A preliminary screening procedure is described for an MINLP formulation of the Heat Exchanger Network Synthesis problem. The objective is to overcome computational difficulties associated with a large number of binary variables and nonconvexities. The procedure relies on the use of an aggregated model. Through preliminary screening, poor suboptimal solutions are eliminated, and a reduced MINLP problem is solved that contains only those combinations of alternatives with potential costs no greater than a base-case design.