My Potterton Suprima HE 60 is approaching 10 years old. A few years ago it went badly wrong because the metal flue had corroded (known design flaw) and condensate had dripped down through the boiler.
That was all fixed but every now and again it stops working. The programmer is on, the thermostat is calling for heat, the motorised valves have opened but the boiler is dead - no burner, no LEDs lit. And then half an hour later it springs into life as if nothing has happened.
A couple of engineers have looked at it but say there's nothing they can do when it's working - they need to see it when it's dead, but they never arrive quickly enough to see that.
So I'm thinking it's time for drastic action - my options would seem to be new PCB or new boiler. Given the former is likely to be considerably cheaper, is it worth trying, or is there a danger the fault is not on the PCB and it will be a waste of time?
One last wrinkle - this morning the heating was off but when I checked the boiler was showing an "Ignition" fault. However, resetting cleared it and it appeared to fire up just fine...
I don't know what the community is going to make of all this but any advice is much appreciated!