Nanofluids are a class of fluids comprised of a base fluid with nanoparticles in a colloidal suspension. These fluids have been shown to exhibit substantially higher thermal conductivity than their corresponding base fluids. In this book the authors perform a detailed analysis of the fluid dynamic and heat transfer properties of copper oxide and aluminum oxide nanoparticles in a 60:40 ethylene glycol and water solution. The analyses employ previously developed correlations for nanofluid thermophysical, fluid dynamic and heat transfer properties. Computational models developed by the authors that predict the performance of hydronic finned tube heaters and air heating coils with nanofluids and conventional fluids are presented. The authors report on several aspects of heat transfer performance including heating output, associated pumping power and others. The models predict that nanofluids may improve heating output, reduce liquid pumping power and the size of heating equipment required to achieve a given output.