It has a very good foundation for a horror game. Movement is solid and responsive and the environment is amazing. The environment has quite a few creepy elements to it, like the hanging vent cover near the computer station. It makes me wonder what could come out of it.
One minor thing you could implement is possibly a way to recharge the flashlight and/or an easier way of navigating when the lights go out, even if it's a small, exaggerated glow at the player's feet so they have to crouch down to the floor to take advantage of it. That way, the player isn't mindlessly stuck scrambling in the dark.
Otherwise a very solid start.