Performed preventative maintenance for air conditioning/heat pump system. Replaced the standard air filter. Inspected all the electrical components. Made sure the gravity drain to sump pump was clear. Tested the temperature split between the supply and return. System is operating at a 19° differential. Tested the amp draw from the compressor, blower and fan motor. All were operating within the manufacturer spec. Air filter should be replaced once every 90 days. System is operating properly at this time.