Low
4 green flashes on Baxi 400 Combi (range)

Your boiler is temporarily struggling to talk to its internal computer and should automatically fix itself and restart shortly.

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 10 minutes for the boiler to self-resetIf the error persists, turn the selector switch to the reset position for 5 secondsCheck that any external room thermostats have fresh batteries

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Related fault codes

E168View →E133View →

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