Hello Cavedwellers and Merry Christmas! Tony on limited posts over there again!!! LOL. You have more credibility, HVAC experience, and are less combative than 99.9% of posters over there. They could use your perspective. Thanks for going to Vermont! Here is an article that precludes the efficiency numbers coming from WDRP. Even I can understand the graphs presented. GLTA! Long and Strong http://web.njit.edu/~mitra/green_chemistry/EXP_1.htm pete