The price per unit of water heating can vary depending on the amount of hot water consumed in each house and the heat consumed.  The total water consumption meter of a residential building counts only the consumption of cold water.  The hot water readings provided by the apartment owners are used to determine how much of the total cubic meters of cold water consumed was consumed as hot water.   Thus, the heat energy entering the house is used for the following services:    

• for heating, which does not work in summer; 
• for heating hot water;    

• circulation of hot water (if a circulation line is built in the house). 

Further, the calculations are carried out by the house manager, choosing one of the methods approved by the community of apartment owners.   Different calculation algorithms can be used in each house, as well as the calculation algorithm can change in the winter and summer seasons.