New install customer concerned about unit not cooling properly. Customer has mentioned the nest thermostat is not connected to WiFi and not cooling properly. Checked thermostat calibration and filter location. The thermostat is weak battery and not connected to WiFi. Checked air handler unit and checked safety float switch and inspected drain line. The safety float switch is tripped with water and drain line is clogged. Strongly recommend drain solvent to clean and clear blockage in the drain line. Explained to customer that the drain line is existing prior to install. Still have alge or debris in the drain line. Recommend taps membership to annual preventative maintenance inspections on ac system. Customer has approved for drain line solvent and new taps membership. Added drain solvent to the drain line and flushed drain line with hot water. Primed drain line and checked unit operation. Located the nest thermostat is blank and unit has stopped working. Located the thermostat has i