Lelit Bianca sputtering from the anti-vac outlet every few seconds

[mighty patrol]

My Lelit Bianca (v1) is sputtering from the anti-vac outlet every few seconds. Just a little sputter and then another one a few seconds later.
I've attached a picture and a 30 seconds video where you can see the frequency, maybe 5 sputters in the 30 secs.

I just replaced the anti-vac and even right after the replacement this continued. Is my anti-vac a bad part or is there a way to install it improperly? Or might it be something else entirely?

(The machine has been running for 8 hours now, this isn't the initial sputter right when the anti-vac first closes)

[tender swift]

Afaik there’s three valves that outlet on that point. Remove the tubes from the anti vac and the steam overpressure valve (machine off!!)

Then let it heat up and look from afar to see which valve it is. I suspect it’s the overpressure valve if you’ve replaced the other one.

So look from a little distance, if it blows it’s pretty scary

[mighty patrol]

Ohh, thank you. That makes sense actually.

Just to be sure you're saying both of the ones I marked cyan here go into that outlet?

[tender swift]

Yes and also the brew boiler OPV

But that generally only puts out water when heating up

You could also keep the tube on and see if you can see it vent, it’s a clear tube

Should be pretty obvious

[mighty patrol]

Great idea, that totally worked. I recorded a video showing all the three tubes and it was very clearly the anti-vac one. So this is a video of me scrubbing through the real video just to speed things up a bit. Would you agree that that's not normal?

[tender swift]

Cant see the other one

[mighty patrol]

These two are two frames apart in the video, see how the droplets cleared?

[tender swift]

But yeah if that thing sputtering and it venting out in the front match, should be clear

[mighty patrol]

This is the full, original video

[tender swift]

In that case I’d remove the tube and test once again to be sure

Shouldn’t be too aggressive if not the safety valve

Mostly since you replaced it already this is super odd

[mighty patrol]

Alright. So just to be sure, after the initial blow when the anti-vac is closing, there should be no more nothing coming out, right?

So it should be totally closed until I switch off the machine, correct?

To be honest, I could even hear the anti-vac make some noises

[tender swift]

Yeah it should be completely closed after the first hiss when reaching boiling temp, however it’s very common for anti vacs to leak a tiny bit, which sounds like a faint whistle