The connection refused you get means that your app was not able to establish a socket connection to its target. Typically this means that you've given the wrong hostname or port, or that the service on the other end isn't running.
I suggest that you look into the logs, error messages and/or configuration to find out what address is being used and why a connection can't be established to that address.
Using Telnet to try and establish connections yourself may be very helpful in preliminary investigation.
In addition to what othos suggested as possible causes, this could also be the result of a firewall interfering with the network connection on those ports between your Pega server and the soap UI client.