Just looked at a temperature controlled fan for a friend. It refuses to work from scratch, but giving the blades a quick spin seems to trick it into starting.
Vague memories of capacitors prompted me to have a gander, where I found:
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It's marked "Italfarad" and my guess is it's the 2uF from their range. All the markings match their website
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Looking on eBay it seems the "RP2" version is available easily - and unless I am missing something it seems identical in specs.
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I guess for £7.00 it's worth a punt ...