Performed preventative maintenance on a Lennox AC system. Model number: XC14-030-230A10, serial number: 5816D04758. Upon arrival the unit was on. I adjusted the temperature on the thermostat so the system would keep running. Went up in the attic and watched the unit run. Turned the unit off at the switch. Removed the panel to the evaporator coil. Inspected the coils for any dust build up. Poured water into the condensate trap and watched it drain out properly. Poured water into the condensate gravity drain and watched it drain properly. Removed the panels to the furnace. Checked the blower motor and fan for any dust build up. Replaced the 16x25x1 filter. Checked all electrical connections to make sure they were secure. Took an amp draw for the motor. Running within the manufacture’s specs. Placed the panels back on the unit and watched it run. Went outside to the condenser. Checked the coils for any dirt build up. Coils are pretty dirty and I recommend a cleaning. Removed the panel and