Low
127 on Main Eco Elite

Your boiler has failed to heat the water to a high enough temperature to complete its automatic routine cleaning cycle that prevents bacteria growth.

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.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Main Eco Elite 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 temperature dial is set to its normal operating position, not at its lowest.Ensure the boiler has been left switched on consistently so it can complete its timed weekly heat cycle.Restart the boiler using the reset button to see if the cycle completes successfully on the next attempt.

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