CAUTION: This operation must be performed by a specialist.
When replacing any cooling elements in the air conditioning system, it is necessary to completely pump out all the refrigerant from the system.
With the ignition on, remove the safety cap from the low-side service fitting on the accumulator and connect a charging station or equivalent test rig. If you are not using a charging station or equivalent, begin to drain the system by slowly connecting a hydrometer hose to the low-side service fitting on the accumulator and draining the coolant into the oil bottle. The hose will slowly tighten onto the valve and coolant will begin to drain from the system into the container. If coolant does not drain from the system, check the operation of the valve depressor in the hose fitting.
Once the low pressure side of the system has been completely relieved, check to see if any pressure remains in the high pressure side fitting on the fluid supply line.
1 - adapter; 2 - hydrometric hose; 3 - oil; 4 - open bottle of oil for draining the coolant; 5 - battery.
If pressure is detected, try to relieve the high pressure side using the same method as the low pressure side (This situation indicates that there is a restriction on the high pressure side and the cause must be determined and corrected before evacuating and charging the system).
When the system is completely drained (the valve is fully seated and there is no steam leakage), measure the amount of oil drained and record the result.
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If the measured amount is 15 ml or more, the same amount of new 525 viscosity refrigerant oil must be added to the system, plus some extra for replacement parts, before the system is evacuated and recharged with refrigerant.
Topping up the air conditioning system with oil
Adding oil to the air conditioning system should be done after unloading, but before pumping out the system as follows:
Remove the coolant suction hose at the battery outlet pipe connector.
Pour the correct amount of new cooling oil into the hose or pipe, and then reconnect the hose to the pipe correctly.