I changed the thermostat and now the compressor will not start, I have checked all of the wiring and gone through tech support but still have no AC, any idea on how or if there is a reset on this model Carrier?

Does anything work by thermostat? Bad Fuse maybe.
You need 24 volts to Compressor Contactor coil, if so, then be sure you have 240 volts in and out of contactor.
Does the fan work and not the compressor?

Checked the fuses, all good. No fan no compressor.