How to add refrigerant oil to an automotive compressor?
2 Answers
Automobile manufacturers have different specifications for refrigerant oil filling quantities. Before refilling, it is essential to measure the residual oil from the old compressor by pouring it into a graduated cylinder. A reference quantity of 100-150 milliliters is typically recorded. The oil temperature should generally be maintained between 45~60℃, with the maximum not exceeding 70℃, and remain stable. If the oil temperature continuously fluctuates and rises slowly, it indicates a malfunction.
I remember one time I tried to add some refrigerant oil to my car because the air conditioning wasn’t cooling well. Refrigerant oil is used to lubricate the compressor in the AC system, and not replenishing it can cause the machine to wear out. Here’s how I did it: First, I released a bit of pressure from the AC system and used a pressure gauge to locate the low-pressure port, which is usually near the compressor. I bought a bottle of the right type of refrigerant oil, like PAG oil, making sure not to get the wrong one. Then, using a professional syringe tool, I slowly injected the oil, strictly following the manual’s instructions on the amount—never too much, or the system could malfunction. That time, I went through a lot of effort doing it myself, spending a few dozen bucks on tools bought online, and almost ended up with an oil leak, requiring a redo. I’d suggest that unless you’re familiar with car repairs, it’s better not to DIY and just spend some money at a reliable auto shop for peace of mind. For regular maintenance, it’s recommended to check the refrigerant oil condition once a year to avoid delays.
