Medium
127 on Baxi Suprima 70

Your boiler has failed to heat your hot water tank to a high enough temperature to kill off potentially harmful bacteria.

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 turned down too low.Ensure your hot water 'on' times are long enough for the tank to reach full temperature.Press the reset button on the boiler faceplate.

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