A hot and uncomfortable kitchen contributes to productivity loss, employee turnover, and eventually profit loss for the restaurant operator. Using thermal displacement ventilation in kitchen environment allows for a reduction in space temperature without increasing the air-conditioning system capacity. Application of two systems is compared in a typical kitchen environment using CFD modeling. Often kitchen exhaust hoods are provided with untempered makeup air. It is not uncommon to hear the claim that this makeup air is exhausted through the hood without having any effect on kitchen space temperature. The validity of this claim is analyzed in this paper for two makeup air configurations using a combination of measured data and results from CFD models. Kitchen space temperature increase is calculated as a result of supplying unconditioned makeup air during the summer.