Hi
I have just fixed a similar fault on my Potterton Netaheat 10-16 Electronic boiler. The symptoms were as follows. The fan would start and after about 5 seconds would then shut off. I suspected the pressure switch. This did turn out to be a bit iffy but was not the cause of this fault. I removed the pcb by squashing the plastic fixings in each corner of the pcb. As I turned over the pcb I saw straight away that there was a burnt out solder joint on the board. I cleaned it up and then re-soldered it. Hey presto I now have a working boiler again.
I could also smell burning around the pcb, it was very distinctive.
Check out www.cetltd.com/default.asp?id=154
This link is for the Electronic model which it sounds like yours is.
Hope this info helps.
By the way, these are dangerous boilers if you do not refit the main case properly. Carbon Monoxide can leak as it is a pressurised case.
Tim
November 2005
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