This study investigates the preliminary performance of a CO₂ heat pump dryer system with an open-loop air cycle, offering a simplified and energy-efficient alternative to conventional drying technologies. The open-loop cycle has been proposed in this study, with its working principles illustrated in the psychrometric chart. Through numerical analysis, the system demonstrates stable thermodynamic performance, with the gas cooler effectively heating air to 41.8–50.8 °C with the airflow 0.5–1 kg/s. The simulation results reveal that lower air mass flow rates (0.5 kg/s) optimize drying performance, yielding faster moisture removal (57.54 min for 5 kg moisture) and higher energy efficiency (SMER = 0.37 kg/kWh). In contrast, higher flow rates (1.0 kg/s) prolong drying times (102.73 min) and reduce efficiency (SMER = 0.21 kg/kWh) due to reduced dehumidification effectiveness. The open-loop system can simplify the complicated piping, making it cheaper and easier to install while still working well in various weather conditions. This research shows the potential of the system that can save energy without being overly complex, making it a competent option for eco-friendly drying solutions. With this as a baseline, future research can focus on comparative analyses between open-loops (with dry and wet outlets) and closed-loop cycle to further optimize performance and broaden applicability.