Pool boiling heat transfer coefficients were measured for solutions of salts with positive solubility in water. The effect of the dissolved salts on nucleation site density, bubble departure diameter and bubble frequency was also investigated. The results show that at low heat fluxes heat transfer coefficients can be considerably lower than corresponding values for distilled water. At high heat fluxes the negative effect of the dissolved electrolyte gradually decreased and finally some improvement in heat transfer coefficient was observed. A correlation was developed for nucleate boiling of aqueous solutions from salts with positive solubility. Assuming that the mass transfer resistance is limited to the liquid side, the proposed model allows the prediction of heat transfer coefficients from boiling point data of the respective solutions. Comparison with a significant number of experimental data for different systems indicates that the model should be sufficiently accurate for most practical applications. (C) 2003 Elsevier Ltd. All rights reserved.