Low
4 green flashes on Baxi Suprima 100

Your boiler's internal computer parts are temporarily struggling to talk to each other, but the system should usually fix itself automatically.

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 up to 15 minutes for the boiler to self-resetPress the reset button briefly if the light continues to flashTurn the boiler power off and back on at the fused spur switch

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