La Pavoni Europiccola (pre millenium) switch not lighting up

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
chuu

#1: Post by chuu »

I've been working to restore a La Pavoni Europiccola, seemingly from the 90's. Right now I'm having issues with the power switch not lighting up, even though the machine does heat up. Another problem seems to be with the pressure sensor, according to the pressure meter on top of the water tank the pressure seems to be climbing up and over 1 bar, ultimately triggering the pressure valve.

I already tried buying a new power switch, but that doesn't solve the problem with the light not working. I'd assume that the two lights in the switch operate independently of each other, so having two faulty lights in a single new switch seems unlikely?

Since the problem is electrical, I've tried to figure out if there's something wrong with the wiring. Based on this: http://www.francescoceccarelli.eu/lapav ... mi_eng.htm, it seems like I'd have the 1990-1995 model (the original switch was similar to that one too), though my pressure sensor seems to be similar to the 1996-2003 model.

I tried wiring up everything exactly like in the 1990-1995 reference picture, but the machine doesn't even power on. The original way it was wired is as in the picture below (the two wires on the left are switched, when compared to mine and the reference photo).

So I guess my questions are: any clue what's making the light specifically not work, when the heating element has no problems working? Why does my wiring seem to differ from what the reference has? Any other reference photos I could follow?
I still need to check that the tube to the pressure sensor is open before asking more questions about why the pressure keeps on building up.


chuu (original poster)

#2: Post by chuu (original poster) »

After opening up the pressure sensor pipe and cleaning it, the pressure problems I've had got fixed. Now the machine functions as it should, and the green light seems to work after the pressure starts building up for the second time (the red light doesn't light up at all). It doesn't really make sense to me, but now that everything works, I'm going to start worrying about brewing instead of maintenance!

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homeburrero
Team HB

#3: Post by homeburrero »

chuu wrote:Now the machine functions as it should, and the green light seems to work after the pressure starts building up for the second time (the red light doesn't light up at all).
That's a common problem, and the original machine may have been shipped with that flaw. It also would have that flaw if you rewired machine per the one pictured in Francesco Ceccarelli's example wiring for the 90-95 models here.

Francesco describes this and the solution on this page: http://www.francescoceccarelli.eu/lapav ... ri_eng.htm

Below is another wiring diagram for this type of machine that may be useful. Yours differs from this one in that your neutral (blue wire on your cord) goes directly to the switch instead of the line wire (brown wire on your cord.) It will work fine either way, but on machines that have a polarized power cord it's arguably best from a fail safety standpoint to wire it so that the line wire is the one that goes to that pin #2 on the switch. Note the wire going from the pStat to pin 3 of the switch -- that's the one you are missing and is needed to make your red switch lamp come on.

Pat
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