While completing the annual maintenance. It was found that the system was low on refrigerant. After discussing with homeowner and her excepting the suggestion, I weighed in 2 1/2 pounds of refrigerant back into the system based on the superheat and sub cool value. After weighing the refrigerant I created the estimate. While on maintenance I checked pressures, amp draw in capacitance. I checked voltage, temperature Differential, amp draw on indoor fan and heater strip. I also replaced the electrostatic filter that customer had because it was due. Customer was double filtering. Removed all the dirty filters out of the ceiling return grills and wall return grills. Currently only one filter is at the unit. System is on cooling properly at this time. Sent estimate for electronic leak search, also sent estimate for closing all the openings around the 5 to 6 supply grills in her home.