How often would you change the compressor oil for a air cooled chiller?

Hi
Sorry if this has been asked before I cannot find the question. We have a Carrier 30XA chiller and I cannot find in the manual if there is a time period (hrs)to replace the compressor oil. Is there such a recommendation, if not I would value peoples views on this from experience?

Kind Regards
ivan

I operate on an annual oil sample regime rather than replacement of oil.
A refrigerant system is a closed system with oil systems protected with filters (driers) the biggest failure of oils is due to moisture content increase and this is only from opening closed systems or introduction of contaminants.

With an annual oil sample you can detect increasing levels of contaminants, water metals etc. you are minimising intrusion into the system and minimising leakage and induced contaminants. while still monitoring condition.

Thanks for the quick and very practical response that makes perfect sense to me

Hi ,
It depends on the oil type and stability, I would go for hours count oil replacement, oil looses its characteristics gradually with working hours (in addition to the contamination that can occur).
Better to search for the manufacturers recommendation .
e.g: frascold screw compressors requires oil replacement at the first 1000 hours, than each 10000 hours of operation.

Dear Friends,

Regarding this topic I have a question. When you buy a fridge for your home, Maybe fridge are working for years during 24h of day, Do you change oil of compressor after a time ?
I think until you have not problem on your system , for example burning compressor or leak on system and …. It is not necessary to change oil.

Some metals effect on oil much more than others, For example iron is one of important metals that effect on mixture of "refrigerant + oil" instead copper.
By this you see that at ammonia systems that all of pipes and valves are made form iron, It is necessary to change oil after a period of time but at for example R22 systems it is not necessary I think because most of valves and pipes are made form copper and brass.

Find Sporaln document at attachment regarding oil and filter drier.

Sincerely yours.