BoilerFaultCodesYour boiler is currently stuck in a manual testing mode used by engineers 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: Not a fault code: Service mode selected to max, press service button to return to normal.
What causes this fault?
This issue occurs when the service button has been manually pressed, putting the boiler into a high-power test mode often used for internal checks. It is not an internal component failure, but rather a specific settings mode that prevents the boiler from responding to your normal heating controls. To fix it, the service button simply needs to be pressed again to deactivate the override and return to everyday use.
DIY fix possible
Locate the button with a 'spanner' or 'service' icon on the control panel.Press and hold the service button briefly until the lights stop pulsing.The boiler should return to its normal standby or running mode.
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A boiler cover plan would cover faults like 5 pulses, Lockout reset: No light — no call-out fees, no surprises.
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Worcester Bosch Greenstar 25Si 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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