Long-term savings can be achieved by small household improvements to deal with the increasing energy costs that are important to all of us. Hot shower greywater is discharged to the environment with a significant amount of thermal energy. In this study, unlike the studies in the field, the recoverability potential of the shower greywater thermal energy was experimentally studied and compared by the horizontal and vertical connection of the helical coil and brazed plate heat exchangers to a unit shower cabin. The shower water heating energy consumption of thermosiphon can be reduced by approximately 16.13% and 24.69% by mounting the helical coil heat exchanger horizontally and vertically. The saving rates reach 20.62% and 27.34% for brazed plate heat exchanger, too. It could be assessed that annual energy saving can be a minimum of 247.1 kWh and a maximum of 418.7 kWh for an average family of four people. The economic size of the saving was determined between $25.2 to $42.7, annually. The installation cost of a heat exchanger for a shower cabin is $87 and it was determined that the payback period could be 2 years. The reduction of carbon dioxide emission by the possible saving of energy is an estimated minimum of 203.85 kg/year. The study aims to contribute to the creation of literature for academic studies and design processes, as well as awareness for practitioners and investors.