Hi. I appreciate if you can you help me troubleshoot my La Pavoni pre millenium.

I have serviced it using in May and changed gaskets and all the small parts that used to be serviced. Since then it has worked fine up until now.

What is happening now is it feels like the water is boiling when it comes out into the group head and into the portafilter. It sounds also like the water is cooking and then water goes really fast through the portafilter. There is no cream being created like before but very bubbly coffee coming out of the portafiler instead. Also the group head feels much hotter then before.

Another observation is that the lever goes up by itself when the machine has almost cooled down.

These are all the symptoms and I suspect there must be something is not right with the gaskets. What thing can I check out to find out whats wrong with it?

Hi,

bortek wrote: Another observation is that the lever goes up by itself when the machine has almost cooled down

This probably just means the gaskets actually work well. As the grouphead, and steam therein, cools down there is suction on piston and thus the lever rises. On the post millennium machines the grouphead is filled with water and this phenomenon does not occur.

bortek wrote:What is happening now is it feels like the water is boiling when it comes out into the group head and into the portafilter. It sounds also like the water is cooking and then water goes really fast through the portafilter. There is no cream being created like before but very bubbly coffee coming out of the portafiler instead. Also the group head feels much hotter then before.

It would be useful to know the boiler pressure. I suppose you do not have the boiler pressure gauge? It could be that, if your machine has one, the pressure stat is goner and you'll need to replace it. When this happens the pressure can rise too high and thus you have too hot water. Another reason for the same phenomenon could be a blocked pressure stat tube, again if your machine has one. This can happen after descale as the dislodged particles find their way into the tube.

If the machine is without a pstat, it could have a blocked / non-functional over pressure valve. The one that should start hissing once the pressure is correct.

In general with these machines my advice is to always have a (digital) thermometer attached to the grouphead. And yeah, the boiler manometer does help diagnosing some of these issues.

Thanks for your valuable reply and explanation. Iam ordering a boiler gauges as we speak with some other service parts.

Will check the glass tube if it's clogged and excess pressure valve too.