District heating is one of the most efficient and environmentally friendly ways to satisfy heat demand in densely populated areas. It allows reducing the global fuel consumption for heating purposes thanks to a centralized production. In these systems, thermal energy is sent to users through an underground network that provides hot water to the users. This paper it’s been developed in collaboration with IREN s.p.a. and it deals with Turin district heating network, that is, with its 5700 m3 of heated volume, Italy’s biggest network. Thermo-fluid-dynamic simulations of such large networks usually require large computational resources because of the complex topology that also involved loops.