BoilerFaultCodesYour boiler is not broken; it has simply been put into a temporary testing mode used by engineers.
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: Not a fault code. Service mode selected to max, press service button to return to normal.
What causes this fault?
This occurs because the 'Service' button on the control panel has been pressed, manually placing the boiler into a high-fire testing mode. It is not an internal component failure, but rather a specific setting usually used by engineers to check gas pressures or emissions. Your boiler is simply following a command to run at maximum output for maintenance purposes.
DIY fix possible
Locate the button with the 'spanner' or 'service' icon on the control panel.Press and hold the button for a few seconds until the flashing blue light stops.The boiler should return to its normal standby or operation light.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Blue light: 5 pulses, Lockout reset button: No light — no call-out fees, no surprises.
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Worcester Bosch Greenstar 12i System is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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