BoilerFaultCodesTechnical description
Maintenance indicator – number of hours until the next maintenance
What causes this fault?
This code is triggered because your boiler has a built-in timer or run-hour counter that tracks how long it has been since its last professional inspection. It is not a mechanical failure but rather a proactive reminder set by an engineer to ensure the appliance remains safe and efficient. Once the pre-set time limit is reached, the system displays this notification to nudge you to book your annual maintenance.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register →