On-field validation of a seasonal performance calculation method for chillers in buildings

In the present paper a variation of the calculation method contained in Standard EN 14825 is used indeed. In particular, in this variation of the EN 14825 calculation method, the interpolation between the values of EER rated under part load conditions is performed by means of intermediate parameter Z, equal to the ratio of the electrical power consumption under part load conditions to the electrical power consumption under full load conditions. This interpolation method allows the HVAC designer to draw more reliable profiles of PLF (Part Load Factor) versus the capacity ratio (CR), in order to increase the accuracy in performance prediction under part load conditions. As a matter of fact, this interpolation method allows the HVAC designer to achieve a better estimation of the EER at low values of the part load ratio, especially when compared with the linear interpolation method suggested in Standard EN 14825.