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

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 70 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 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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