Here is a little more information about the situation. After speaking with a highly-respected coffee peer of mine, we realized there could be more to the story.
1. When I turn on a group, the pressure gauge slowly wanders fron 8 to 10 bar and back. If I turn on one of the bar faucets while the group is on, the pressure will jump all over.
2. Our cafe is on the ground floor of a 20-something floor apartment/retail building. My coffee peer thought that maybe the pressure was coming from above which might cause too much pressure.
3. I spoke with the superintendent of the building and he laughed as he said that they pump 120 psi of water through the main system of the building (we could almost use line pressure to pull shots! Ha Ha!).
What do I do if too much pressure is coming into my espresso machine pump. It seems like it might not be geared to handle so much pressure. Also, I can only imagine that if a few people flush their toilets at the same time, the pressure would drop and recover pretty drastically.
Here is what I am looking at.http://www.espressoparts.com/product/90 ... _Tank.html
would something like this level out my incoming pressure? Thank you.