This research reports a recent study application of the top heat mode closed-loop oscillating heat-pipe with check valves air pre-heater (THMCLOHP/CV/AP) for chili drying The THMCLOHP/CV had three sections of total size; the evaporator, adiabatic and the condenser section, of 180 mmΧ450 mmΧ190 mm (WΧLΧH). The THMCLOHP/CV was a copper capillary tube with internal diameter of 2.03 mm with equal length in three sections of 50 mm. The hot-air velocities were 0.5, 0.75 and 1 m/s with air inlet operating temperatures being 60, 70 and 80oC. The working fluids chosen to study were distilled water, ethanol and R123 with the filling ratio of 50% respect to total volume of the tube. Experimental data showed that the THMCLOHP/CV gave highest heat transfer rate about of 75.62 W where at filling R123, operating temperature 80oC and velocity of 1 m/s, and the highest effectiveness of about 0.1 where at filling R123, operating temperature 80oC and velocity of 0.5 m/s. It was found further that the heat transfer rate and effectiveness are increased with increasing the operating temperatures with the lower velocities. Consequently, the processing time could be chili drying by 2 hours and 20 minutes. The quality of color measurement of the chili exceeded marketplace.