Medium
2 pulses on Worcester Bosch Heatslave

Your boiler has been left in a maintenance setting intended only for testing, which prevents it from operating normally.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Check service mode switch is in minimum position

DIY fix possible

Locate the control panel on the front of the boiler.Find the small 'Service' or 'Mode' switch behind the pull-down cover.Ensure the switch is moved back to the 'Normal' or 'Minimum' position rather than 'Max'.

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