Using this Frick Quantum Rotary Screw Compressor Unit is straightforward. First, make sure it's properly installed in your commercial refrigeration system according to the dimensions we've provided. Since it's a used unit that needs some maintenance, check the flanged pipe that was cut with a plasma torch. You'll need to repair it before starting to use the unit. As for the scratches and scuffs, they're normal and won't affect the main function, but keep an eye on them. When running the unit, ensure it gets the right power supply of 50 HP, 60 Hz, and 3 - phase. Regularly check the refrigerant levels, as it uses R717 Ammonia. If you notice any unusual noises or performance issues, it might be time for more in - depth maintenance. Remember, this unit is untested, so test it carefully under supervision before full - scale operation. Also, pick it up locally at the MSU Surplus Store as per the pickup details.