BoilerFaultCodesYour boiler has been left in its internal testing mode, which is usually only used by engineers during a service or setup.
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 max position.
What causes this fault?
This fault occurs when the 'Service' dial on the internal control board has been left in the maximum position after a visit from an engineer. It is a manual setting used to force the boiler to run at full power for testing purposes, rather than being an electronics failure. To clear it, the dial simply needs to be turned back to the normal 'off' or '0' position so the boiler can return to its regular operating mode.
This code is most common immediately after an annual service or a repair visit, regardless of the time of year.
DIY fix possible
Locate the horizontal dial on the front of the boiler control panel.Check if the dial is turned all the way to the right (maximum position).Turn the dial back to your desired temperature setting to exit service mode.
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A boiler cover plan would cover faults like 5 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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