Medium
127 on Baxi Suprima 100

Your boiler has failed to heat the water storage 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 set too low (it should be around 60°C).Ensure your hot water heating timings are long enough to allow the tank to reach full temperature.Reset the boiler by pressing the reset button to see if the cycle completes on the next attempt.

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