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4 green flashes on Baxi Profile Prima

Your boiler has temporarily lost communication between its internal electronic parts but should automatically try to restart itself 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.

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 itselfTurn the main power switch to the boiler off and back on againEnsure any external room thermostats or timers are set correctly

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3 green flashesView →5 green flashesView →

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