Glow Worm Sxi 30?

I'd be grateful for any help. I have a Glow Worm sxi 30 boiler. It is about 2 and a half years old.

Recently it has been coming up with an F13 error, which according to the user manual is a PCB fault.

When I switch the boiler off and switch on again, it works fine.

I intend to check the connections, and if all seems well then I understand I will need a new PCB.

Is there any reason I shouldn't take the cover off with the power supply to the boiler switched off to check the connections?

If the connections to the PCB are ok, is there any reason I shouldn't just go ahead and replace the PCB?

Thanks for any help