Technical description
Text display not yet defined
What causes this fault?
These codes appear when the boiler's internal computer is running through its initial boot-up sequence or performing a temporary software update. They are typically seen after the power has been switched off and back on, or following a brief interruption in the electrical supply. It is the system's way of checking all safety sensors and settings before it begins the ignition process.
This code may be seen more frequently during winter months if local power outages or grid fluctuations occur due to heavy storms.
DIY fix possible
Wait for 5-10 minutes for the sequence to completeObserve if the display changes to a temperature or status codeOnly contact an engineer if the code persists for more than 30 minutes