La Marzocco Linea AV timer randomly changing every 20 shots

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
coffee907

#1: Post by coffee907 »

Hi
I have a 2010 LaMarzocco linea AV 3 group. Every 20 or so shots the volumetric timer will drop down to say 15 seconds or jump up to say 45 seconds. We then reprogram it and its good to go for another 20 or so shots.

Any idea whats causing this ? Its just the one group head,the others work fine.

Also is there a trouble shooting manual ? or repair guide for this machine ? maybe a post or site that list things I should change out to upgrade it ?
thank you for your help