Locking fault 2/p/ (2/1/2) - Heating water temperature increased too rapidly (over 40°F/s)

What does 2/p/ mean?

The flow temperature sensor has detected an excessively rapid increase in heating water temperature (over 40°F/s or 5°C/s). This is a safety lockout, often indicating insufficient water flow or an overheating condition. This is a locking fault.

• Low water flow
• Circulation pump failure
• Air in the system
• sensor malfunction

Click steps to track your progress.

1. 1

   Check the system pressure and top up if necessary according to the manual.

2. 2

   Allow the boiler to attempt an automatic reset.

3. 3

   If the fault persists, contact a qualified service technician to inspect the circulation pump and sensors.