Lelit Elizabeth pressure spiking/inconsistent

Pygmalion Here is a simple experiment you could try.

Done!

The temperature was at 96C because it was on at the end of the heat up cycle towards 93C. For the sake of the experiment, on the subsequent shot, I have set the temp to 96C, let it get here and set it back to 93C.

On the subsequent shot, I emptied the blind basket before starting, so both are from the same starting point. They were taken approx. 7 minutes apart. I also did one with the basket full of water, and the behaviour is the same overall, with the exception that, as expected, it reaches the target pressure faster.

When using coffee rather than the blind basket, the behaviour is the same, but the pressure gradually goes down to approx. 8.75 bar on the dial over the course of 35 seconds, as expected.

From cold:

7 minutes later:

This is an older video where it shows a coffee pour. This was when the Elizabeth’s pressure was set at 10 bar. But you can see the behaviour of the gradual pressure reduction. These days is the same, but at 9 bar or thereabouts.

With coffee (older video):

Hope the above is helpful.

I pulled a shot with no PI, it went to 11 bar then gradually decreased to approximately 9.5 until the end of the shot. I filled the blind basket to the brim with cold water and hit button 1 again (no PI), it went up to 11 bar and stayed there until I stopped the shot. Is it that the opv is tuned to 11 bar (in my case here) and simply reduces as the puck gets extracted? I don’t see an issue really or is this different to the OP’s issue? I had noticed this recently but didn’t worry, as the coffee still tasting great

JahLaza pulled a shot with no PI, it went to 11 bar then gradually decreased to approximately 9.5 until the end of the shot. I filled the blind basket to the brim with cold water and hit button 1 again (no PI), it went up to 11 bar and stayed there until I stopped the shot. Is it that the opv is tuned to 11 bar (in my case here) and simply reduces as the puck gets extracted?

If this is the consistent behaviour, it could indeed be that your expansion valve pressure needs reducing, try reducing it to 9.5 bar against a blind filter and see how you get on.

JahLaza - what you are describing is absolutely normal and it is what you see on my videos, albeit at a lower pressure.

It’s not, however, what @Del_UK and Pygmalion are experiencing.

Yeah, ok, thanks both. I wonder if there’s any need to reduce it at all? I had read somewhere the difference between 9 and 10 bar isn’t worth talking about would you advise to reduce it a bar or so in my case?

JahLaza would you advise to reduce it a bar or so in my case?

Try it, it’s very easy. Only your taste buds will tell. 😊

Pygmalion out of curiosity, what water do you guys feed your machine with?

Reduced it to 9.5bar with blind filter (yes it was a very easy action!) just pulled a shot, it still went up to 10.5 bar at start of shot but maintained about 9.5 bar from about 13 secs. Tastes great, not sure if there’s a difference, fuller body I think maybe. Apologies if I’ve slightly diverged from the thread topic folks, interesting all the same🤔

Pygmalion I think I have the same issue as yourself. When I run first cycle with blind basket it hits 11 bar before slowly falling down towards 9.

Subsequent cycles go straight to 9 and hold. I tried filling the basket with cold water and that one goes straight to 9 bar and holds there.

I will pay attention to tomorrow mornings shots to see what is happening with coffee in the basket. I never look at the needle - watch start of shot then fill my milk jug whilst it’s pouring.

Pygmalion If I leave my machine for a while, fill blind basket with cold water - it overshoots to between 10 - 11 and slowly drops from there.

Everything following this first one goes straight to 9 and stays there.

If this is normal then grand. But it does seem very similar to what your videos were showing

Curiosity got the better of me and turned machine back on to pull couple of shots with coffee.

First one touches 10.5 bar when machine ramps up (no PI) and is just under 9 at the end of the shot.

Second shot made straight after only goes to 9 before beginning to drop down to 8 by end of shot. This was 2 secs slower than first one.

So consistent with what was happening with blind basket tests.

Something to be concerned about?

I do struggle to dial in a lot of the time and get consistent shots that take same time etc.. I always just put it down to my inexperience or some other reason however …

After reducing opv to give 9.5 bar in blind basket yesterday, I pulled first shot this morning, it went up just past 11 bar and then back to 9.5/10 bar during shot. I adjusted the opv again to give 9.5 bar using blind basket. Pulled a shot of coffee it shot to 10 bar then finished out around 9/just over 9 bar. Could it be these OPVs loose their adjustment? I’m no authority on them but looks like something like that maybe in this case? Not hugely upset the coffee is great but as others have stated if there’s a defect/sign of defect it’s still in warranty!

Plumbers silicone grease…as this is only a test, one I can’t actually do. Molykote 111 would be the ideal.

Yes, those points.