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

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Legionella (cause of Legionnaires’ disease) protection temperature not reached

From this model's manual
Verified against the Baxi Suprima 30 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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