I recently had to do a repair on a roof AC on an RV. The unit quit blowing cold air. I checked the electrics and determined that the compressor was running. I had to add service ports to determine pressures. I prefer Robinair line taps and installed them on vertical runs of line to minimize the amount of oil loss. I measured zero pressure in the system. I hooked up the R22 bottle to check the line taps and see if they were actually working, they were. I found a small amount of oil on the outside of the lines and on closer inspection and removal of insulating foam found where two lines had been touching and eroded each other. Soap bubbles confirmed a leak at that point. I cleaned and soldered the leak. I pressurized the system slightly to check my patch with bubbles and found no leak. I pulled a vacuum and recharged the system. While the vacuum pump was running I cleaned the condenser coils. I did not have access to adequate temperature gauges or charging information so I had to "wing it". I charged the system until the whole surface of the evaporator was producing condensation. The system has been performing well for a couple weeks since the repair.

This is the short story and there are many other considerations that went into this simple repair.

06/15/2006 - System is still working great and is very appreciated.