This forum is now read-only

To login to the new support channel and community forums, go to the Support Portal

Expansion valve adjustment and pressure

The new heating element is working well. I decided to get around to adjusting the expansion valve due to the intermittent running of the pump, since installing the digital module a couple of months ago. I had been putting this off because it only happened if I set the preinfusion pressure at 4 bar or higher. I noted a few issues that I wanted to run by you.

First, I noticed that my app now does not display pressures higher than 9.9 bar. When pressure increases above that it "wraps around" back to 0. I did not notice this happening before a recent update in the app.

Second, i've noticed that no matter how I adjust the expansion valve (following your instructions in the permanent file), the maximum pressure displayed is 12.3 bar (displays as 2.3 bar). What will change is how long that pressure is held before it drops lower, leading me to suspect that the actual pressure might be higher.

Anyway, a few days ago I set the preinfusion pressure to 6 bar and adjusted the extraction valve by about 1 turn at a time. However, even at the maximum tightness, which took a while to reach, the peak pressure is 12.3 bar. I assumed that was incorrect and turned the screw several times counterclockwise, ending up at a setting where the pressure would cycle between about 7 and 12.3 bar. At this setting, after about an hour, the lower end of the pressure cycle drifted down to 6 and the pump activated. I changed the preinfusion pressure to 4 bar and called it a night.

The next day I noticed that after about 4-5 idle hours, the pressure would drift down to 4 bar, low enough to activate the pump. It was cycling between 4 bar and around 10 bar. I got out my wrench and hammer and made sure all the connections were tight, but this made no difference.

This morning, I woke to the sound of the pump, about an hour after my timer had turned on the machine. I checked the machine and the red light was on continuously, but the boiler pressure was zero. The machine was warm. I turned it off for an hour and checked the heating element connections and temperature fuse, which were OK. I inspected for leaks and found no moisture anywhere. I restarted the machine and the boiler cycle is back to normal. [strike] However, the app is showing constant pressure at "2.3 bar" and is not cycling lower. I'm concerned that the actual pressure is higher than 12.3 bar but I don't know how to interpret it.[/strike] (Disregard this, explanation below)

My plan at this point is to make a few counter-clockwise turns on the expansion valve to get the pressure down. As I'm confused by all of these recent events, I thought I'd ask for some input also.


  • An update:

    [strike]Previously (even an hour ago when I last tried it), pulling down the lever would lead to the app showing a corresponding drop in pressure, and then a jump back up to "2.3 bar" afterwards. Now it's stuck at 2.3 bar all the time. I tried restarting my phone and the app but it's still stuck on 2.3 bar.

    I adjusted the expansion valve and after a few counterclockwise turns the pump was briefly triggered. But even at that point, the app was stuck at 2.3 bar. So it seems that the machine is seeing a change in pressure but the app is not.[/strike]

    Nevermind, it seems the machine has been "offline" for the past 30 minutes, which would explain the frozen 2.3 bar reading.

  • image

    As far as why it went offline, it looks like the wireless dongle fell out of place. Reiss, I had sent you pictures earlier of how Customs had opened it up and messed with it. I think that predisposed it to falling apart. I was able to reinstall it but I'm going to need a replacement soon.
  • Back to cycling between 7 and 12.3 bar. I'll report back if there are new problems or if the boiler stops heating up again. The dongle is back in place but is wobbly.
  • Since I fiddled with the expansion valve the machine has been well-behaved today, so I think most of my concerns are resolved at the moment. I'll leave it up there in case the boiler issue comes back. I do need a new dongle though.
  • im on the case leo. i would say if your pump is chipping in once an hour to restore pressure thats pretty good to be honest. reiss.
Sign In or Register to comment.