BoilerFaultCodesThis is an advisory message showing you how many hours your boiler has spent heating your hot water cylinder.
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: Operating hours hot water generation
What causes this fault?
This is not a fault, but rather a digital log of how hard your boiler has worked to provide hot water. It records the total number of hours the burner has been active specifically for heating your cylinder since the boiler was first installed. This data helps engineers understand your usage patterns and the overall health of the system's heating components.
DIY fix possible
Press the 'Back' or 'Menu' button to return to the main displayNo action is required as this is a status information code, not a fault
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A boiler cover plan would cover faults like D.81 — no call-out fees, no surprises.
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