Medium
127 on Baxi Assure

Your boiler has failed to heat the hot water tank to a high enough temperature to kill off bacteria, which is a standard safety routine.

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 not set too lowEnsure your hot water timer is set to allow the water to heat up fully for at least an hourReset the boiler to see if the cycle completes successfully on the next attempt

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