Post Navigation as h1

Hello,

I have in my twentyfourteen the post navigation as a default h1 i every article. I am using a static homepage, so this problem appears only in the article pages.
Since I would like to have only the blog title as h1 (At the moment I have the h1 twice in every article) I would like to remove the h1 from the post navigation.

Where can it find it in the editor and which files I need to modify?