Hi,
1. I clicked empty all caches on the Performance -> Dashboard page but it did not clear up the page_enhanced page.
2. What I did was go to Performance->Page Cache and in the “Advanced” section I changed the garbage collection interval from 3600 seconds to 1000 seconds and click “Save settings & Purge Caches” then it automatically cleaned up the page_enhanced folder and freed up the 17GB space.
I will look closely on how this performs or if the page_enhanced page will continue to bloat up.