how can i install a new circuitboardto potterton profile407677?

Comprehensive article here - words& pictures - pictures expand when clicked

http://kaijaks.co.uk/blog/nick/2008/02/10/dodgy-old-boiler

A digital photo before you remove the PCB will give you confidence but I doubt you will need to refer to it.

1) Turn off power
2) Remove lower cover - single screw underneath
3) Drop down hinged plate - single
4) Remove connections
5) Ease PCB off corner posts
6) Reverse order with new board

Peccavi
November 2010