This paper presents a virtual flow meter(VFM) to estimate the chilled and condenser water mass flow rates for chillers using measurements commonly found in a building automation system (BAS). Five scenarios of available measured data are used to explore the methods as the number of sensors available to compute the mass flow rates are reduced from ten to six. Two VFM models and preliminary results are presented using both VFM models with data from an ice arena located in Montreal, Canada, for a chiller with a reciprocating compressor. This case study shows a good agreement between the predicted and measured results for the chilled water mass flow rate. This case study also shows good estimates between the VFM model B with six sensors, combined with manufacturer data, with that ofVFM model A using nine sensors, showing that for this case study the accuracy of the models were not affected by the reduction in available sensors.