After repairing it is necessary test for refrigerant leaks in the system.

If there are no leaks, it is necessary to flush out the system to clean the inside circuit and remove all the oil inside the system. Synthetic lubricants are hygroscopic. Once a system is exposed to the atmosphere for more than 15 minutes, all the oil in the system need to be taken out. (Can use KT-007 flushing machine to remove all the oil in the system)

The amount of oil present in the car ac system is very low.

It cannot be varied significantly. There is no way to ascertain how much oil is in the system.

Only way is to take out all the oil first. Then add the recommended quantity of oil by the manufacturer. If we try to replenish oil without taking out the oil inside the circuit, oil quantity in the system will be either high or low. If it is low the compressor will fail soon.

If the oil level is high, it will work as an insulation and reduce the cooling effect.

Oil should be charged to the evacuated system. (If oil is charge before the evacuation, moisture in the system will be absorbed to the oil.)

After evacuation the system, Oil must be charged with a graduated oil gun.

Refrigerant need to be charged according to the weight given by the manufacturer.

Vehicle manufacturer has recommended to charge refrigerant by weight.

But not by pressure,

After charging, system performance needs to be checked with pressure temperature analyser.

It will be help full to confirm that the system is working properly or not.

This label stick to the car will show the recommended volume of oil and the weight of the refrigerant.