My first post here and I'm a total newbie, as in, I haven't owned *any* machine except for an old stovetop years ago. But I drink espresso enough that I decided to jump in the deeper end of the pool and went after a Cremina. The one I have appears to be in excellent condition but there seems to be a problem-- water doesn't seem to flow through the group head!

Am I missing something obvious? I also tried searching HB but in case I missed a previous post that's similar, please help me out.



Thanks for any help!
Tito

Hi Tito - List of possibilities:

Plugged siphon tube
Blocked/plugged dispersion screen
piston unscrewed from piston rod
missing siphon tube

All are easy to diagnose - look into the top of the boiler using a flashlight, look for scale, and for the presence of the tube. Remove the dispersion screen & see if it's plugged, and/or if the piston falls out! Citric acid will take care of scale, and coffee cleaner will take care of the screen. Nice looking machine, but as they say...no water...no coffee!

Thanks for the tips, Doug, the siphon is there so the list is down to three.



If it's a plugged tube, I'll be getting the citric acid you've shipped me this week so that'll solve that but I do need to get some Joe Glo.

Then I'll try my luck with removing the snap rings without removing the group head. I watched your "So You Got a Cremina Video #2" where you removed the group head before removing the piston and dispersion screen but I'm considering doing the shortcut shown here (~56 secs in):



Thanks again and Happy Thanksgiving!

My first post here and I'm a total newbie . . .

Well, you said it but your words and actions do not necessarily reflect that. But anyway, I'll ask it - you are letting this machine warm up for ~30 minutes and bleeding off any "false pressure" at about the 10 minute mark?

Well, you said it but your words and actions do not necessarily reflect that.

Thanks, Eric, I'll take that as a compliment The past month or so, I'd spent many sleepless nights catching up and it's a testament to the sharing and depth of knowledge of you guys here that's making me "sound" experienced. Before this Cremina, my only coffee gear were an Aeropress and (slightly embarrassed to admit) a Cuisinart burr grinder. I do have an OE Pharos on the way but am not in a rush to master things. I do enjoy the learning part as much as the drinking part

But anyway, I'll ask it - you are letting this machine warm up for ~30 minutes and bleeding off any "false pressure" at about the 10 minute mark?

Yes, I did that last night. Thanks!

Oh boy, this is turning out to be a bit of an adventure

Yesterday I disassembled my Cremina's group, removed the siphon, piston and dispersion screen. The siphon wasn't blocked and I soaked it in citric acid to remove a bit of scaling; the dispersion screen was totally gunked up so I soaked that and the group head overnight in Joe Glo.



Today I reassembled the group, lubed the piston chamber, installed the yoke (only to find out I'd installed it the wrong way, argh, quickly reinstalled), put in the dispersion screen and tested the suction (from OE's SYGAC video #14/15). Basically, using just the group, if I pull on the lever with the screen by my palm, I feel good suction. If I push on the lever while covering the siphon hole with my thumb, I also feel suction.

After reassembly, the moment of truth-- still no joy If I pull the lever up, there is some kind of reverse pressure (vacuum) that pulls it down by itself. I noticed this even before disassembly but thought that was just the blocked screen.



What I don't understand is that the hole leading to the siphon is way up inside the chamber behind the piston's "plunger" (see diagram below). Since the piston seals are snug fit inside the chamber, how does water get from that upper chamber to the lower chamber? I seem to be missing something quite obvious



Thanks for any help!

TitoM wrote:What I don't understand is that the hole leading to the siphon is way up inside the chamber behind the piston's "plunger" (see diagram below). Since the piston seals are snug fit inside the chamber, how does water get from that upper chamber to the lower chamber? I seem to be missing something quite obvious

Your handwritten hydraulic schematic is not correct -- well, it's incomplete, actually. Here's the Olympia schematic.



There is always water and pressure above the piston, and it is therefore normal for boiler pressure to force the piston down if it is raised without coffee in the portafilter. Water, however, fills the group through the lower hole after the piston is raised. With the piston removed raised or removed, the lower hole should be visible as a small hole in the side wall of the group. While I have no personal experience with this happening, it is at least theoretically possible for the lower hole to be plugged and the upper passage to remain open; that would allow the area above the piston to be pressurized but still not allow water into the group.

Tito,

With what you've rules out, it seems as though the inlet hole in the grouphead is blocked. I take it you checked to ensure your piston is screwed on all the way?

Below are picture that will show you what your piston should look like when the lever is all the way down and one with it all the way up to expose the inlet hole. if you don't see this, something is definitely wrong.


This is a view with the lever all the way down. The piston should leave just a tiny bit of the sleeve showing.


This is a view with the lever lifted all the way up. Notice the little hole below the bottom of the piston. That is the inlet from the siphon tube. If you do not see this, something is wrong.

Hope these help to find the culprit.

That's what I missed! Thanks Richard and Merle, the inlet hole was indeed scaled over and blocked. A little citric unblocked it and it works fine now!



Thanks too Doug and Barb for your excellent videos. Without those, I wouldn't think of making an attempt.

TitoM wrote:. . . the inlet hole was indeed scaled over and blocked. A little citric unblocked it and it works fine now!

Great! Glad it was a simple thing.