[UPDATED POST] OK, since the first post of my schemtic I have updated this (original) post becasue the original image was too crap to be read properly. I have therefore improved this image and also added the other two PCBs that I came across and rev-eng'd. As you can see there are 3 different control boards of ever increasing complexitiy. I guess they've improved the design with the passage of time. I have therefore called them MKI, MKII & MKIII. This is just a naming convention that I alone have given them. Please note that although I have strived for accuracy please do NOT assume anything is indeed correct! I just hope someone can make use of it. These control PCBs are from a replacement kit #231711, the PCB number is 230260 and can be used to control Baxi Solo 2 PF / 3 PF / 3 PF Systems. Cheers, Andy ------------- MKI Schematic ------------- MKII Schematic PCB Board (Front and back). ------------- MKIII Schematic PCB Board (Front and back. Note Tracking view has been mirror imaged). PS. What a pain in the arse that was to do. For some reason the images uploaded to DIYNot are compressed (?) and as a result degraded. Hence the addition of the PhotoBucket links to better qualitiy images.