<p>One of the passive solar systems that plays a major role in building natural ventilation and cooling is the solar chimney (SC). This system, which uses solar energy to increase mass pressure, in addition to significantly reducing greenhouse gas emissions, improves the efficiency of heating and cooling residential space. Various techniques have been presented to optimize the performance of an SC. An SC combined with an earth-to-air heat exchanger (EAHE) can provide fresh air and cooling capacity simultaneously with no electricity consumption. In the present work, a room equipped with SC and EAHE is considered using the water bath model. The flow rate is measured, and the flow pattern is recorded using the particle image velocimetry (PIV) method. The performance of the combined system, named SCEAHE, and the influences of different factors on the fluid flow rate are assessed. According to the results, when the solar radiation is maximal (700 Wm⁻²) and the underground channel passes through a depth of more than 3 m, the velocity of the fluid flow entering the room and its temperature difference with the ambient air become maximal. This system can provide 20% of the ventilation load of the building, which can put the interior space in the range of thermal comfort in terms of temperature. On the other hand, the cooling capacity of this system is 60 BTU for a valve with a diameter of 35 cm.</p>