BoilerFaultCodesYour boiler is reminding you that its scheduled annual service is now due, but it should continue to provide heating and hot water as normal.
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: Control mode - Maintenance
What causes this fault?
This code is triggered by an internal countdown timer within the boiler's control unit, which tracks operating hours or calendar months since the last professional visit. It is not caused by a mechanical failure or a broken part, but rather a pre-set reminder to ensure the appliance remains efficient and safe. Once your Gas Safe engineer completes the maintenance work, they will reset this timer to clear the notification.
This code often appears in autumn as homeowners turn their heating back on, revealing that the twelve-month service interval has passed during the summer months.
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 for a qualified engineer in your area.
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A boiler cover plan would cover faults like 0F — no call-out fees, no surprises.
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