Used 1042 Sq Ft Doyle and Roth 304 Stainless Steel Horizontal Shell and Tube Heat Exchanger. (295) .75" x 216" Tubes Rated 550PSI @ 460F, FV @ 350 F. Shell Rated 425PSI /FV @ 550F. Approximately 44" OAH x 253" OAL. Weight 6,604 lbs. Serial #S2766-1. National Board #21580. Built 2015. Last use - economizer.