I paid out a good whack for a new boiler / heating system which was fitted in July – all the work was very neat and there’s no sign of any short cuts.

The boiler is a brand new Vaillant – 2 months in the printed circuit board has failed so it’s dead as a dodo.

What’s the best course of action?

– hit it very hard with a hammer to teach it a good lesson
– allow the plumber who supplied it to replace the pcb
– assume the whole boiler is likely to be a king size pain in the a55 and will almost certainly break down again and insist on a new one using the Comsumer Rights Act or similar?

What’s a reasonable course of action?

allow the plumber who supplied it to replace the pcb

This.

Although it’s not so much “allow” seeing as its
Almost certain the fault is nothing to do with him.

Hit it with a hammer, that’s always the best option, bigger the hammer the more chance it will work first time too, if not give it another one a little bit harder.

curious whos diagnosed the PCB as being dead ….

surely if the boiler stops workimg after a short period then youd go to the installer and ask why ….

Aye, call installer and let him do his bit.

Contact the installer, get him to contact group service. Theyll be out same day/next day.

Out of curiosity, did the death happen around the time of any thunder storms? We had one the other year and it fried all the outside lights. Must have been a big mains surge as all the PCBs had burn marks on them around the rectifying diodes….

Vaillant have a minimum 2 year warranty. If installed properly and Vaillant are informed by the fitter (which should happen) you get all your building regs cert and warranty emailed through.

So, should simply be a case of getting it fixed under warranty.

Note I’ve just had a new Vaillant (4 weeks ago or so)fitted hence how I know.

PCB on our Veissmann boiler failed in the first few weeks – replaced under warranty, everything has been fine since.

A %age of any part wil fail early. Has no bearing on the rest of the boiler.

If you bought one with a decent warranty ie 7 to 10 years, and follow the t&C’s of the warranty, then you’ve no worries tbh. phone the installer up and let him deal with it.
Like above, I had a similar experience with a Samsung induction hob, went pop almost as soon as installed, Samsung engineer came out immediately and replaced all the internals even tho it was just one part that had blown due to factory assembly fault.