Hello everyone,

 

So I came across a Rancilio AT at the roaster I do service work for and I decided to play with it some and restore it having heard good things about the espresso quality.  I also happen to have an arsenal of old parts from a tech we bought out when he retired.

 

anyways I got the groups rebuilt and everything works just fine but I was wondering what some of you think about these machines, I know they waist A LOT of water, (about a quart per shot go's down the drain) but I also noticed the pressure for the group is really high, when I put my pressure gauge on the group it burried the needle! That's over 20 bars! don't worry I put a valve on the bottom of the pressure gauge to be able to relieve the pressure. I did the same thing on a Rancilio Lever and it capped out at 12 bars. The biggest problem I am having with the AT is there is so much pressure at the group it's leaking around the portafilter and I put brand new gaskets on it with no luck. 

 

So what are your thoughts and tips on this machine, is there a way to fine tune it? I realize I'm kinda at a loss and have no idea where to go from here.

 

Thanks Mat

Views: 515

Reply to This

Replies to This Discussion

So maybe a line pressure reducer is in order? Dropping it to 2 bars ought to do...

 

Need to refresh my browser more often, didn't mean to repeat.

Ah Ha!  Thank you!  I didn't think about that.  Maybe that tube you were talking about at the bottom of the group will help split off the pressure.  Otherwise it would be the pressure reducer like a lever machine uses and that Brady and Keith have pointed to.

Mathew said:

pure physics! the surface area of the diaphragm is about 5x the size of the the surface area of the piston and the line pressure is about 5 bars so 5x5=25bars. That's not the precise math because I don't have the parts in front of me to measure the size for sure but there is where the pressure comes from. 

 

Reply to Discussion

RSS

Barista Exchange Partners

Barista Exchange Friends

Keep Barista Exchange Free

Are you enjoying Barista Exchange? Is it helping you promote your business and helping you network in this great industry? Donate today to keep it free to all members. Supporters can join the "Supporters Group" with a donation. Thanks!

Clicky Web Analytics

© 2024   Created by Matt Milletto.   Powered by

Badges  |  Report an Issue  |  Terms of Service