To use the l4d server follow these steps bellow.

1:) | Start l4d and get to the main menu.
2:) | Open console at main menu ( ' ` ' key) and type the following....

mm_dedicated_force_servers 208.167.242.22:27015

...after this is typed in send the command. There should be NO error or response by the console if you did this correctly.

3:) | Make a lobby and enjoy :)