My central Air Conditioning compressor will not turn on. I can get the compressor to turn on by holding the contacts down on the unit. The unit runs fine and cool air comes out and the pipe from the unit turns ice cold so I don't think it's a freon charge or a leaking unit. Can it be the starting solenoid or some other wiring?

My central Air Conditioning compressor will not turn on. I can get the compressor to turn on by holding the contacts down on the unit. The unit runs fine and cool air comes out and the pipe from the unit turns ice cold so I don't think it's a freon charge or a leaking unit. Can it be the starting solenoid or some other wiring?

You are missing the low voltage signal that kicks in the contactor that has the contacts on it or the contactor is defective. Gey out you volt meter and check back on your 24 volt supply for the contactor with the thermostat calling for cooling. NOTE Kill the disconnect power for the 220/240 volts outside first for safety. The 24 volts is generated by the unit inside.