Mine clicks when it opens, I can't hear it when it is holding open, and I can't even hear it when it goes closed.
I'd like to say again for anyone who has not read the entire thread- Make sure you use two switches in series (wire one to the next one, then wire both to the solenoid and cord as shown.)
Over the last year, a snail has caused my single float to stick closed three times. Each time I've caught it before it caused problems, because I have the ball-valve upstream set to just a drip. It has to stick open for almost a day before it adds more than an 1" to the sump.
I keep telling myself that I've got to fix it, but have not made time yet. Maybe this weekend.
Zeph