What was found
AT FL 380 IN THE CLIMB, TWO LOUD BANGS, EMER PRESS & ACM OVHT LIGHT CAME ON. CABIN WAS -3700 FPM. STARTED EMER DECENT, AFTER 1 MIN CABIN STARTED PRESSURIZING. THEN THE PROCESS REPEATED ITSELF. PLACED BOTH 410° & 450° ACM OVER TEMP SWITCHES ON ORDER FOR SUPPORT. WHILE TROUBLESHOOTING OPENED LT PC BOARD BOX, PC BOARDS LOOK FINE, CHECKED AIR WATER SEPARATOR & CLEANED SOCK, NOTED THAT THE SOCK WAS CLEAN, DRAIN WAS CLEAR & PRESS VLV WAS IN GOOD OPERATING CONDITION. REMOVED THE 410 ACM OVER TEMP SWITCH & OPERATIONS CHECK HAD SCATTERED RESULTS. REMOVED BOTH OVERHEAT THERMAL SWITCHES & REPLACED WITH NEW SWITCHES. RAN ACFT, OPS CHECK GOOD ON ENVIRONMENTAL SYS, PRESSURIZATION SYS & EMER PRESSURIZATION SYS. LEAK CHECK & OPS CHECK GOOD ON ALL SWITCHES. WORK DONE IAW MM CHAPTER 21-11-00. CLOSED PANEL AFT OF ECU.