The red fault light comes on when we are running hot water or the heating is on, we reset the unit with the switch on the front, turn it anticlockwise, and it works for quite a while then does it again, so we reset it again, its been doing this for weeks now. I have changed the circuit board with no success.
How long has your boiler been doing this, need to get a Gas Safe guy to come in and do a few checks may have something to do with the flame sensing electrode.
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