1) do not try to use onchange. onviewactivated should be used
2) add rich:messages to your page
Ok, that sets the value correctly, however the action is called even if there is no change made to the text. In my case I don't want to fire the save method if the user has not made a change, hence why I was trying to use onchange.
Is there a way to only fire the action only if the value has changed?