BoilerFaultCodesYour boiler is currently running a manual test mode at its highest power setting and is not experiencing a mechanical failure.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Test program: Burner on with maximum CH power setting.
What causes this fault?
This code appears when the boiler has been manually placed into a high-fire testing mode, usually by an engineer during a service or installation. It is not a breakdown, but rather a status indicator showing the burner is forced to run at its maximum output for performance checks. If you see this and haven't touched the controls, it is likely that the testing buttons were pressed accidentally.
This code is most common in summer or autumn when annual service visits are typically scheduled.
DIY fix possible
Press the '-' button once to exit the test modeAlternatively, wait for the test cycle to finish automatically after a few minutesThe display should return to showing the system pressure or temperature if successful
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