Blocking fault 1/y/ (3/1/8) - Flue gas sensor contacts open

What does 1/y/ mean?

The contacts for the flue gas sensor are open, indicating a broken connection. This is a blocking fault, stopping heating and domestic hot water. A manual reset is needed once the connection is restored.

• Open circuit in flue gas sensor wiring
• Loose connection
• Defective flue gas sensor

Click steps to track your progress.

1. 1

   Press the 'Reset' button on the BC10 basic controller.

2. 2

   Check any accessible connections to the flue gas sensor for looseness.

3. 3

   If the fault reoccurs, contact a qualified service technician to inspect the sensor and its wiring.