Recent content by Poincare

The 100uF caps arrived today. Relay buzzing merrily away when I got in from work. Replaced all 3, turned the power back on, and not even a single buzz. Eerie silence! It's golden! Poincare is back to his maths now until the boiler strikes again. Agile - thanks, I reckon you were...

The relay next to cap d in the pic is the one buzzing. It only buzzes when the boiler has been idle for a while e.g. during night. I haven't replaced the 100uF caps (3 of them) yet, though have ordered some. In fact when they arrive and I fit these three I will have replaced all the caps. It'll...

if 150GBP is no object I would agree. 50p for a capacitor or 3GBP for a relay makes faffing quite rewarding. Agile, you say "Without seeing the PCB I don't know!" Any chance you can see it in the pic? a,b,c, or d or another?. The biggest Barrel Capac is 100uF.

Appreciation of username choice. Ta. I replaced any suspect capacitors. If the smoothing capacitor is the one nearest the relay then no I didn't replace it as it looks OK. However I will do it as well. I take it the smoothing capacitor is the nearest?

Identical symptoms in my 50FF pcb. Saw a couple of capacitors looking a bit "old". One with bulge, one discoloured. Replaced both to no effect on the buzz. Then replaced the relay with identical one. For three days, the boiler worked without any buzz and I felt very pleased. Whilst putting...