1637 A/C 1-2 COMP & COOLANT FAULT. ~~~~~ 1637 1-2 EVAP CHOKE REQUEST EVAP C/OUT. 1637 A/C 1-2 COMP & COOLANT FAULT.  FC 1637 A/c 1 HLPS2. Checked 1637 A/c 1-2 LP/HP no freon. Vacuum system & able to hold -30PSI. Charged freon LP/HP 20psi/200psi. Suspect evap unit choked. Raised OPS 20 to replace 1637 A/c 1 evap unit.  Kamarul/Aliff 45167