Medium
127 on Baxi Suprima 30

Your boiler has failed to heat the water in your cylinder 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 set to at least 60°CEnsure your boiler control knob is not turned to the 'minimum' or 'off' positionCheck your programmer to ensure the hot water heating window is long enough (at least 1 hour) for the tank to reach full temperature

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