | Heating element |
| Malfunctioning Thermostat The thermostat controls when the heating element turns on. A faulty one can prevent heating. | Common | Medium | Thermostat |
| Tripped Hi-Limit Thermostat This safety device cuts power if the dishwasher overheats. It may remain tripped after a malfunction. | Sometimes | Medium | Hi-limit thermostat |
| Cold Water Supply If the dishwasher is receiving cold water instead of hot, it can't heat properly. | Sometimes | Easy | Water supply line |
| Clogged Water Inlet Valve A clogged valve restricts hot water flow into the dishwasher. | Sometimes | Easy–Medium | Water inlet valve |
| Faulty Control Board The control board sends power to the heating components. A malfunction can prevent heating. | Rare | Hard | Control board |
| Blocked Drain or Vent Poor drainage or airflow can hinder the drying process. | Sometimes | Easy–Medium | Drain hose or vent system |
Parts matching
Common parts needed for a dishwasher not heating or drying include:
- Heating element (most common replacement)
- Thermostat and hi-limit thermostat
- Water inlet valve
- Control board (less common)
- Drain hose or vent system components
Always match parts to your dishwasher model using the owner's manual or model number for compatibility.
When to call a professional
- If you're uncomfortable working with electrical components
- If the dishwasher is under warranty and DIY repairs may void it
- If you've replaced all accessible parts without resolving the issue
- If the control board needs replacement (requires advanced skills)
- If water leaks or electrical shorts are present during inspection
FAQ
Why is my dishwasher not drying even though the heating element looks fine?
The thermostat or hi-limit thermostat may be faulty, preventing the heating element from activating. Test both components with a multimeter.
Can cold water cause a dishwasher to not dry properly?
Yes. If the dishwasher is receiving cold water instead of hot, it can't generate enough heat for effective drying. Check the water supply connections.
How do I know if the thermostat is the problem?
Test the thermostat with a multimeter for continuity. If it shows no continuity or erratic readings, it likely needs replacement.
Is it worth repairing an old dishwasher that won't heat?
Consider the age and cost of parts. For dishwashers over 8–10 years old, replacement may be more cost-effective than repair.
Can I test the heating element myself?
Yes. Turn off the power, remove the lower panel, and use a multimeter to check for continuity. No continuity means the element is faulty.