A full-scale test room is used to investigate experimentally and numerically the velocity and temperature fields in the case of a mechanical ventilation. Detailed fields are measured for three cases of ventilation air temperature: an isothermal case, a hot case, and a cold case. The experimental data are used to test two turbulence models: a first order k-ε realizable turbulence model and a second order quadratic RSM (Reynolds Stress Model) turbulence model. The RSM model predicts the temperature and velocity fields better than the k-ε turbulence model. In particular, global values of velocity and temperature coming from experiments are in good agreement with the RSM turbulence model. This conclusion is confirmed using a turbulence analysis based on Lumley triangles.