I’m a total rookie need help with basic repairs

[espressomaker]

Hi all,
I bought a mini Vivaldi 2 for 1500 supposedly in like new condition… the pressure gauge wasn’t working a no show and the vacuum breaker is overfilling. I descaled the machine and the vacuum breaker stopped the overfill yet after pulling some shots it started the overfill again.
Should I just descale again?
In regards to the pressure gauge could I use this one from espresso parts https://www.espressoparts.com/products/ ... 6183072955
And what fittings and tubing would I need for a new connection from the gauge to the steam boiler?
Thanks for any and all help

[Doodee]

I had a similar issue in my Mini vivaldi.
Try cleaning the fill probe in the steam boiler and also check the cable and make sure there is electrical contact. I needed to remove a little bit of the shielding from the wire to ensure there was a contact.

[espressomaker]

Thank you so much for the response!
After paying closer attention to the goings on of my Vivaldi I have these additional points to add
1 It never overfills by itself only during brewing
2 even when pulling water through the group only if there is a pressure build up either because of coffee or a blind portafilter does the water enter the steam boiler

My conclusions are that it must not be due too a faulty autofill system but due to back flow caused by the additional pressure while brewing
My amateur internet sleuthing led me to a part called the inlet solenoid valve does it make sense that clogging in this valve could cause this or am I totally off?
Thank you again for any and all help