This work investigates the viability and the energy efficiency potentials of a district heating network at very low temperature levels. A district with urban density in Munich, Germany, serves as example. For the investigation a thermo-hydraulic grid model is developed, which connects different building models to a district-wide co-simulation model. The simulation model of a traditional district heating network serves as a reference. Focus of the investigation is the influence of different demand scenarios, network typologies, heat densities and heat sources on network performance and district emissions, supplemented by an economic analysis of selected network typologies.