La Spaziale Mini Vivaldi II - overflowing vacuum breaker

#1: Post by **CamBam_HB** » October 16th, 2021, 7:13 pm

Any idea what would cause the vacuum breaker valve to overflow?

I had an issue with the vacuum breaker not closing properly and recently replaced it. While taking it out, the middle pin dropped into the steam boiler and i had to disconnect everything and take out the boiler to get it out.

So far I've replaced the following in trying to fix the issue

Vaccum breaker valve
Water fill probe (replaced with newer model)
Clean all the inlets pipes, hoses etc - retightened with teflon tape.
Water solenoid valve (1st thing replaced, which then led to the vacuum breaker issue).

When turning the unit on, the steam boiler seems to heat up properly but the vacuum breaker eventually fills up and overflows.
I've had the steam boiler turned off and tried to just pull a shot, i see the pressure go up to about 7 bars and the vacuum breaker also fill up and overflow.

#2: Post by HB » October 16th, 2021, 7:22 pm

Sounds like the water level sensor isn't working -- it's not detecting ground until the steam boiler is filled to the tippy-top. Once the water heats up, it overflows out the vacuum breaker. You can verify the steam boiler is overfilled by measuring with a wooden dowel through a fitting on top of the boiler.

For those following along, a water level sensor helps maintain the steam "head space":

From Can someone please explain false pressure?

My assumption is that instead of having a good amount of headspace (1.89" and 2.13" in the diagram above for another espresso machine, not yours), the steam boiler is filling to the top. Another possibility is the inlet solenoid for the steam boiler isn't closing completely, leading the steam boiler to eventually overfill.