I only have a 2010 Prius but during 90+F, high humidity, I noticed the A/C compressor was making a noticeable buzz outside of the car. I only heard it because I had to jump out of to help my wife but I hadn't noticed it before. As I walked around the car, the compressor noise seemed to be uniform and omni directional. Yet as soon as I sat in the cabin, it was muted. If I rolled down a window, I could hear it echo off the wall. Have any current or former NHW20 owners noticed the A/C compressor noise? What surprised me is I thought we had a scroll compressor. These things are supposed to be very quiet. So hearing the compressor didn't make a lot of sense. Bob Wilson
I haven't noticed anything, but I haven't walked around the car listening for a sound, either. I'll look for it at the next opportunity. You said it has a "buzz" sound -- How do you know it is the A/C compressor?
When the hot weather returns, I'll double check but I didn't hear air noise like a fan might make. We have just rain today but when the hot weather returns, I'll re-run the test ... shoot looks like a couple of days of rain. Bob Wilson
A scroll compressor is still a cyclic device. See the animation I dug up off the net somewhere, and note that it's pushing a new quantity of refrigerant out the center hole every time it goes around. It's not a turbine. . You also have whatever noise the 3-phase motor and the scroll eccentric mechanicals make and as much switching whine as comes from the inverter, so all told it's not going to be dead-silent. You've heard the a/c system in the second-gen cars too, right? . _H*
Bob, I just bought my 2010 Prius Saturday. During test drives I never noticed this sound. My wife an I drove it all around town all day Sunday and, again, I noticed no unusual sounds. But when we pulled into our garage I heard this loud buzzing that I swear I had never heard before. I got out of the car and it was quite loud, coming from under the hood. When I shut off the A/C it went away. Since then, I have noticed that the sound comes and goes. Now and then I will stop the car, get out and listen, and it is gone. I should also mention that I live in Florida and it is 94 out and very humid. I took the car to the dealer and had a technician listen to it. He claims it is a "normal" sound. At first I was concerned, but I have seen enough posts here that I believe he may be right. This just may be a normal sound I have never noticed before in my excitement. After you buy a car, you start looking and listening a lot closer than you did before. I'd be curious to know if the sound in your car comes and goes like mine. That's what the technician said it would do. Is yours always buzzing, or does it quiet down at times.
In addition to the flow noise described by hobbit, Oldham coupling in a scroll compressor produces some unbalance, so there is always a little vibration. Tom
Hi all, The compressor for our prius's is one of a kind. Keep in mind, the prius's gas engine does not run continuosly, so, if AC is to work in a car like ours, a compressor that can run on its own is needed. I have a 2015 and I absolutely love this car! I had a 2006 scion for 9 years with the only issues being replacing the water pump. The scion still had the original freon in it when I sold it! Anyway, with my prius, I have researched the compressor and it is scientifically phenominal. It runs by temperature needs. So, if it is over 90 degrees outside and you turn on the AC, the compressor may run on its own to bring up the necessary pressure to cool the cabin. It is a variable speed, so this allows the compressor to run entirely on its own. The initial noise will be louder the hotter it is at start up with the AC button on. As you drive, and the pressure builds, it will quite down. Mine started making noises when the weather got extemely hot. We are currently in a heat wave (over 95 degrees daily, sometimes over 100) and my compressor started making noises. Needless to say I was not happy as I have only 1500 miles on my car. But after swarming the internet and googling all over the place, I was pleased to find out about this variable compressor. Just like everything else on this car, it runs only as needed, and runs harder if necessary. The compressor is one of a kind, so I do imagine if a repair is needed, it may cost a little. That is why I opted for extra coverage on my warranty. Ok, thats my two cents. Just wanted all to know the 411 on the noise issue. New to this site and will frequently as needed.
I hadn't noticed the noise until I recently replaced the condenser and recharged the system. Was worried I did something wrong so good to hear others hear the exact same buzz noise without doing any work. On a side note an extended warranty won't necessarily cover AC. If the dealer decides something external caused a problem your warranty will be worthless. I find this out the hard way when the dealer wanted $1000 to repair my AC while the car was under warranty because a rock supposedly hit my consdenser. Luckily I ended up being able to replace the condenser and recharge the system for about $100 with a couple hours of my time. Total amateur using youtube here, but dealer claimed it was a 5.5 hour job.
