I have a Lelit Diana (PL60T) double boiler machine. Aside from the scale issue I had in the first year (2018) of owning it, it's been a solid machine. I've been using rpavlis water for probably a year now. Yesterday, I decided I'd do my regular maintenance of a Cafiza backflush and a Rinza steam wand cleaning. I thought I'd also go ahead and Dezcal the machine, even though I've been using softened or rpavlis water ever since I had the machine professionally taken apart and descaled. When I removed the shower screen to clean it, the group head shower holder came out, which I had never removed before. Anyway, everything went back together just fine after cleaning it all, but since then, my shots are pulling differently.

What normally happens is the pump turns on as soon as I flip the brew switch and the machine usually runs at about 10 bars of pressure until the shot finishes. Now, I flip the switch and it goes up to 10 bars, but once the first drops start, which is usually around 3-4 seconds, the pump gets really quiet and the pressure drops to about 8 bars for 5-10 seconds and the espresso just drops out of the PF, then it kicks back up to 10 bars and the pump goes back to its normal sound. These shots take about 35-40 seconds for a 2:1 ratio with 18g in, 36 out, when they normally take 28-30. I'm noticing that with these shots, there are larger bubbles forming, and not the usual beautiful crema.

I haven't been able to find anyone talk about a similar situation. Hoping someone here has an idea of what it might be and what I might be able to try to fix it.

Thank you!
Mark

Have not used that machine. When your pressure drops, would it coincide with the heater cycling? I have seen pumps drag when the heater kicks in due to low power.

Hey cannonfodder, good question. I suppose anything is possible, but it's literally never happened before and it happened on the first few shots I pulled after cleaning the entire machine. Funny though, I get up this morning and pull a couple shots and it ran just fine. Weird... so I'll keep an eye on it to see if it keeps acting up, but right now it seems almost like it fixed itself. We'll see!

Mark

You could try lowering the OPV pressure to find exactly where your pump is stalling, but the pump is dying. You could replace the pump. or look the threads about rebuilding a vibe pump and try that, then replace it if it still stalls at less than 10 Bar.