# La Pavoni - when does the water come into the group?



## ejulia (Jan 13, 2017)

Dear La Pavoni fellows,

this is a more geeky question, but I am really curious about the details of the "plumbing" and trust some of you may have more insight than me so far. I understand that hot water and/or steam comes from the boiler through a pipe and then a little hole into the group. *But when does that happen, before or after the lever is in its top position? *If the water comes into the top part of the group while the piston is still in the low position, how does it get past the piston down to the basket with the coffee? If the water comes in only once it is in the top position, what did stop it from coming in before? (And then I shouldn't have had the early flow problems I mentioned in the earlier post.) I have been studying the technical drawings, which do a great job tell you where all the gaskets and pieces go, but unfortunately I can't yet infer from the how and when the water flows.

I have been thinking about these questions at night in my sleep, so I guess I really want to know this...

Any hints? I would be very grateful for any thoughts on this, including partial answers or more questions or suggestions for experiments that may also help figuring this out...


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## coffeechap (Apr 5, 2012)

The piston and seals are at such a length that when the piston is in the low position, the port that the water flow through from the boiler is blocked, preventing water getting into the group. When you raise the lever the piston moves clear of the port and allows water into the group.


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## RDC8 (Dec 6, 2016)

I found the following diagram showing the inner workings of the la pavoni. See how the water is forced up to the group head through a pipe from the bottom of the boiler unit. A coffeechap says, with the lever down the flow of water is blocked; when the lever is up the port is open and the pressure from the boiler forces the water up and into the group head.


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## GCGlasgow (Jul 27, 2014)

When you pull the lever up you can feel the point where water flows into the grouphead.


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