Low Service
2 pulses No light on Worcester Bosch 28i Junior

Your boiler is currently in a manual testing mode used by engineers rather than broken, which is why it has stopped heating your home or water as usual.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

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 occurs when the service button has been pressed or held, accidentally putting the boiler into its manual 'Minimum' testing mode. It is not caused by a mechanical failure, but rather the internal software waiting for an engineer to finish checking the system. Because it is stuck at a low output, it might seem like the boiler is underperforming or ignoring your thermostat.

DIY fix possible

Locate the service button on the boiler control panel.Press the service button once to exit the current mode.Wait a few moments for the boiler to return to its standard operation status.

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