How to Remove Excess Refrigerant Oil?

[OLeah]

Adopt the method of repeatedly replacing the new refrigerant to reduce the oil content in the system. Weld open the exhaust pipe of the compressor and pour it out directly. If the refrigerant is excessive, simply release an appropriate amount.

[MacManuel]

Last time my car's A/C cooling performance deteriorated, the mechanic said there was too much refrigerant oil added. To remove the excess oil, the safest method is to go to a professional repair shop where they can use a dedicated recovery machine. They'll first vacuum and recover the refrigerant, then use equipment to separate out the excess oil, before finally performing a precise measured recharge. I once tried using a syringe to extract oil from the low-pressure line myself, but ended up introducing air into the system which caused unstable pressure, costing me more money to repair the lines. Now I understand - this isn't a job where you should try to save money by DIY. A deviation of just 20ml in oil quantity could cause the compressor to fail prematurely. It's much safer to leave it to professional equipment.

[OIris]

As an experienced DIY car enthusiast, I've encountered situations where the refrigeration oil was overfilled. A simple method is to run the AC for 5 minutes to circulate the compressor, then locate the Schrader valve at the low-pressure service port and slowly drain the mixed fluid into a transparent container using a dedicated oil extraction tube. After observing the separation of oil and refrigerant, you can estimate the amount drained. Important precautions: Always wear safety goggles to prevent splashes, and the ambient temperature should ideally be around 20°C. After draining, use an electronic scale to measure the refrigerant recharge amount - getting this step wrong means the entire system would need to be vacuumed again, which is particularly troublesome.

[OwenLee]

Excessive refrigerant oil can reduce cooling efficiency and damage the compressor. To remove the excess oil, a refrigerant recovery and recharge machine must be used. After the technician connects the high and low-pressure hoses, the machine first recovers the refrigerant, and the oil is automatically separated in the oil separator and collected in the oil storage bottle. I watched as the technician used a measuring stick to check the oil level in the tank and precisely drained the excess. The key is to measure the compressor oil level before and after the operation—some vehicles require removing the dryer bottle to get an accurate reading. The entire process takes less than half an hour and costs around 100 yuan, which is much more cost-effective than replacing the compressor.

[LucyMarie]

I've seen cases where apprentices added the wrong amount of refrigerant oil during car repairs. There are actually two methods for draining it: If the compressor hasn't been started after the wrong addition, you can simply open the receiver-drier to pour out the excess oil. If the system has already circulated, you'll need to use a recovery machine with oil separation function. The key is to record the original filling amount, and never mix PAG oil with POE oil as different vehicle models require different types. Last time when helping a neighbor, I found his car used No. 46 refrigerant oil - using the wrong type can cause sludge to clog the expansion valve, so after draining, you must also check oil compatibility.

[HaileyFitz]

Last maintenance, the apprentice overfilled the refrigerant oil. The technician taught me an emergency DIY fix: First, run the AC at maximum for 10 minutes, then turn off the engine to let the system depressurize. Locate the low-pressure pipe connection, loosen the drain screw, and place an oil catch pan underneath to slowly drain the fluid. For every 50ml drained, run the AC for 2 minutes to circulate the new oil. Repeating this process three times should sufficiently reduce the oil level. However, prepare an electronic scale to measure the total amount drained, as operational errors may cause refrigerant loss. Finally, the technician reminded me to replace the receiver-drier, stating that contaminated desiccant could damage the new compressor.