BoilerFaultCodesYour boiler is currently running a self-test at its highest power level and this code is an information message rather than a breakdown.
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: Indicating maximum rate (during calibration)
What causes this fault?
This code appears when the boiler is performing a self-diagnostic test to ensure it is operating safely at its highest output. It is triggered during a manual calibration check by an engineer or during a high-demand period where the system is testing its combustion limits. It does not indicate a breakdown and simply means the boiler is working at full capacity to monitor its own performance.
DIY fix possible
Wait for the boiler to finish its calibration cycleEnsure hot water taps are closedIf the code persists for more than 30 minutes, try resetting the boiler once
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A boiler cover plan would cover faults like 00 — no call-out fees, no surprises.
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