How to Add Refrigerant Oil to Car Air Conditioning?
1 Answers
There are three main methods for adding refrigerant oil to a car air conditioning compressor: direct addition, addition from the high-pressure side, and addition from the low-pressure side. The appropriate method should be chosen based on the actual situation. The specific procedures are as follows: 1. Direct Addition: If adding directly from the compressor, an oil return operation should be performed first. This involves running the compressor at idle speed with the control system set to the coldest and highest fan speed for 20-30 minutes to allow the oil to return to the compressor. Then, turn off the engine, release the refrigerant, remove the compressor from the vehicle, drain the old oil, and directly add or replenish new oil. 2. Addition from the High-Pressure Side: When adding from the high-pressure side, evacuate to 98 kPa, close the high-pressure side manual valve, and close the service valve on the compressor. Remove the high-pressure side hose from the gauge end and insert it into the refrigerant oil. Open the service valve to allow the refrigerant oil to be sucked into the system. Close the service valve immediately when the oil is nearly fully drawn to avoid sucking in air. Then, reattach the high-pressure hose to the gauge, open the high-pressure side manual valve, and continue evacuating before adding refrigerant. The engine and vacuum pump should not be running during this process. 3. Addition from the Low-Pressure Side: When adding from the low-pressure side, no service valve is needed. After evacuating to 98 kPa, close the low-pressure side manual valve while keeping the vacuum pump running. Keep the high-pressure side manual valve open, remove the low-pressure side hose from the gauge end, and insert it into the refrigerant oil to draw the oil. Once the oil is drawn, reattach the hose to its original position, open the low-pressure side manual valve, and continue evacuating before adding refrigerant. Note that too much refrigerant oil can impair cooling performance, while too little can damage the compressor. Always add the specified amount as per the vehicle's requirements.