Air Conditioning System Precautions (page 3 of 3)

GENERAL INFORMATION

03-31

Refrigerant oil

Refrigerant oil easily absorbs water and must not 
be stored for long periods. Do not pour unused 
refrigerant oil back into the container. Always 
use an approved refrigerant oil. 
 

 + 

 CAPACITIES, FLUIDS, LUBRICANTS 

AND SEALANTS, Lubrication.

When replacing components in the A/C system, 
drain the refrigerant oil from the component being 
replaced into a graduated container. On assembly, 
add the quantity of refrigerant oil drained to the new 
component.

Compressor

A new compressor is sealed and pressurised with 
Nitrogen gas. When fitting a new compressor, slowly 
release the sealing cap; gas pressure should be 
heard to vent as the seal is broken.

CAUTION: A new compressor should always be 
sealed and could be pressurised with nitrogen 
gas. To avoid possible oil loss, release the 
sealing cap(s) slowly. Do not remove the cap(s) 
until immediately prior to connecting the air 
conditioning pipes to the compressor.

Rapid refrigerant discharge

If the air conditioning system is involved in accident 
damage and the system is punctured, the refrigerant 
will discharge rapidly. The rapid discharge of 
refrigerant will also result in the loss of most of the oil 
from the system. The compressor must be removed 
and all the remaining oil in the compressor drained 
and refilled as instructed in the air conditioning 
section of this manual.

Precautions for refrigerant recovery, recycling 
and recharging 
When the air conditioning system is recharged, any 
existing refrigerant is first recovered from the system 
and  recycled. The system is then charged with the 
required weight of refrigerant and volume of 
refrigerant oil.

WARNING: Refrigerant must always be recycled 
before re-use to ensure that the purity of the 
refrigerant is high enough for safe use in the air 
conditioning system.

Recycling should always be carried out with 
equipment which is design certified by 
Underwriter Laboratory Inc. for compliance with 
SAE J1991. Other equipment may not recycle 
refrigerant to the required level of purity.

A R134a Refrigerant Recovery Recycling 
Recharging Station must not be used with any 
other type of refrigerant.

Refrigerant R134a from domestic and 
commercial sources must not be used in motor 
vehicle air conditioning systems.

CAUTION: The system must be evacuated 
immediately before recharging commences. 
Delay between evacuation and recharging is not 
permitted.

Air Conditioning Compressor Replacement
A new compressor is supplied filled with a full charge 
(X cm

3

) of refrigerant oil. 

 

 + 

 CAPACITIES, FLUIDS, LUBRICANTS 

AND SEALANTS, Capacities.A calculated quantity 
of oil must be drained from the new compressor 
before fitting. To calculate the quantity of oil to be 
drained:

1 Remove the drain plug from the old 

compressor.

2 Invert the compressor and gravity drain the oil 

into a calibrated measuring cylinder. Rotate the 
compressor clutch to ensure the compressor is 
completely drained.

3 Note the quantity of oil drained (Y cm

3

).

4 Calculate the quantity of oil to be drained from 

the new compressor using the following 
formula:

X cm

3

 — (Y cm

3

 + 20 cm

3

) = Q cm

3

5 Remove the drain plug from the new 

compressor and drain Q cm

3

 of oil. Fit and 

tighten the compressor drain plug.