Used 200 sq.ft. vertical shell & tube heat exchanger, Mfg. by Doyle & Roth Mfg Co. Inc. 316L stainless steel shell rated for 100 psi @ 350 Deg. F, -20 Deg. F @ 100 psi, 316L stainless steel tubes rated for 100 psi @ 350 Deg. F, -20 Deg. F. @ 100 psi. Year Built: 1990. Weight - 1299 #.