What was found
WITH APU RUNNING ON GROUND, COCKPIT PAC SELECTED OFF, CABIN PAC ON HIGH AND APU BLEED SELECTED TO HIGH FLOW, SMOKE ENTERED COCKPIT THROUGH WEMACS. COCKPIT TEMP SUPPLY STAYED AROUND 160 DEGREES & DIDN'T STABILIZE. INSTALLED 1 EA REPAIRED ACM IAW MM 21-51-00. PERFORMED SYS OPS CHECK IAW MM 21-57-00. OPS CHECKS AND LEAK CHECKS GOOD. INCLUDED IN INSTALLATION IS 1 EA COCKPIT WATER SEPARATOR SOCK (NEW) PN 746451-3.