Used 1436 Sq Ft Shell and Tube Heat Exchanger. Mfg Industrial Alloy Fabricators, Inc. Shell MAWP 85PSI/FV@400F. (159) 1.50" 304 Tube MAWP 25PSI/FV@400F. Serial #D-1444. National Board #1280. Built 1991. R-Stamp#R-2955. Date 10/2008. R-Stamp# R-845. Date 6/2006.