A little update.... The plumber has installed a second E.Vessel and an independent pressure gauge, which has revealed the boilers electronic pressure sensor is reading too high by half a bar. By going off the boilers digital readout I've been over filling. If I try and balance the pressure reading by filling for a low pressure then the boiler won't start as it thinks it's under pressure....( If that makes sense)...So a replacement sensor tomorrow.
The damage... £229 for all the parts and repairs, but hopefully a happy boiler.
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