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

In the last years the importance of part load conditions in the estimation of chiller performance in real world operation has been completely acknowledged. As a matter of fact, chillers are sized for peak loads, so they usually run under part load conditions, far from the full load ones, taken as references in catalogues. Some methods for these calculations already exist, both in Standards and in building energy simulation programs, but they lack an extensive validation in actual HVAC systems. In this regard, the present paper compares the chiller performance estimated via the calculation method contained in Standard EN 14825 against monitored data taken along an entire cooling season, both in a small HVAC plant and in a large one. In the present paper a variation of the calculation method contained in Standard EN 14825 is used