What is this?
I adjust the OPV of my Andrea with a blindfilter at 10 bars.
Pull some shots and it settles nicely at 9 bars.Perfect for me.
But each shot I pull it climbs till it's back at 11 bar.
What happens?
Could it be the silicone tubing pulls the valve back to its former position?

Climbs over how many shots?
If over several days / weeks, OPV may need a rebuild

Is the gauge at 0 when the machine is cold?
No, bad gauge

espressotime wrote:Could it be the silicone tubing pulls the valve back to its former position?

Absolutely not - try turning the 12 mm adjusting nut with your fingers and you will see what I mean.



Adjust the 12 mm hex such that you read 9.0 bar with a blind filter. This will give you 8.5 to 8.75 bar at the coffee during brewing which should be just right.

Order some spare parts:

The rubber valve insert in the OPV body can be replaced; sometimes shops have the OPV body as a spare part with the insert in place. Replace the o-ring on the adjusting assembly and lightly lubricate it and the threads to the left with Dow 111 or equivalent food-grade grease.

Sometimes simply disassembling, cleaning and reassembly will get it behave. My Isomac had an OPV that was easy to turn. I had to disconnect the silicone tube when I adjusted it or it would twist over time. The vibration from the pump and torque from the twisted tube would slowly turn it back.

+1 on what Dave said.. The first time I adjusted the OPV on my Anita, it eventually worked its way back up to 10.5 or so.. probably over the time of a month or so, thereabouts.

Once I adjusted it again, it didn't move until later down the road when I added a new seat to it. First time adjusting it, it drifted back up. Again, I adjusted it where I wanted it, and then it stayed.


Id say adjust it back to where you want it, and keep an eye on it over the next few weeks. If you still have the problem, Id take it apart, add a new valve seat, and reassemble.