Low
4 green flashes on Baxi Suprima 30

Your boiler is experiencing a brief communication hiccup between its internal electronic parts and should correct 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.

What the manual says

Manufacturer manual

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

From this model's manual
This code was read directly from the manufacturer service manual for this model.
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

Monitor the boiler for a few minutes as it should self-resetIf the error persists, turn the control knob to the 'Reset' position for 5 secondsEnsure any external controls or thermostats are calling for heat

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