Combi boiler kettling

[PotterG]

We have a Potterton Combi boiler, it was losing pressure. Engineer replaced the diverter valve and said it was corroded. It worked fine for a few days before making a loud banging noise for s few minutes which stopped when the sink taps were on. It was ok for a couple of days and then went off completely. The engineer says the circuit board needs replacing but I'm wondering what caused the issue with the circuit board & whether it will just blow again. I think the boiler is about 8 years old. Any advice welcome.

 

[ShaunCorbs]

I would get a second opinion