Per IRS Publication 17, page 7:
Even if you don't have to file, you should file a federal income tax return to get money back if any of the following conditions apply.
5. You qualify for the health coverage tax credit. See Form 8885, Health Coverage Tax Credit, and its instructions, for more information.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the webpage or document at the time it is accessed.