Low
4 green flashes on Baxi 800

Your boiler is temporarily struggling to talk to its internal computer and should restart itself automatically without you needing to do anything.

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 complete its automatic self-resetIf the flashing continues, turn the power to the boiler off and back on at the fused spur switchEnsure any external room thermostats or smart controls have fresh batteries

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Related fault codes

E160View →5 green flashesView →

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