Importance of Increased Knowledge on Reliability of District Heating Pipes

District heating (DH) is a service that satisfies customers’ demands in the areas of heating, hot water preparation and the supply of heat to ventilation systems. Three generations of DH distribution technology are already in operation; the next generation of low temperature district heating (LTDH) will soon be upon us. However, without a reliable distribution system, it is quite difficult to utilize the concept of LTDH and remain competitive in the energy market. For that reason, this paper provides a comprehensive review of pipe reliability issues associated with DH systems. In this regard, discussions have been concentrated on factors leading to pipe degradation processes. Three groups of factors, namely physical, environmental and operational, were identified and examined. Allowable heat losses in the DH network and the creation of a pipe failure database were also discussed. The information collected in this paper leads to a better understanding of pipe degradation mechanisms and can be used as a tool for pipe failure prevention.