[mycbarnes]

Hi Richard
To recharge them I use the super heat method. It requires a wet bulb thermometer, measure incoming air temp to evaporator, outside air temp, a standard set of service gauges and a thermocouple clamp temp sensor on a Freon copper line. With proper chart, known temps, you can get it spot on proper. I also have a ultrasonic gauge that can determine if bubbles like a sight glass would, but the super heat method is better.
Terry