Yes, FANLIGHT is a Scrabble word!

Letter values in Scrabble US: F 4, A 1, N 1, L 1, I 1, G 2, H 4, T 1.

Is it a valid word?

FANLIGHT is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a window above a door that is usually hinged to a horizontal crosspiece over the door
a window in a roof to admit daylight
a semicircular window over a door or window; usually has sash bars like the ribs of a fan

Also: transom window.