I performed a heating maintenance on two units one in the attic is a heat pump air handler I replaced the 20x25x5 filter I checked all electrical components and checked the temp rise and checked the Freon levels and checked the capacitor and the basement unit is a gas furnace Ac unit I did not replaced the 16x25x5 homeowner I checked the temp rise and checked all electrical components and checked the gas pressures and checked the heat exchangers and checked and cleaned the flame sensor both units are in good working order at this time