Low
4 green flashes on Baxi Suprima 115

Your boiler is having a temporary glitch in its internal electronic communication and is attempting to fix itself.

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

Communication error between printed circuit board (PCB) and control. Temporary error, will self reset.

DIY fix possible

Wait for the boiler to automatically reset itselfTurn the power to the boiler off and back on again at the fused spurIf the lights continue to flash, press the 'Reset' button

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