Low
4 green flashes on Baxi Suprima 50

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

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 a few minutes for the boiler to automatically reset itself.If the flashing continues, turn the control knob to 'Reset' for 5 seconds and then back to your desired setting.Check that any external thermostats or timers are calling for heat.

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