Hot fluid passes through the inner tube and cold fluid flows through the outer tube in an experimental study of a Concentric Tube Spiral Coil Heat Exchanger conducted in a Counter Current method. The temperature data was recorded while the flow rates in the inner tube and Annulus were altered five times each. To get total heat transfer coefficients as well as heat transfer coefficients for the inner tube and annulus, the Wilson Plot method is utilised. The Nusselt Number gained from the experiment was compared to the Nusselt Number obtained through the development of a mathematical model using Regression Analysis. The inner Nusselt Number was linked to Dean Number, while the Annulus Nusselt Number was linked to Modified Dean Number and a new Dimensionless Number called "M Number." The experimental data was well-fitting with the Theoretical one. The hydrodynamics (pressure drop) and heat transfer properties of the concentric tube spiral coil heat exchanger were also examined.