<p>This study investigates the effects of inlet pressure and valve position on the performance of a self-fabricated Ranque-Hilsch vortex tube (RHVT). Experiments were conducted at inlet pressures of 40 psi, 50 psi, 60 psi, 75 psi, and 85 psi, with measurements taken for various conical valve positions at the hot tube (0, 2, 4, 6, 8, and 10&#xa0;mm). The optimum operating conditions for these parameters were analyzed using the statistical tool ANOVA, and the influence of each parameter on the cooling effect and coefficient of performance (COP) was quantified. Results show that as inlet pressure increases, the cooling effect improves, but the COP initially decreases due to higher compressor work. Beyond a certain pressure, the COP begins to rise again. It was observed that increasing the hot side opening or moving the conical valve away from the tube initially reduces the cold air temperature to a minimum before it starts increasing. A higher COP was achieved when the hot tube outlet valve was closer to the vortex tube, with the maximum COP occurring when the hot outlet side was fully closed. ANOVA results indicate that valve location has the most significant impact on COP, accounting for 91.38% of the variation, compared to 3.87% for inlet pressure. Similarly, for temperature separation (ΔT_C), valve location is the dominant factor, contributing 80.27% of the variation, followed by inlet pressure at 19.19%.</p>