The mini-split in electrical room 2A was checked today. During maintenance it was discovered that there was an error code displayed and the system was not operating. During diagnostics today the error code was confirmed, researched and the causes were ruled out today. The system was operated and monitored once the error code was cleared. In addition to this I cycled the system from cooling to off 4 times in an effort to recreate the error. This system is a cool only system and returned to cooling today after being reset. All causes for the error code were ruled out one by one today. The thermostat was left on 85deg and the room temp dropped 5 degrees during the runtime today. Today’s temp is 73 and the room temp was 90 when I started. Information of the unit was documented. This system is back in service. Thank you, Jon Tech notes Mitsubishi mini-split system M/n PKA-A12-AA6. S/n 5ZA05459A Located inside electrical room 2nd floor west wing and on the west roof.