Im gonna show you an alternative way to join IRC chat without downloading mirc, this is a faster way imo.
1- Open your browser.
2- Go to chat.mibbit.com
3- Next to "Connect:", open the drop-down menu and select GameSurge [webirc]
4- Next to "Nick:", type in the nick you want. (Using the nick same with the forums will be a good option imho.)
5- Next to "Server:", type in #phrozen-keep
6- Click on "Connect"
You are in!
For further information, you can visit the official website: http://mibbit.com/