Arrived to no cool service call performed system evaluation. Found system frozen up solid. Unthawed unit. Found system low on r22 refrigerant. Spoke to customer at this time customer chose to add refrigerant to system. With customer approval I added 1lb 13 oz to system. System is cooling at this time. System is starting to show signs of age if becomes low on refrigerant in near future suggest leak repair or consider system replacement due to age and condition. System is cooling at this time.