Performed diagnostic on 3 head mini split system. Unit is not cooling efficiently. Started by washing condenser coil due to it being too dirty for accurate pressure readings. Gauged up to system and found unit low on refrigerant. Bubble tested condenser flare fittings, no visible leak. Refrigerant was added by another company last year so system has a leak somewhere in refrigeration cycle. Spoke to Chris about repair options, including pulling all heads off the wall and treating for leaks. Decided to go with immediate fix for now and see how long that holds up. Added approx 3 pounds r410A to system. All heads are now blowing cool air and working correctly. No warranty on refrigerant. System operational upon departure.