Bob and Tim are at a job where a customer has damaged a refrigerant line on a heat pump. When they arrive, the line is still blowing a slight amount of vapor from the split in the line. They install gauges and the system is at 0 psig. The refrigerant is R-22. They get the torch and braze the refrigerant leak closed. There is no need for a vacuum because the leak was repaired before any air had time to enter the system. It is 35 degrees outside, and they now must charge the unit. There is no charging chart in the unit so they are going to need to improvise.
“How are we going to get an accurate charge into the system with no chart?" asked Tim.