Used 1000 Sq.ft. horizontal Shell and Tube heat exchanger. 304-SS Shell rated 75 PSIG @ 850 deg., 304-SS Tubes rated 75 PSIG @ 650 deg. Shell - 1 pass; Tubes - 2 pass. Shell dia: 22". (324) 3/4 x 16' L tubes. Mfg by Heat Transfer Equipment Co, NB # 250. Type: AES. NOTE: There is a dent in the shell.