The current air quality is one of the issues that must be addressed. The need of oxygen-rich air cannot be overstated. Clean air is becoming a need for human activities. The standard for temperature quality in inpatient rooms is the temperature parameter 22-23℃. This study aims to overcome the distribution of airflow. This type of research uses a descriptive method based on functionality analysis using Computational Fluid Dynamics (CFD). This study uses an HVAC system with variations in geometry, duct position, and cooling time to measure the temperature in the inpatient room. The results showed that if the model of the inpatient room at Bitung Hospital, variations in the location and geometry of the duct. The location of the inlet and outlet diffuser must be on the upper side of the wall, so that it can overcome the temperature of the inpatient room in the hospital. The alternative solution is produced that can increase the maximum thermal comfort for patients at Bitung Hospital. In the result section two geometry get that where thermal comfort is good for patient.