In the past years a great and growing demand has arisen for on-site dewatering test work in the mining industry. In order to comply with this demand, Metso has developed a new pilot scale pressure filter (VPA04). The aim of this thesis was the evaluation of the VPA04 against the Laboratory VPA filter (LabVPA), mostly regarding the repeatability of the test results. The performance of the VPA04 was carefully investigated and evaluated against a LabVPA filter in the Metso laboratory in Sala and also against a full-scale VPA filter operating in a processing plant in Zinkgruvan, Sweden. Process parameters, such as cake moisture, cake mass, filtrate weight, cycle time, air consumption and air drying were constantly measured and evaluated. The present thesis was carried out with dolomite, lead and zinc concentrate. During this experimental procedure different process conditions were tested in order to give values for predictions and repeatability. Each test was done with the VPA04 on site, with the LabVPA and cake samples were taken at the full-scale filters for cake moisture analysis and comparison. The object of this evaluation was to analyze the repeatability of the same machine with different settings and materials or to determine a usable factor in order to establish a comparison between the VPA04 and the LabVPA filter. In cooperation with Metso, theories and ideas regarding the reasons for the variance between the machines have been developed, as well as suggestions for an improved testing procedure and an appropriate presentation of results on the basis of the results of the conducted tests have been established.