Performed inspection on one system upstairs for cooling. Checked all electrical and amperage. Checked blower wheel and evaporator coil are good. Checked blower motor capacitor. Unit does not have in-line safety or wet switch. Drain line does not have PVC tee. Checked thermostat. Customer stated back light turns on and off occasionally without it being touched. Thermostat is operating in both heat and cool. Checked capacitor, contactor, and pressures. System operating as should.