My turtle floats on his back intentionally

by Michelle
(Maryland)

I have what I believe to be a baby box turtle (about the size of a ping pong ball), and he is the first turtle I have ever had.

I live in an old farmhouse with no electric heat, just a wood stove. My turtle lives in the kitchen near the stove, where the temperature can fluctuate. He also has a heat lamp for when I am working and not tending the fire.

Sometimes I catch him intentionally getting into the water and flipping upside down to float around on his back. He'll put his head under water to look for food or hold it out of the water to look at me.

Does he do this because he is getting uncomfortably hot or is it typical for them to float around like that just for fun? Do I flip him back over or let him remain upside down? What is the maximum temperature in which they are comfortable?

Thank you,
Michelle