Medium
127 on Baxi Suprima 50

Your boiler hasn't been able to heat the water hot enough to kill off harmful bacteria in the system, which is a safety setting meant to keep your water clean.

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 turned up to at least 60°C.Ensure your heating and hot water controls are set to run for long enough to reach full temperature.Press the reset button on the front of the boiler to clear the temporary warning.

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