i have had a frustrating intermittent problem with my 5 year old potterton suprima 40 boiler it cuts out every preston guild! will take the pcb out and check and repair the dry joints as required . i've been playing around with it for i wile. right to the point i have been a car mechanic/ technician for 25 years any joker can buy a set of brakes for a bmw m3 and fit them without registration and could put them in wrong possibly causing a major accident, crazy isn't it?!very good web site loads of good tips.