I just upgraded to an Alex Duetto 2 and Vario combo. I received it Friday and had the weekend to play with it. I scoured the board but couldn't find any definitive answers to the following questions:

1. Does raising the lever half way pre-infuse the puck with line pressure? Or, is this taken care of automatically when the lever is raised all the way and the pump kicks in?

2. My brew pressure gauge reads a tad over 10 bar while brewing. I have about 2 bar of static pressure from my RO lines (plumbed in). Is this gauge accurate? Is the puck really seeing 10 bar pressure and should I adjust it down to 9?

Thanks for sharing!

Joel,

Congrats on the machine and grinder! You should have many years of hapiness with your setup.

On to your questions:
1. Yes, lifting the lever halfway up and allowing it to stay there will eventually pre-infuse the puck with 2 bar of line pressure. However, I say eventually because you first have to fill up the grouphead's pathways before the pressue will make it to the puck.

Lifting the lever all the way to engage the pump will still pre-infuse the puck with much lower pressure initially and will ramp up to the 10 bar you currently have set for the OPV at the 7 - 8 second point.

2. Yes, it sounds like you are indeed seeing 10 bar at the puck, which is not all that unusual. My QM Alexia shipped with the OPV set at 10 bar, which I lowered to 9. Feel free to adjust it to taste. It really is a personal preference thing.

Joel, congrats on your new setup. I too have the Duetto II and Vario combo. I have been using the Duetto for about a month and I am very pleased with it. Mine also came setup at 10 bar. I may try dropping it down to 9-9.5 but I have had great results at 10 so far.
The Vario is working great for me too. I also have a Mazzer Mini but use the Vario all the time.
I added Andreja water and steam wands to mine too. Have fun with the new machine.

The machine's gauge may not be that accurate, as on my Vetrano, 10 bar is really about 9.5. Before adjusting see what kind of results you get.

joel wrote:Is the puck really seeing 10 bar pressure and should I adjust it down to 9?

If you want to calibrate your machine with others, I suppose it matters. Otherwise I'm with Scott - try it as-is. Later try lowering/raising the brew pressure 1.0 bar and decide if it's better or worse. To put it another way (and with apologies to Greg Scace), precise measurements are great for calibrating identical equipment and for more meaningfully comparing notes with others, but developing the taste skills required to diagnose extraction issues is far more useful and costs less.

joel wrote: 1. Does raising the lever half way pre-infuse the puck with line pressure? Or, is this taken care of automatically when the lever is raised all the way and the pump kicks in?

E61 will always pre-infuse, so you should not really use the middle position. Because you have line pressure you can use it to pre-infuse even more, but probably that would cause only trouble.

2. My brew pressure gauge reads a tad over 10 bar while brewing. I have about 2 bar of static pressure from my RO lines (plumbed in). Is this gauge accurate? Is the puck really seeing 10 bar pressure and should I adjust it down to 9?

Because brew path is a dynamic system (water is flowing all the time), there is some loss due to pipes and gicleur. Probably the puck is seeing quite close to 10 bar. But that's not really bad and will be disappear to other sources of variation. My experience is that you should start worrying at something like 11-12 bar.

Thanks everyone. I am loving the combo. Soooo much less work than Silvia. I had grown accustomed to the routine I put Silvia and Rocky through for each milk drink and find myself looking for more things to do on my new setup. Miss Alex is a very, very nice machine and I am happy I decided to take the plunge. Also, the Vario is great compared to the Rocky. I've only put about 1.5 lbs through it since I received it Friday but no mess issues so far and the grind appears very consistent and mostly clump free (the few clumps it puts out break with just the slightest portafilter shake).

I will leave the brew pressure as is for now and adjust later. I was concerned it was causing channeling due to the drip pattern (looks like a donut shaped extraction at the beginning) and holes in the puck. Taste is fine though so maybe I will use it for a while then bring it down and try to taste a difference.

Don't know why I didn't think of this before but, to have myself a look at the pre-infusion with line pressure, I raised the brew lever 1/2 way without the portafilter inserted in to the group. Nothing came out. Water began to flow once I raised it the rest of the way but not in any other position. Is something wrong with my brew lever? Can someone confirm line pressure water flows from the group in the 1/2 raised position?

Thanks again!

joel wrote:I was concerned it was causing channeling due to the drip pattern (looks like a donut shaped extraction at the beginning) and holes in the puck.

I wouldn't worry too much about the puck's appearance. The brew chamber pressure goes from 9 bar to 0 in an instant, which could be the source of the "holes" you saw. My recommendation is simple: If the pucks look and feel basically the same each time, whether they be soggy, dry, sandy or smooth, you've exhausted the diagnosis value of puckology.

The donut extractions are another story. If the center fills in a second or two later, then move on, but if dead zones persist beyond the 10 second mark, that indicates a problem with you barista technique. The most likely causes are center-weighted distribution (see Stockfleths Move for Dummies) or rough handling/tapping breaking the puck/basket adhesion. You may also want to give nutation a try, though I'm only a recent convert.