Why does my Potterton Profile 80el fire up intermittently?

I have just had the same fault on my 50E.

It fired occasionally or when I tapped the side of the boiler.
I found after removing the circuit board cover and tapping various components with insulated screwdriver, with the power on (Be very careful..)that the small transformer had seperated from the circuit board on 3 of the 4 legs.
I re-soldered them back onto the board and all is well..:))

Happy Days

Perko Snr...
February 2011

Potterton Profile - about 10years old - intermittent firing - pressure switch could be heard clicking in and out - so suspected the Controller board. Removed the 3 capacitors as per previous posts - they all looked OK and behaved like capacitors should when tested on a small multimeter - put them back, soldering carefully - same problem as before - so made the trip to Maplins - 2x 22uF 63v and one 4.7uF 63v - soldered them in instead and it works perfectly! Magic. The capacitors are obviously breaking down at the 50v circuit voltage - so a higher voltage rating would be a better long-life design solution. The resistor R15 between the relay and the pressure switch connector block was looking seriously overheated - so changed that as well. Black-brown-yellow = 100K-ohms, looks as tho' it may have 240 across it - so with i=E/R that makes 2.4mA or 567mW i.e. over 1/2 watt - no wonder the little 1/10 watt component looked frazzled. Its a pity these circuit designers don't do their job properly - or perhaps it is deliberate built-in obsolescence. If it was fitted to a Toyota, we'd have a global product recall and all get our money back.

Roger Forshaw, Romsey Hants
February 2010

It is likelyt that controlboard playing up but not sure.
it need to be tested when in fault why not working
test need to be in secquence

Mr K
November 2009