Medium
127 on Baxi Titanium

Your boiler has failed to heat the water to a high enough temperature to kill off bacteria, usually because the hot water hasn't been used or heated fully for a while.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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

Legionella (cause of Legionnaires’ disease) protection temperature not reached

DIY fix possible

Check that your hot water cylinder thermostat is set to at least 60°C.Ensure your hot water heating times are set long enough for the tank to reach full temperature.Restart the boiler and allow it to run a full hot water heating cycle.

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