[77newell]

Thank heaven I already have the torch. I expect the service call plus the previous call to total $400 labor and the refrigerant another $100 or so. The tools aren't that much more than that, though I'd have to buy the R22.

Here are the temperatures/pressures I found online for R22

Temp PSI
60 102
70 122
80 144
90 168
100 196
110 226
120 260
130 297
140 337
150 382

According to what I recall from my engineering days (which were long enough ago I could be all wet), the temperature in the condenser where the bulk of the vapor condenses would determine the pressure on the high pressure side of the compressor. Since we were operating at about 67 degrees ambient air temperature that aligns pretty well with the 130ish pressure I recall we had. Since there will be losses (rises in temperature as you work from outside to inside) due to the transfer coefficients between the air and the fins, between the fins and the tubes, and between the tubes and the vapor, the actual temperature inside the condensing tubes will be higher than ambient, but I would not have thought it would be on the order of 60-70 degrees. There may be other variables that I'm not taking into account, but when this thinking jived with the service manager's off-the-cuff reaction that the pressure made sense given the cool day I convinced myself I was at least in the ballpark.

Richard, it's always good to hear from you. Your expertise far exceeds my own. And besides, you have better tools.