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/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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Related fault codes

110View →125View →

All 37 fault codes on the Eco Elite

Seeing a different code? Every code this model can display, in one place.

1 green flash1 red flash2 red flashes3 green flashes3 red flashes4 green flashes4 red flashes5 green flashes5 red flashes6 green flashes6 red flashes110119125133160E1E2E3E20E28E50E110E119E125E133E160FLASH FLASH ONFLASH OFF FLASHFLASH OFF ONFLASH ON FLASHFLASH ON ONON FLASH FLASHON FLASH ONON OFF FLASHON ON FLASH

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