Low
4 green flashes on Baxi Profile

Your boiler is having a temporary moment of confusion between its internal brains, but it should fix itself automatically in a few minutes.

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 up to 10 minutes for the boiler to automatically reset the communication errorTurn the power switch to the boiler off and back on again onceEnsure there is no heavy electrical interference appearing near the boiler casing

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