When a failed air conditioning compressor is replaced by a new a/c compressor, it is so important to have the lubricant
distributed evenly across the air conditioning compressor and the a/c system before engaging the system for the first
If this is overlooked and the air con compressor is engaged immediately after is has been charged with
refrigerant, it may happen that all the oil in the a/c compressor will be pushed out all at once while there
is no oil yet to enter the air conditioning compressor on the other side. This is caused by the fact that it takes some
time for the oil to spread across the system and mix with the refrigerant. Eventually the ac compressor
may be damaged because of a lack of lubrication during the first few minutes of operation.
This will of course be more problematic after the system has been flushed, this will mainly be the
case after the air con compressor has suffered a catastrophic failure with metal particles from the a/c compressor
being spread across the entire system.
A rule of thumb guide when installing a new air con compressor is to manually turn the a/c compressor pulley
to make sure that the oil is distributed through the air con compressor evenly. Experienced engineers will
normally turn the ac compressor 10—15 times to ensure that oil has been pushed around the system.
There is still more to do to prepare the air con compressor, knowing and following the procedure will be of
great importance if a newly installed air conditioning compressor should fail after a short period of time and within
its warranty period. There is no bigger disappointment than having a warranty claim denied because
something as simple as the following procedure has been overlooked.
Generally new a/c compressors are supplied charged with oil, but it is always recommended that you
check this by draining the new air con compressor to check the amount of oil in the air conditioning compressor.
Then once you have removed the old a/c compressor you should do the same again, empty the old ac compressor
of oil to see how much oil was in it and then fill the new air con compressor with the same amount
this is to avoid over charging the system with oil.
1, Open all air louvers at the dash board, 2, Start the engine and let it stabilise at idle speed 3, Set the
blower at maximum speed, 4, Engage the a/c system and operate it continuously for 2 minutes at below
After the two minutes the air con compressor oil will have distributed evenly throughout the a/c system.