The boiler of a friend broke down last week and I got it up a running in a couple of evenings. The first to check everything and then to follow the fault diagnosis in the installation manual. The diagnosis was to replace the PCB (printed circuit board), which cost about £100+VAT. This was purchased the following day and that evening the PCB was replaced with the new one.
Once done it failed to fire although the PCB was working as the diagnosis changed slightly to the fact that the fan had stopped working. Once the internal elements of the fan had been spun round the boiler fired and has worked perfectly ever since (touch wood). This was a Prima F of about 10 years old.
If you have the installation manual it has a fault diagnosis table in the back. You will also need a voltage test meter.
Good luck
Dave Kildare
October 2006
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