Why is the hotel bathroom so warm?

The heating method used in the hotel is geothermal.

There is heating in winter, many bathrooms have radiators, some are exposed outside, and some are decorated with packages. The bathroom in an air-conditioned room is naturally not too cold, because the air is circulating. As for the problem that the bath is not cold, it is because after the hot water is put for a while, the temperature in the water will be emitted, and the hot water will not be cold when it is poured on the body.