The compressor protects itself - by going into "lock out" and there isn't anything you can do about it till it cools down - patience is a virtue. You could turn on either the heat or the fan to help speed it up.
Run the fan only and it will thaw, usually in a few hours unless it is really iced up that would take overnight. Then have it checked out and the reason it froze corrected.
unplug it and let it thaw. The vent could be frozen over.
what causes compressor lockout in voager rooftop unit.
The ac compressorThe ac compressor
pressure switch located on the accumulator
The ac compressor pump may be seized.
No oil in compressor - wether it works or not, it still needs that special ac oil -
Look for how it is attached and remove the needed fastners or components. No majic unfortunately.
Bad clutch on compressor, unplug the wires from the AC compressor, replace fuse if doesnt blow fuse its in compressor, if blows then gounded wire
Improperly programmed programmable thermostat.
Make sure the AC isn't over-filled.
Check for a slipping drive belt between encine crank pulley and AC compressor pulley.
Technicaly yes, but all you have to do is turn the unit off for about an hour and let it thaw. It will work properly again after that.