Heater shows F07 and shuts down; may occur during operation as water warms.

Safety first: Disconnect power before opening the control panel or touching sensors.

• Locate inlet sensor: The inlet sensor is usually mounted on or near the heater’s inlet header. Refer to the Thermeau wiring diagram for identification.
• Inspect sensor and harness: Check for physical damage to the sensor body or cable. Ensure the harness is not pinched by panels or rubbing against sharp edges.
• Verify connection at board: Remove and reinsert the sensor connector on the control board to ensure a solid electrical connection.
• Check sensor seating: If the sensor sits in a thermowell, confirm it is fully inserted and making good thermal contact.
• Replace if necessary: If F07 persists and the displayed inlet temperature is erratic or unrealistic, replace the inlet thermistor with the correct Thermeau part.