I bought a new goodman AC/heat pump unit got it all installed and wired the inside unit fan runs great but the condensing unit fan and pump will not run after the timer goes off the condensing unit has an electrical hum but it won't start?? any idea what going on ?

I think the sound is 24 volts powering the contactor, but without 240 volts properly connected, or possibly turned on, it will not run.