Arrived at location on 7/9/21 - Upon arrival the box was reading 6 degrees on the controller display. Customer states that he wasn't happy with the reading he was getting from his thermometer and that there was water on the bottom. Upon inspection the unit's evaporator was iced up. The defrost operation was checked and the heater does pull amperage. Both evaporator fans are running. The coil was de iced. Some defrost parameters were changed to help prevent this problem from occurring again. The box pulled down to -7 and cycled back on at -1 all is well.