This book involves a thermal model and experimental testing methodology for sizing or selecting brazed plate heat exchangers (BPHEs). The BPHE is selected from a manufacturer's catalog and a testing rig is installed to verify the developed thermal model under various operating conditions. Mineral oil is tested in the rig at both hot and cold sides as a working fluid. The model is solved using equation-solving software. Results are compared with those of the tests and good agreement is obtained. The reported studies in this book are expected to guide thermal engineers in the selection or design stage of BPHEs.