Blocking fault 4/p/ (2/2/1) - Safety temp sensor contacts interrupted

What does 4/p/ mean?

The contacts for the safety temperature sensor have been interrupted, indicating an open circuit or loose connection. This safety fault stops heating and domestic hot water. This is a blocking fault, requiring a manual reset.

• Open circuit in sensor wiring
• Loose connection
• Faulty safety temperature 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 safety temperature sensor for looseness.

3. 3

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