How do refund checks work? If I have a loan of $5000 and my balance is somewhere in the 4000s do I still get a refund? 
You get a refund if your grants and loans exceed your billed costs. And it goes by semester, yes.
But you need to contact your college to find out their procedure. My kid needed to request a refund. She also had the choice of leaving it in her account for future terms.