Your boiler is having a temporary 'handshake' issue between its internal electronic brains, but it should fix itself automatically.
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.
Technical description: Communication error between printed circuit board (PCB) and control. Temporary error, will self reset.
What causes this fault?
This fault occurs when the internal control panel and the main electronic circuit board momentarily lose their connection with each other. It is often caused by a minor electrical glitch or a brief delay in data being sent between these two components. In most cases, it is a temporary hiccup in the boiler's internal computer system rather than a mechanical failure.
DIY fix possible
Wait for the boiler to self-reset as this is often a temporary glitchIf the flashing continues, turn the selector switch to 'Reset' for five secondsMonitor the boiler to see if the green flashes return
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