BoilerFaultCodesYour boiler is not in a fault state; it is simply indicating that it is running at its maximum power level, usually during a service check or a high demand for heat.
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: Display change from ‘0’ to ‘00’ indicating maximum rate
What causes this fault?
This code appears when the boiler has been manually set to its highest output level, often during a safety check or efficiency test performed by an engineer. It indicates that the burner is firing at full capacity to meet an intense demand for heat or to allow for accurate gas pressure measurements. It is a status indicator rather than a mechanical failure, showing that the system is operating at its limit by design.
DIY fix possible
Wait for the boiler to complete its current heating cycle.Ensure that the selector switch has not been left in the 'test' or 'max' position.If the display stays on '00' indefinitely, try resetting the boiler using the main control knob.
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