Yes, you need professional equipment. You need a vacuum pump to draw out all the air from the system. There are 2 switches in the system that will not allow the compressor to run. One is low pressure, the other is high pressure. Once the system pressure builds to about 20-30 pounds, the compressor will come on. It will cycle off and on for awhile until the system is fully charged. If it does not start with pressure on the system, the compressor relay is bad.