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In the present study, a new analytical model for Earth to Air Heat Exchanger is presented. To this end, transient energy equation is solved employing duhamel's theorem and the soil temperature distribution is achieved with the concept of G function. Then, the outlet temperature will be achieved by solving the energy equation along the length of heat exchanger. In comparison to previous models, the present results are in better agreement with those obtained experimentally. Parametric investigation and feasibility study of this system in Tehran has been made using this analytical model for summer season with two different input temperatures. Parametric investigation showed for each mass flow rate, the corresponding optimum diameter is gained. It is observed that optimum diameter is a function of mass flow rate and operation time and independent of soil and input temperature of heat exchanger. For major mass flow rate supply, utilization of heat exchangers with minor mass flow rate is suggested; accordingly the temperature of heat exchanger is decreased. The depth and distance between heat exchangers can be calculated by the present model. It is also revealed this system can solely supply thermal comfort in continuous summer operation for cities with cold climate and low annual average temperature.