A lot depends on the browser being used, and some of it can depend on the server. Some browsers will check what the server is offering and no reload something they think they have that is already the same.
However, to update content, you normally have to update the page.
I typically don’t use a refresh time out causing the page to refresh itself but rather set a tag so that when the user does a refresh they get a new page.
<META HTTP-EQUIV="expires" CONTENT="0">
Tells the browser not to use the cache for items, but reget them.