This paper presents the results of an analysis and measurements performed on an earth-air tunnel system for cooling and heating buildings. The experiments were performed all year around on a large, already built tunnel, the cooling~heating performance of which was also studied. The measurements were verified by a simple theory. The cooling capacity of the tunnel was found to be considerably greater than its heating capacity. R(~sum~---Dans cet article, on prlsente les rlsultats d'analyses et de mesures conduites sur un systbne de tunnel terre-air qui peut refroidir et chauffer un batiment. Les explriences ont dtΒ’ conduites tout au long de l'ann& sur un grand tunnel dljfi existant. Les mesures furent vlrifi&s fi l'aide d'une thlorie simple et la performance du systkme de chauffage et de refroidissement ffit aussi itudile. On a trouvi que la capacitl de refroidissement du tunnel est beaucoup plus importante que sa capaciti de r[chauffement. b ca D Dm h~ hD K L m mw 0., Rt T r, w w, y / p AT Nomenclature : breadth (m); : specific heat of air (kJ/kg Β°C); vapour diffusivity (m2/s); : mass diffusivity (m2/s); : convective heat transfer coefficient at the inner surface of the tunnel (W/m2Β°C); mass transfer coefficient (kg/s.m2); thermal conductivity (W/reΒ°C); length of the tunnel system (m); mass flow rate of air (kg/m2-h); rate of evaporation of the water mass (kg/m2-h); heat flux due to convection (W/m2); heat flux due to evaporation (W/m2); : total heat flux due to convection and evaporation (W/m2); daily cooling/heating capacity of the system (kWh); resistance of the sensor at Β°C (1"1); resistance of the sensor at tΒ°C (l'l); tunnel air temperature (Β°C); surface temperature of tunnel (Β°C); humidity ratio; saturated humidity ratio; position co-ordinate (m). latent heat of vapourization (J/kg); density of air (kg/m3); change in tunnel .air temperature (Β°c).