Does anyone know what is the size of the steam valve nut on LaPavoni pro. I will be installing a B-Push valve and need to make a wrench. Some sites say it is 15,16,17 size, not much help. Any help would be appreciated.

La Pavoni's special wrench is 16mm.
You can also get a 16 mm swivel socket as long as it's at the end of a wrench and not 90* like on a ratchet.

Like this:

LObin thanks a lot just what I needed

FWIW, I installed my B-push valve using a socket extension + universal joint. Removed the GH and went through the flange opening. No special tool needed.