Howdy everyone. I've been reading posts from this site for a while, and I'm excited to finally be contributing Unfortunately, my first contribution is a request for information (I'll try not to be such a leech in the future). At any rate, thanks in advance for the help.

So I recently bit the bullet and purchased my first espresso machine and grinder: Baratza Vario and a Rocket Cellini Premium Plus v2. Both are amazing products! The build quality on the Rocket is astounding...for all its many parts, the thing feels like a solid mass. When you move it, there is no indication that anything is wobbling or loose inside.

However impressive build quality aside, it did not come correctly calibrated. When I fired it up, my first several shots were sour to say the least. After ensuring that warm-up time was adequate (> 1 hour), and that my beans weren't bad, I noticed that the manometer was indicating a boiler pressure maxing at about .8 bar. I went in and adjusted the pressure to about 1.2 bar; the sourness was gone.

That brought my attention to the manometer for the brew pressure. This was reading 5-6 bar during extraction, 8 bar after about 10 seconds with a blind. At first I thought that the manometer was probably not reading correctly, I mean this was a brand new machine. The espresso wasn't bad, but shots were going blonde pretty quick (usually after less than 15 seconds with a shot dialed for a 1oz - 25 second pull). I wound up dark-stopping a lot of my shots to avoid watery-ness.

At this point, I'm wondering if the brew-pressure manometer is actually correct. So I open up my machine again and tighten up the OPV using the blind basket and built in manometer to calibrate. A single turn didn't get me very far, and with the OPV completely closed, I was only up to a 7.5 bar brew pressure and 9.5 bar blind (after 10 seconds). I backed off the OPV a bit, and currently my manometer indicates that I'm brewing at 7 bar. The quality in the espresso is VASTLY improved from my original brews at 5-6 bar - fuller mouth feel, sweeter taste, better all around extraction (imagine that, dark-stop no longer required). That said, it's still not where I want it to be. I would like more pressure, but the OPV is almost fully tightened.

So now the question: Is this a pump problem? A build problem? OPV problem? This thing weighs like 50 pounds and being in Florida, I'd really prefer not to pay shipping to send it back to Washington state for an exchange if I can just fix it on my own. So is there a way for me to get my brew pressure up above 8 bar (8.5 would be perfect for me)?

Again, thanks in advance for the insight!

I would suggest you take your boiler pressure down to 1.10 bar MAX on a fully warmed up machine. As regard the brew pressure, see this:
OPV on Rocket Cellini V2 is confusing.

Thanks for the reply, Eric! The article you refer to was the one that led to my learning how to adjust the OPV for my machine. Unfortunately as I stated in my longwinded post (sorry about that), I have already adjusted the OPV to maximum. In other words, it tightened the valve until it wouldn't tighten any more. This only took my brew pressure up to 7.5 bar. I since backed it off as I didn't like the idea of having it fully tightened.

Thanks for the suggestion, but that particular path has been traveled and led to a dead-end.

Well . . . OK . . . but your original post does not mention that you closed the ball valve while adjusting the OPV.

This ball valve needs to be closed while adjusting and opened for normal machine operation.

Yep. Missed the bit on the ball valve which remained in its original position (and is still in original position) throughout the adjustment of the OPV. Alright, so here's my question now: what do I do? Should I try to return the machine to it's original state, then close the ball valve and go from there?

The way I'm reading your reply, the ball valve takes the OPV out of the equation, removing the OPV as a "safety feature" so to speak so that the brew head gets the pressure straight from the boiler. So...I should turn the ball valve off and see if the machine hits 9 bar, correct?

Last question, and it's a dumb one...which way do I turn the ball valve to close it? With all the pipes coming and going, "lefty loosie" seems a bit confused.

Thank you in advance for reading my posts and answering my inept questions. Your advice is very much appreciated!

Maybe open up the OPV 1 full turn from where you have it now. Close the ball valve (I seem to remember it only turns one way) and see what pressure you have with the blind filter. The ball valve (by design) is closed when the handle is turned 90 degrees.

The ball valve closure just takes the other relief valve out of play.

I'm not going to have time to tinker this evening as I have plans for the holiday, but I'm very excited to give this a try tomorrow. Once I close the ball valve and test the pressure with the blind, how do I get that pressure with the ball valve open? Or basically, do I just leave it closed and be happy with my 9 bars? What's the next step assuming that all goes to plan?

I'll check in tonight (when the wife's not watching) and let you know how it goes tomorrow. Thanks again for the help, Eric! You are awesome!

Or basically, do I just leave it closed and be happy with my 9 bars?

No . . . correct operation is with the valve open. Adjust your grind and/or dose to achieve the desired pressure at the desired flow.