Service diagnostic found that the thermostat had failed and was not sending any signal to the system. I also found the drain line has some build up in it which could cause a clog in the future. The outdoor capacitor is below value as well. I spoke with the customer and he chose to do the immediate repair and have the thermostat replaced. I removed the old thermostat and installed a T1 thermostat. Programmed the thermostat and cycled power. Function tested the system and it is now operational. The temperature in the home went down 5 degrees while on site.