A procedure for rating the seasonal coefficient of performance of heat pump dishwashers using a minimum dataset.

The present work is aimed at mapping the thermodynamic performance of a dishwasher operating in the socalled ‘Ecomode’, where the heating is provided exclusively by a heat pump, in accordance with the requirements of the IEC 60436 standard. Tests were carried out in a climate chamber that allows strict control of the surrounding air temperature. In addition, an auxiliary rig was built to control the dishwasher water supply temperature. Initially, a test matrix was proposed for screening the appliance performance in a broad envelope of operating conditions for a given washing load. Later, the test matrix was reduced to get the most out of the standardized tests with a minimum set of data. To this end, a simplified mathematical approach was put forward to reduce the experimental data to come out with key system parameters, such as the thermal conductance and capacitance of the washing cabinet, and the seasonal heat pump coefficient of performance (SCOP), which cannot be easily obtained by means of direct measurements.