Over-temperature condition detected in wash or rinse circuit; E20 displayed and heating disabled.

Safety first: Turn off power immediately. Allow the machine to cool completely before servicing.

Steps to resolve:

• Check high-limit thermostat: Locate the Champion high-limit device on the tank or booster. Reset if it has a manual reset button. If it trips repeatedly, investigate cause.
• Inspect heater contactor: Ensure the heater contactor opens when there is no call for heat. If contacts are welded closed, replace the contactor.
• Verify temperature sensor: Test the associated temperature probe for correct readings. A failed sensor may cause the controller to overheat the water.
• Confirm control settings: Ensure temperature setpoints are within Champion specifications and have not been altered incorrectly.
• Test operation: After repairs, monitor a full cycle to confirm temperatures remain within safe limits.

When to call a technician: Overheating can damage tanks and seals; if the cause is not obvious, professional diagnosis is necessary.