A new type of solar water heater called Spiral Flow Flat Plate Solar Water Heater (SFSWH) was created and tested in Kovilpatti, India. The SFSWH was compared to a traditional parallel flow solar water heater using a computer simulation program called TRNSYS. The results showed that the SFSWH performed better in terms of heat transfer, outlet temperature, and efficiency. The accuracy of the TRNSYS model was confirmed through an experimental setup in Kovilpatti. Overall, the SFSWH model proved to be more effective than the conventional parallel flow water heater, making it a reliable alternative for solar water heating.