Low
4 green flashes on Baxi Suprima 70

Your boiler is having a temporary 'conversation' issue between its internal parts and should fix itself momentarily 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.

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

Wait for the boiler to automatically reset itselfIf the flashing continues for more than 10 minutes, turn the control knob to reset and back to the desired temperatureEnsure the power supply to the boiler is stable and not being interrupted

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