BoilerFaultCodesYour boiler has accidentally been set to a manual service mode and simply 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 min, press service button to return to normal.
What causes this fault?
This issue occurs when the service button has been accidentally pressed or held down, which triggers a manual override intended for maintenance testing. Instead of a malfunction, the boiler is simply stuck in a low-power setting used by engineers to check emissions. It stops responding to your thermostat because it is waiting for a command to exit this specific tuning mode.
DIY fix possible
Locate the 'Service' button on the boiler control panel.Press and hold the 'Service' button for a few seconds until the light stops pulsing.The light should return to a steady state or turn off, indicating the boiler is back in normal mode.
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A boiler cover plan would cover faults like 2 pulses (No light) — no call-out fees, no surprises.
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Worcester Bosch Greenstar 24i Junior 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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