An irreversible heat pump was investigated via entransy analysis and performance criteria. In the analyses, two different convective heat transfer laws were applied to the considered system: the Newton and Dulong-Petit heat transfer laws. The irreversibilities in the system are the result of a finite heat transfer rate, a heat leak and internal irreversibilities, including friction, turbulence etc. In this study, a thermodynamic analysis was performed in detail, and the numerical solutions were used for the conducted analysis. The maximum entransy dissipation (critical points) ranges from 18436.7 kW K to 18855.3 kW K according to y for Newton's law; however, there is no maximum point for the Dulon-Petit law. It can be concluded from this study that entransy should be used among the basic thermodynamic criteria. (C) 2014 Elsevier Ltd. All rights reserved.