The Eastern Thermal Baths were equipped with two distinct praefurnia, basement and paved in beaten earth, obtained through the adaptation of pre-existing masonry structures. The first, is on the southern side, it is characterized by a narrow and elongated plant, where the fire was lit directly. The second, with a quadrangular plan, has two boilers and has been subjected to several renovations over time.

The Western Thermal Baths had praefurnia located in the southwest corner of the complex and it was possible to access through a small staircase open to a courtyard. Inside the first basement there was the oven that heated the octagonal shaped room. From here, a partly preserved tunnel with vaulted roof departed, in which were placed the four boilers that provided for the heating of the other rooms and the thermal baths.