I have setup OS:SpaceInfiltration:DesignFlowRate in a model as follows:
Schedule = Fractional (Value=1 for all times) Design Flow Rate Calculation Method = Flow/ExteriorWallArea Flow per Exterior Surface Area = 0.0025 Constant Term Coefficient = 1 Other 3 Coefficients = 0
My understanding (after reading the Input/Output Reference) is that this should result in a constant flow of infiltration air (for all times) at the volume flow rate specified. However, when I review results, the infiltration rates in the model appear to vary significantly. Any ideas about what is going on?