Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
The Curve Fit Tool is used regularly to generate performance curve coefficients for many empirical models (e.g., coils, chillers, etc.). The data needs to include multiple data points for each independent variable. You said " The data I have includes A set of condenser inlet air temperatures - ECT (°C) and for each temperature ..." so I assume you have a set of data at only 1 leaving evaporator temperature. If this is correct, then the answer is maybe. If you have more than 5 data points (number of independent variables + 1) then you should be able to calculate the performance curve coefficients. However, the problem with this type of data set is that the coefficient for leaving evaporator water temperature will be 0. That's OK if in your simulation you ensure that the leaving evaporator water temperature always matches the temperature of your data set. If, in your simulation, the leaving evaporator water temperature deviates from the value in your data set, then your model will not include the variation in performance at that off-design temperature.
