We do this sometimes. I would say that if your going to leave it for more than a day to let the ranger or host know - as others have mentioned.
Quick note - we left our trailer for just a day (early morning until about 9pm) and when we came back, the fire ring was moved to the site next to us. The people had two. They left the next morning when I saw that it was moved. I am glad I didn't leave anything outside for them to move home with them. Moral to that story is lock everything up, especially if you are planning to leave for multiple days.