s1v2 increasing brewhead pressure

[scot]

Looking at the pressure gauge, after I pull a shot the pressure drops back to the house pressure, then slowly increases as the unit sits vs staying on house pressure which it used to do. This happens even if the temperature is not going below the set point. As soon as I hit the button, the pressure in the brewhead drops properly, then the pump builds it up right. After a few minutes, it is back to slowly rising.

I have a regulator in-line.

Any ideas?

[chas]

Due to street water pressure or the pump pressure coming in, the water output of T#3 flows into T#1 through a built-in 1-way valve which is supposed to prevent flow backwards from T#1 to T#3. However, if this valve leaks you will get exactly what you are seeing. This valve consists of a small ball bearing with a spring behind it inside the output port of T#3. Water flowing from the street pressure or pump pressure pushes against the ball bearing, compresses the spring, and opens the valve. If the pressure on the "right side" of the valve exceeds the pressure on the "left side" it should push that valve closed.

Your main options are to either live with it or replace T#3. However, it may be possible to remove T#3, disassemble it, clean out mineral deposits or whatever is blocking it, then reassemble and replace. I've never had to do either of these options before so I can't advise on the difficulty of removing the valve or the cost of a new one if you can't repair the current one.

BTW: I suspect that your water pressure regulator is also adding to the issue since it is blocking full flow from street pressure. In other words you probably wouldn't see the pressure fluctuations if it weren't there but the issue with that valve would still be happening. If you have the pressure regulator set below 3 bar (45 psi) you might want to raise it to that level and see what happens.

The bottom line is that this has absolutely no impact on the operation of your machine. What it does mean is that there is some water flowing from your machine back into the water lines. In general this is considered a bad thing relative to local plumbing codes.

S1V2Flow.jpg (31.82 KiB) Viewed 5256 times

[scot]

I see where t#3 is. Yeah, that would be a total pita to remove, basically a total system disassembly, though maybe with the right tools it could be done, since it is right there. Darn Italians, they design wonderful things that just don't like to be taken apart easily.

I've turned the pressure up to 45psi from 30 and will monitor. It went up to 4bar/60psi while heating but it seems to be steady there for now. I'll check again in a few hours.