AC Diagnostic System: back room. Refrigerant Type R22/ Metering Device-Fixed Orifice SP/HP 43/98 SLT/LLT 75/81 VSAT/LSAT18/81 SH/SC53/0 Outdoor Entering Air Temperature 81 Filter Size(s)12x24x1 Returned tstat to original settings: N left it on fan Unit operational; prior to leaving: N return visit scheduled Notes: Customer stated that unit was not cooling but it was blowing air. Saw on Notes for previous tuneup the unit was low on refrigeration and customer did not want to do anything. Hooked up gauges and found refrigeration very low but before adding more refrigeration want to go inspect coil and saw coil frozen over the customer know we would have to come back tonight to add refrigeration so coil can unfreeze. Booked call for 6-10 Customer just wants to add refrigeration at this time Estimate on invoice is just a worst-case scenario refrigeration unit holds 3 1/2 ponds Recommendations: