Heating of buildings refers to the infrastructure systems of life support. Reliability assessment is an integral part of the operation of equipment for heating systems. The reliability of the equipment, its maintainability and the cost of ensuring reliability make it possible to identify the features of their mutual influence. Reliability analysis allows to identify causal relationships in the “maintainability-reliability-cost” paradigm and, on this basis, to select the best equipment option. The purpose of the study is to assess the technical state and the reliability of heating units in the points of heat supply of the centralized heat supply systems for buildings. The study was made on the basis of an analysis of the equipment operation data of thirty-six points of heat supply for the period from 2012 to 2017. Functionally significant and backbone units and blocks, as well as the weakest elements of the system, were identified on the basis of the “logic of failures” method. As a result of the study, a model was proposed for assessing the compliance of the design values of the reliability indicators for the heating units of the points of heat supply with the actual data based on the results of exploitation. © 2020