cksaurus wrote:Looks like the discussion now has diverted from its original topic. Perhaps I should start a new one and make a more specific title for a more focused discussion.

Opps ..sorry...No need for you to start a new one...I'll start a new thread

Adjusting the OPV is a pretty simple process, but tinkering with the inards of any machine for the first time can be a bit nerve wracking.


Loosen the nut indicated by the blue arrow first. Righty tighty, lefty loosey does apply here. The nut should unscrew pushing towards the boiler. You only need to loosen it a little bit. Once it is loose you will be able to unscrew the nut indicated in red. Hold the "blue arrow" nut still while backing the "red arrow" nut out.

How far to back the second nut out is going differ from machine to machine. Some have only had to back it out half a turn while others report having to pull it back a full turn or more. There are several posts here on HB that you can search for on how to make a pressure gauge. This is something that will be needed to accurately adjust the pressure.
You could do a bit of your own testing. Back it out half a turn, and brew some shots. Rinse and repeat.
Of course there are still other factors here. Bean freshness, grind, distribution of grinds, and tamping.

As a side note i installed my PID kit last weekend and LOVE IT! Adjustable OPV, and PID have made my Silvia such a pleasure. My consistency has jumped through the roof, and the PID has cut my time down by at least 10 minutes. I brew 2 cappa's every morning.

Auber PID ftw! I bought the higher model, but the original for $149 would be plenty.

Thanks for the nice picture and detailed instructions! I tried to do the adjustment this morning but my wrench may be too thick to hold onto either one of the nut. From your description, looks like this is not as easy as what I expected. Anyway I will go get another wrench and try it out.

Not sure if a pressure gauge is worth it as I am going to use it to tune to the right pressure and then it is useless.

According to the user manual, the pressure nut should be turned counter-clockwise to reduce the pressure, right? Some other users also suggested turning it by a half. So I will try that and see what happens.

Installing a PID is probably my next task. Auber PID looks pretty good and I have asked them a few questions and got very quick reply. Did you get the pre-infusion model? How does it improve the taste of your espresso?

cksaurus - FYI, I installed an Auber PID on my machine. It comes with great detailed instructions and is very easy to install. I've had no issues with it. The only thing to be aware of is if you install it per the instructions it will likely interfere with removal of the steam wand. I don't have the pre-infusion model so I can't provide any feedback there.

I had good success using an end wrench. The actual "head" of wrench is narrower then an adjustable wrench or channel locks.

Just be sure to take it easy. It will take a little bit of force to loosen it, but keep in mind that you do not need to use gorilla strength to tighten or loose these nuts. Brass is a softer metal.

I have seen some users on CoffeeGeek asking to rent a pressure gauge from other users. If you can find a member in your area that has one, maybe you can do the same. If you lived in the States i would have been glad to lend you mine...

You are correct. The nut should be turned counter-clockwise to reduce. I did about half a turn at first, but then backed it out almost another half turn after pulling a couple of shots. I believe i am coming in at just under 9 bar right now. Though i am sure i will play with the setting some more in the future.

I do have the pre-infusion model. I am not sure if i can claim that the PID alone has given me better espresso, but it is still new to me. Consistency is what it is all about. For the past year i have found that i have been making up for Miss Silvia's lack of consistency by grinding finer, and tamping harder. The problem here is that i have only gotten great results maybe 25% of the time, and good results 50-75% of the time. High pressure leads to channeling no matter how good of a grinder you have, and ultimately leads to sink shots, or cappuccinos.

I have still been rather happy about the results, and I understood the shortcomings of this entry level machine when I bought it. I have found that some beans/roasts are a bit more resilient to shoddy technique/consistency when compared to others. I pulled quite a few good shots with Intelligentsia's Black Cat, but have found it a bit harder to get the same results out of Cafe Fresco's espresso blends (I have tried a few of their SO's, and had better results).

Changing up to the adjustable OPV, and the PID has really aided me in fine tuning the other problems, and sloppy technique i have, but could not prevent. I have only just started to use it, and have only used the SO Costa Rican that i had from Cafe Fresco thus far so only time will tell. But I can say for certain that the amount of channeling i have been getting has been dramatically reduced thus leading to better tasting shots.

There are two things the PID alone did for me. Temperature consistency, and has dramatically reduced the time it takes for me to pull two cappuccino's each morning. Couple those with the adjustable OPV, and they were well worth the $$

(I hope I didn't stray too far from topic)

-Donovan

Thanks Donovan! I have adjusted the OPV of my Silvia and posted another thread to share with the other new Silvia v3 users. Feel free to have a look.

http://www.home-barista.com/tips/adjust ... 11158.html

I find the taste now is less harsh but far from being "sweet", as commented by most Silvia users. Maybe I misunderstand the word sweet (I have to admit I can't tell whether an espresso is good or not). The after taste is also not as strong as before. Not sure if I am on the right track. Perhaps I still need a pressure gauge sooner or later.

Coffee beans I use are freshly roasted, usually within one or two weeks. The roaster runs his own cafe and makes beautiful coffee. I heard about Black Cat Espresso but the shipping charge is intimidating, plus it takes a while to get to here.

With so many people using PID, it is definitely worth installing that to improve the shot. I just feel a bit uncomfortable fiddling with wires as I am not mechanically inclined.

Temperature, grind, bean, and roast are all big factors in the final product. Some beans/roasts are more on the bittersweet chocolate end of the spectrum, but still can have sweetness to them. Others like some Ethiopian beans tend to be more fruity, and it is obviously easier to bring out sweeter flavors.

How long after you pulled that shot did you take that picture? The crema seems to have dissipated quite a bit in the photo. Depending on the time frame here you might have had excessive blonding. Could be a sign of either to light of a grind, or beans that are not up to par. How did the shot pull? What was the volume of the shot? Are you pulling a single or double? I never tried the Rancilio single basket, but i hear it is nearly impossible to pull a good shot with it.

Before i purchased the PID i had a feeling that i was pulling my shots at to high of a temp, and now know i have been. This is also half (if not more) the reason why i had better success with higher temp roasts...

The Auber instructions are very clear. They come on a CD, and include pictures to ensure that you only fiddle with the necessary wires. Of course if you do buy 1, and have problems installing it there are plenty here (myself included) that would be glad to answer any questions you might have.

-Donovan

Thanks for your advice on Auber PID. I guess I will try some more techniques and if they all fail, definitely need the PID and start over again.

I took that picture almost instantly when the pull is done. It is a double and takes 25 sec. After making the OPV adjustment, it seems the shot is a bit different from before, with the crema darker and a little more bubbles on top. I have bought a bottomless portafilter but haven't used it yet. It should be a good way to tell whether there is any problem with the dose, distribution or tamping. I will capture a video later and post it for comments.