AC Diagnostic System: main Refrigerant Type R22 Metering Device-TXV SP/HP Not operational SLT/LLT VSAT/LSAT SH/SC Outdoor Entering Air Temperature 86 Returned tstat to original settings: Y Unit operational; prior to leaving: N Notes: Arrived to unit with power off at the thermostat. Turned unit on, checked outside unit and found refrigerant levels extremely low, this is the cause for the compressor not turning on, the low pressure switch is activating to keep that compressor from overheating. Mr.Ryherd will add refrigerant from his personal R22 jug, he did ask me what the target subcooling is and i informed him he should be looking for around 10 subcooling, recommend pouring some water over the compressor before trying to turn it on. Due to the age of the system and cost of R22 these days, recommend to start looking at replacement options, offered to schedule a comfort advisor to come out and give a free estimate and they have decided to call on there own time to schedule for a com