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Electric AC compressor noise

Discussion in 'Gen 3 Prius Technical Discussion' started by Randyhmptn, Jul 8, 2020.

  1. Randyhmptn

    Randyhmptn New Member

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    Hi all. I'm noticing that my 2010 Prius 3 has this somewhat loud "whirring" sound coming from the AC compressor when the temp outside is high. Mid 90's. Is it normal to make this sound? This is the first year I've had it during summer time in the south and just wanted to make sure it's normal.
     
  2. Blake2100

    Blake2100 Junior Member

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    Mine does the same I believe it's normal
     
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  3. bisco

    bisco cookie crumbler

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    they are quite noisy, and the higher the fan, the faster they run, and noisier they get.


    but they can get noisier and explode at some point. there's just no way to know.
     
  4. ChapmanF

    ChapmanF Senior Member

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    @lech auto air conditionin has recently posted that there may indeed be a way to know, at least to know when the system is undercharged and the compressor is working too hot.

    Simple measurement of the discharge tube pressure.

    I'm going to measure mine as soon as I find one of those round tuits.
     
  5. Grit

    Grit Senior Member

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    They should have printed that in the manual also.
     
  6. lech auto air conditionin

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    not that simple, much more then that. just like sight glass it can change and if there is a air flow problem, expansion valve not metering correctly, too much oil in the system, is the condenser fans working to their full potential.

    Discharge temp is just one measurement. using it alone may lead you down a rabbit hole. but it is a good simple DIY reference. Oh yea if you do not have a vary good clamp on contact temp sensor you will not get a accurate temp.
     
  7. lech auto air conditionin

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    Yes they get much louder on 90F + days. But every one perception of sound is different.
     
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  8. ChapmanF

    ChapmanF Senior Member

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    In your video on the discharge temp observation, what was the difference in degrees between the first measurement and the after-repair measurement?
     
  9. lech auto air conditionin

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    Don’t remember I’ve done too many cars since that one I’m gonna have to remake that video and show it on another car. I think one of my videos that I posted on YouTube on my channel shows a bus electric compressor that was extremely low on refrigerant the temperature I believe was somewhere around 300° that’s a worst-case scenario burn out but it was still running.
    Different systems react differently as do different compressors they’re not all created and they do not operate equally like some people have been told and taught to believe. This is facts measurable not fiction or religion.
    I have some compressors when they’re low on refrigerant they’ll be about 140° plus an after recharge their case will be less than ambient temperature in some conditions even cold like 50° because they got ample sub cooling of refrigerant flooding back aerosol into the compressor cooling it off. But not liquid