A start assist kit is designed to assist your compressor on start-up. If your inside air conditioning coil is located more than 50 feet from your outside condensing unit, you probably need a start assist kit to assist your compressor when it turns on. You see, your air conditioner works like a pump circulating the refrigerant throughout your system. The harder the pump has to work the less efficient it is and the more likely it is to break down. A start assist kit helps your air conditioner when it needs help most, when it first starts up and has to begin the pumping process. The addition of a start assist kit will extend the life of your compressor, which could save you from the high cost of a repair or replacement.