BoilerFaultCodesYour boiler is currently running at its maximum power for testing or maintenance purposes and is not indicating a fault.
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: Burner on with maximum CH power setting (Test Program)
What causes this fault?
This code appears when the boiler has been manually put into its 'high power' mode, usually by an engineer during a service or safety check. It occurs because the control buttons have been pressed in a specific sequence to lock the burner at its maximum output for testing. It is a status indicator rather than a component failure, so once the testing period ends, the boiler will return to normal operation.
DIY fix possible
Press the '+' and '-' buttons simultaneously to exit the test modeWait for the display to return to its normal temperature readingIf the 'h' persists, try a standard reset by pressing the 'reset' button
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