Description: We show that the effect of size dependence of the melting temperature of nanocrystals may be used to govern anomalies of thermodynamic properties of nanocrystals in the premelting range. For example, if temperature of nanocrystals is near the melting point, their mechanical contact should result in a change of the temperature and release of some heat. We discuss fundamental possibility of construction of a "heat pump" to extract thermal energy from a low-temperature medium.