AUTOMATED REFRIGERANT CHARGE STATION FOR PROTABLE MEDICAL REFRIGERATORS

Abstract

Refrigerant is used widely for maintaining the desired temperature of vaccines, food, and living spaces; However, as the grams of refrigerant a system requires is decreased, the required precision of refrigerant charging is increased, improved methods of supplying refrigerant must be developed to ensure proper operation and efficiency. Providing an accurate refrigerant quantity to any cooling system is critical. Most known methods of refrigerant delivery are done manually, introducing the potential for human error in the refrigerant delivery process. This design improves refrigerant delivery accuracy by automating the refrigerant recharge process and monitoring refrigerant mass. A refrigerant recharging process system was designed and built by the team using electronically controlled pumps, valves, and sensors. The system minimizes human involvement and maintains an accuracy of 40g ±0.10g of refrigerant during delivery. The monitoring system consists of load-cell based weighing stations that continuously collect data on the mass of the refrigerant tanks and medical refrigerator. The system alerts operators of events, such as empty refrigerant tanks needing to be switched out or full recovery tanks of excess refrigerant, ready to be handed off to a third party for recycling.