netstat -lptu
gives me
tcp6       0      0 [::]:16514              [::]:*                  LISTEN      1314/libvirtd   

so the server is correctly listening on interfaces.

My /etc/libvirt/libvirtd settings are defaulted.
My /etc/default/libvirt-bin has "-d -l" options so server is listening. 

If I do virsh -c qemu://143.225.229.190/system (that is my ip or an ip belonging to my network) I get "connection refused".

How come?
And note that if I put my address, 143.225.229.190, as listening address in the libvirtd conf file, I get "this address class is not supported".