The present work conducts an experimental investigation into the influence of flow, thermodynamic and geometrical characteristics of the wavy strip on exergy loss and dimensionless exergy loss in a tube in tube heat exchanger. The working fluid is water with hot water passing the inner tube and cold water passing annulus. Wavy strips with four different angles and three widths were investigated experimentally. The result of exergy loss and dimensionless exergy loss for various conditions is presented and on the basis of curve fitting, three empirical correlations are suggested to predict dimensionless exergy loss in a double tube heat exchanger.