Yes they can be repaired... relatively easily...
Ener-Tech Electronics made the Printed circuit board - somebody else put the components on it (it may well have been Ener-Tech or outsourced) The Potterton Part Number is 407677 (Printed Circuit Board Assembly) - they can be repaired - here's a link to somebody repairing a 407677 on their Potterton Profile Boiler...
http://kaijaks.co.uk/blog/nick/2008/02/10/dodgy-old-boiler
Like many PCBs of this technology they can suffer from bad joints - the big weakness though is the Electrolytic Capacitors - they age and fail in warm environments and guess what? Boilers are warm environments.
The board also tends to suffer a resistor overheating (R15 I think) and I believe this is just a drain component to allow the gas valve to shut quickly - the resistor just acts as a shunt for back emf - I don't think that R15 is strictly necessary for the board to work - nice to have.
Ener-Tech was formed as a subsidiary of Birmid Qualcast in 1986. It was managed by Potterton to primarily design and manufacture electronic components for incorporation into Potterton boilers.
Baxi now own Potterton.
Good luck...
Peccavi
February 2010
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