Tuna Noodle Casserole

Besides trying new recipes, I am hoping to master some staples, like this recipe for Tuna Noodle Casserole. It was quick and easy, other than waiting for the water to boil for the pasta - I always hate that part. It did come out a little runny, though, so I might use less milk next time. Also, this was my first time using the broiler. Can anybody tell me if you have to preheat the broiler? The first step in the recipe says to preheat the broiler, so I was waiting for the preheat indicator to turn on and it never did.