Script from external file still firing even if the element is empty

Script from external file still firing even if the element is empty

I have 2 html files

 1. main.html
 2. external.html - contains script tag

external content will be loaded to main.html once a user click the button using jquery.load function

Now my problem is if the user click twice the load button, the functions inside the external.html fires twice also even if i emptied the div element in main.html

i tried

empty()
and
html("")
functions to clear out the content of the div but still no luck.

this is my code http://plnkr.co/edit/XLZGquoebTTHahgJWNOk?p=preview