BoilerFaultCodesYour boiler has been left in a manual testing mode after a service or inspection and needs to be switched back to its normal operating setting.
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: Service mode switch in min position.
What causes this fault?
This issue occurs when a technician accidentally leaves a physical switch on the internal control board set to 'minimum' after performing a service or safety check. Because the boiler is being told to stay at its lowest power setting for testing purposes, it cannot respond to your thermostat's request for full heat. It is a simple human error where a manual override was not deactivated before the boiler casing was put back on.
DIY fix possible
Locate the service mode switch (or dial) on the boiler control panel.Ensure the switch is moved from the 'Min' or 'Service' position back to the 'Normal' or 'Off' position.Perform a simple reset by pressing the reset button to clear the flashing light.
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A boiler cover plan would cover faults like 2 pulses — no call-out fees, no surprises.
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Worcester Bosch Greenstar 12Ri is discontinued — time for a new one?
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