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4 green flashes on Baxi 100/2 HE Plus

Your boiler's internal computer parts are temporarily struggling to talk to each other, but the system should usually fix 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

Wait up to 15 minutes for the boiler to self-resetPress the reset button briefly if the light continues to flashTurn the boiler power off and back on at the fused spur switch

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