Customer concerned about unit not cooling properly. Checked breaker and safety float switch and inspected drain line. Checked thermostat calibration and filter location. Customer replaced filter. Unit is cooling well and drains at this time. Customer approved for 1/2 preventative maintenance visit and (2) uv bulb replacement Performed preventative maintenance tune up. Checked blower motor operation and inspected evaporator coil condition. Checked safety float switch and inspected drain line. Cleaned vacuumed drain pan and drain line. Checked thermostat calibration and filter location. Customer replaced filter at this time. Checked condenser operation and rinse condenser coil. Checked refrigerant levels and check test start up components. Replace (2) 24 volt uv light stick probe to prevent biological growth in air handler and evaporator coil.