On initial startup and periodically during operation, it will be necessary to perform certain routine service checks. Among these are checking the liquid line sight glasses, and the compressor oil level sight glass. In addition, check the MicroTech® III controller temperature and pressure readings with gauges and thermometers to see that the unit has normal condensing and suction pressure and superheat and subcooling readings.
Initial startup date, vibration readings, and oil analysis information should be kept for reference base-line data
If the service technician has determined that the refrigerant charge has been contaminated, the charge should be recovered and tested for contaminates or noncondensables. Appropriate actions should be taken based on testing and Clean Air Act regulations.
Source: Daikin (oslo.daikinapplied.com)