Londinium 1 extraction issues - Page 6

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Markant

Postby Markant » Dec 06, 2018, 7:55 pm

LObin wrote:I will definitely measure temp in the cup tonight. I did read about TS stall and always flush after a shot. I also tried a half a second flush prior to locking in the PF.
I have left my machine on for anywhere between 16 and 48hrs. Never less...

I do however hear a little water sound that seems to be coming from the TS. Not sure if it should be silent or not. I bleed the air of the TS twice but it's still there. Thought it might be the water cycling in the TS that I'm hearing...
Maybe someone with an L1 can comment on this?


There should be no sound; if you have that "water bubbling sound' then you got some air in the TS. You shouldn't have this happening if you start from cold, and flush a little (almost immediately) after each shot. Easiest way (imo, ymmv) to get rid of it is to switch the machine off; let pressure go to zero (steam tap) and fire it up again. Long flushing should also help, but I 've got mixed results with that.

By the way, one hour is more than enough to get a stable group temperature, so 16-48 hours won't help much.

About your problem: temperature too low, might be it. Easy to find out: crank up the pressurestat to say 1.4 bar. The temperature of the group will go up, (even if the TS is partially blocked).

Hmmmm, just a thought: are you sure that there is no restrictor in the TS in your machine?? Reiss used to sell them to make the TS less effective, meaning to make the group temperature lower....

And last remark, is the portafilter heating up with the group? Or are you using it 'cold' ? ( in my experience this has effect on the taste of the espresso (lower group temperature of course) however usually not to that extent that it becomes undrinkable).

On the Londinium website under support you can find a description of a user modification how to plumb in with the HX being cold fed: meaning you could pre infuse at a higher pressure than the boiler pressure.

Pino

Postby Pino » Dec 06, 2018, 8:15 pm

Markant wrote:On the Londinium website under support you can find a description of a user modification how to plump in with the HX being cold fed: meaning you could pre infuse at a higher pressure than the boiler pressure.

Good information But this is a L1 that is no HX no cold feed (except to the boiler)no pre infusion adjustment other than the boiler temp.

Markant

Postby Markant » Dec 07, 2018, 6:39 am

Pino wrote:Good information But this is a L1 that is no HX no cold feed (except to the boiler)no pre infusion adjustment other than the boiler temp.


Yes, I know except: An original L1 v1.0 has a horizontal HX that is fed from the boiler. That mod makes it into a plumbed-in cold fed HX. So the following is not exactly true anymore (and that's why I put it there):

LObin wrote:....plumbing in the L1 does not allow for a different PI pressure. It will always preinfuse at boiler pressure. Plumbing in the L1 only allows to bypass the vibe pump for the auto-refill.



Funny enough, Reiss originally claimed that an L1 cold fed would never ever work ..... And now take a close look at the architecture of Londinium R..... which is in fact cold fed from the watertank!.... :-)) Now with pre-infusion under control, a good change, I would say. (being tempted to change the architecture of my L1 into that of an LR; it shouldn't be that hard).

LObin

Postby LObin » Dec 07, 2018, 9:06 am

Markant wrote:There should be no sound; if you have that "water bubbling sound' then you got some air in the TS. You shouldn't have this happening if you start from cold, and flush a little (almost immediately) after each shot. Easiest way (imo, ymmv) to get rid of it is to switch the machine off; let pressure go to zero (steam tap) and fire it up again. Long flushing should also help, but I 've got mixed results with that.

By the way, one hour is more than enough to get a stable group temperature, so 16-48 hours won't help much.

About your problem: temperature too low, might be it. Easy to find out: crank up the pressurestat to say 1.4 bar. The temperature of the group will go up, (even if the TS is partially blocked).

Hmmmm, just a thought: are you sure that there is no restrictor in the TS in your machine?? Reiss used to sell them to make the TS less effective, meaning to make the group temperature lower....

And last remark, is the portafilter heating up with the group? Or are you using it 'cold' ? ( in my experience this has effect on the taste of the espresso (lower group temperature of course) however usually not to that extent that it becomes undrinkable).

On the Londinium website under support you can find a description of a user modification how to plumb in with the HX being cold fed: meaning you could pre infuse at a higher pressure than the boiler pressure.


Thanks for your imput.

A few things I wanna set straight though...

I don't let the machine warmup for 16 to 48 hrs. This is the average time I leave my L1 on for...
I was just eliminating the cold system based on the assumption that my warmup time wasn't long enough.

I'm in the middle of disassembling the TS since it's most likely blocked. Reiss is helping me out in the process.

Once I have a working L1, I might consider the cold fed L1 mod. Found the thread a few weeks back and thought it was exactly what I would wanna do if I was to plumb in my L1.

My L1 is running way too cold (so far no restrictor found) and this is answer I was seeking when I (very actively) was asking why I was getting such poor and CONSISTENT results.

I will report back. Cheers!

User avatar
zix

Postby zix » Dec 07, 2018, 10:28 am

Good luck! Being another (very happy) Bezzera B3000AL user I am very interested in seeing what the solution turns out to be for your Londinium L1, and how you find it to be in use compared to the Bez - when the L1 works again.
LMWDP #047

LObin

Postby LObin » replying to zix » Dec 07, 2018, 10:57 am

Isn't the B3000AL an amazing machine or what!!
We just had our kitchen redone and the Bezzera is just a tad big for it. The wife kept commenting on how we need an opened/closed sign on the front door with a machine like this! ;)
If I had a dedicated coffee bar or even a tad bigger and more opened kitchen, this whole thread would've never existed... Sadly now she's waiting for her next owner (and a bigger kitchen)...

Once my L1 is up and running I'll definitely share my thoughts. Cheers!

Pino

Postby Pino » Dec 07, 2018, 11:51 am

[quote="Markant"]Yes, I know except: An original L1 v1.0 has a horizontal HX that is fed from the boiler. That mod makes it into a plumbed-in cold fed HX. So the following is not exactly true anymore (and that's why I put it there):

Ah, yes , thanks Markant for the reminder.
Image
However I only know mine was 'original 1st Generation L1. Yet how would I know if mine has this configuration? I'm not aware of a plate with Month/Year of manufacture.

User avatar
NelisB

Postby NelisB » Dec 07, 2018, 5:48 pm

Pino wrote:


Off topic:
About the drawing, the direction of the flow, how is this possible with the upper output of the bolier above water level? How does the upper output get water?

User avatar
Jake_G

Postby Jake_G » replying to NelisB » Dec 07, 2018, 9:02 pm

Boiler pressure forces water through the HX injector when the lever is lowered. When the lever is raised, the HX is sealed and the injector supply port on the boiler flooded, so the T'S circuit stays full. Lowering the lever with the boiler cold (no pressure) would indeed drain the HX down to boiler water level and introduce air.

Cheers!

- Jake

mathof

Postby mathof » Dec 08, 2018, 5:21 am

The sketch of thermosyphon flow in the group is, I believe, a pre-production drawing that Reiss posted to give an idea of what he was planning for the Londinium. As realised, there were, of course, changes. For example, the HX path in the boiler is no longer vertical. I've been wondering if the flow remained as in the image, which shows a water-jacket running from top to bottom of the group, or like this:

Image