The paper presents a procedure for calculating the annual energy consumption of a large construction object whose heating system comprises heat pumps connected in a water loop and offers a zone map of the Russian Federation depending on the potential efficiency of using water-loop heat pump systems. We have considered the traditional system with heating units and cooling fan coil units and the proposed new system with water-loop heat pumps. The procedure for calculating the energy consumption of these systems is described. Based on this procedure, we have calculated the coefficient of relative energy efficiency of using water-loop heat pump systems for Russian Federation and constructed a zone map of Russian Federation depending on the potential efficiency of using these systems. We have analyzed the energy efficiency of water-loop heat pump systems for large construction objects. The proposed procedure and the zone map are applicable for calculations of annual energy consumption of heating systems with heat pumps included in the water loop and can be recommended as a tool for choosing the circuit design.