Low
127 on Baxi 800

Your boiler has failed to heat the water to a high enough temperature to kill off any potentially harmful bacteria in the system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

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 heating and hot water timers allow enough time for the tank to reach full temperatureReset the boiler to see if the cycle completes successfully on the next attempt

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