A series of eighteen (18) simultaneous calorimeter room and flue loss tests were performed on three wood burning stoves to provide a set of data for establishing the relative accuracy of various flue loss calculation procedures and data handling techniques. Parameters investigated include flue moisture, fuel chemistry , hydrocarbon analyses , data averaging , and thermal storage. Statistical analyses show limited improvement potential in the relationship between flue loss and calorimeter room results with the use of specific calculation procedures and data handling techniques . However, statistical analyses did not indicate any clear approach for significantly improving results obtained from the current flue loss method. Improvements may be possible by the direct measurement of combustible losses.