The effects of recycle at the ends on the heat transfer through two parallel plates with one side heated and the other side insulated in cool-thermal discharge systems by melting ice have been studied to produce chilled air under constant heat flux at the free liquid surface. The mathematical formulation was derived from an analysis of the heat transfer coupled with a moving boundary to estimate the required air mass flow rate by direct contact of air with melting ice. The numerical results show that the recycle can enhance the heat transfer rate, and thus lower outlet chilled air temperature during on-peak daytime hours, represented graphically and compared with that in an open duct of the same working dimensions without recycle. Three examples of inlet air temperatures with specified discharge fluxes are discussed. The effect of recycle on the enhancement of heat transfer efficiency is also delineated.