Heater shows E06 and stops operation; may start then quickly shut down

Safety first: Turn off power at the breaker before opening the electrical compartment.

• Locate outlet sensor: Identify the outlet temperature sensor (NTC2) on the heater’s water outlet manifold or pipe.
• Inspect cable and connector: Check for physical damage along the cable. Unplug the connector at the sensor and at the control board, inspect for corrosion, clean if necessary, and reconnect securely.
• Verify sensor seating: Ensure the sensor is properly inserted into its pocket or firmly attached to the outlet pipe.
• Compare temperatures: If you have a multimeter and NTC resistance chart from BWT, measure sensor resistance at known water temperature to verify it is within specification.
• Power cycle: Restore power and test the heater. Observe if E06 reappears.

Persistent E06 after wiring checks usually indicates a failed outlet NTC sensor. Replace the sensor. If the new sensor does not resolve the fault, the control board may need replacement by a professional.