Instruction manual
60 KOMAC00607-09EN 
System Maintenance 
General 
On initial start-up 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. A recommended 
maintenance schedule is located at the end of this section. 
A Periodic Maintenance Log is located at the end of this manual. It is suggested that the log be 
copied and a report be completed on a regular basis. The log will serve as a useful tool for a 
service technician in the event service is required. 
Initial start-up date, vibration readings, compressor megger readings and oil analysis 
information should be kept for reference base-line data. 
Compressor Maintenance 
The semi-hermetic compressor requires no yearly scheduled maintenance. Compressor 
vibration is an indicator of a possible problem requiring maintenance. It is recommended that 
the compressor be checked with a vibration analyzer at, or shortly after, start-up and again on an 
annual basis. The load should be maintained as closely as possible to the load of the original 
test. The initial vibration analyzer test provides a benchmark of the compressor, and when 
performed routinely, can give a warning of impending problems. 
Lubrication 
No routine lubrication is required on AWS units. The fan motor bearings are permanently 
lubricated. No further lubrication is required. Excessive fan motor bearing noise is an 
indication of a potential bearing failure. 
Compressor oil must be ICI RL68HB, McQuay Part Number 735030446 in a 1-gallon 
container. This is synthetic polyolester oil with anti-wear additives and is highly hygroscopic.  
Care must be taken to minimize exposure of the oil to air when charging oil into the system. 
The oil charge is 6 gallons (23 liters) for all compressor sizes. 
Oil Filter Removal and Renewal 
Fitting a New Oil Filter Element – Dismantling 
Prior to this procedure, pump out the compressor; isolate the electrical supply to the control panels 
and compressor motor terminal. 
!
WARNING 
After the compressor has been pumped down and isolated, the oil contained inside the filter 
housing will remain hot enough to cause burns for some time afterwards. Always allow 
sufficient time for the oil to cool down so that it is cool enough not to be a danger when 
drained off (less than 35 °C is recommended). 










