: 23-28
Received: February 21, 2021
Revised: June 15, 2021
Accepted: May 13, 2021
Technical University of Kosice, Slovakia, Institute of Architectural Engineering
Lviv Polytechnic National University
Department of Heat and Gas Supply, and Ventilation, Lviv Polytechnic National University

One of the main tasks around the world is to reduce energy consumption with constant consumer comfort. The hot water supply system uses a significant part of thermal energy and requires no less attention than the heating or ventilation system. The amount of heat loss from hot water distribution systems is of great importance for the energy consumption of buildings. In winter, part of this heat is used for space heating, in summer they are unused and is considered as lost heat. 

For this reason, this paper considers the influence of water velocity in the pipe, pipe size, and water temperature on the total heat losses in the insulated hot-water distribution system. 

The data are presented in tabular and graphical form. A graph of the dependence of the amount of heat loss on the temperature and velocity of hot water is obtained.

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