Residential customer in Plano service call and Upon arrival found system not cooling well. Checked indoor unit and found equipment operating properly. Checked outdoor unit and found that the refrigerant levels were low in the system. Homeowner has had to add refrigerant to the system before. Evaporator coil is under warranty and homeowner would like to move forward with replacing the warranty coil. Homeowner also wanted to go ahead and add refrigerant to the system. Ordered coil through Lennox in Allen and coil is in stock. Order#34441855 will be at Lennox in Allen by tomorrow morning.