Glow worm 30 cxi fan pulsing



I have a 30 cxi about 7 years old, no real issue with other than recently I changed the diverter valve components.
Any way I arrived home today and noticed the boiler fan pulsing and running permanently no demand for heating or hot water.
I switched it all off and tried again a few minutes later but the same again digital gauge began racing up and down between 0.5 & 1.5 but no red fault light or F code.
Tried switching off & on a final time, this time the F12 code and red light appeared once along with the red fault light for a few seconds the gauge continued to race up and down but the fan appeared to run constantly and not pulsing this time. All the time there was no ignition.
Checked all the pcb & interface connection but still no joy.
Spoke with glow worm they say pcb has probably failed, dont jump on me when i say i have no issue changing this component apologies to the gas engineers but times is hard.
I can either get glow worm to repair if its that part £285.00, or new which i install myself £155.00 or a refurbed pcb for £65.00 again install myself.
If it is the pcb thats failed would the digital display still show or maybe the user interface is up the wall?
just miffed by electronics, my back ground is building serivces & maintenance plumbing so happy to change the mechanical parts, even had my CCN1 a few years ago but thats another story, and advice on the above would be appreciated. Thanks in advance.
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15 Oct 2012
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United Kingdom
I'm not sure why glowworm even gave you any info on that fault, to change either the main pcb or the user interface you need to be an RGI as they both effect the combustion
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