posts_nav_link doesn't work (leads to same home page)

I’m working on a site using the popular JournalCrunch theme. By default, its home page did not come with posts_nav_link so I’m trying to add it. I added this code to the bottom of the home.php page:

<?php posts_nav_link(‘ — ‘,’newer’,’older’); ?>

However, when on the home page, I correctly see the “older” link, which is hyperlinked to mysite.com/page/2, but when that page is loaded, the same set of posts (not the next group of older posts) gets loaded. While on page 2, the “newer” button appears, which correctly leads back to the home page (most recent posts).

Any clues on things to try? Working URL is here.