Why are my fans running on high, endlessly?

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fivepyelane Author

Level 1

0 points

Why are my fans running on high, endlessly?

Here are my normal temps...

Here are my specs...

Tried SMC reset, PRAM reset, all the suggestions around the block.

Am I crazy?

d

iMac, OS X Yosemite (10.10.5)

Posted on Nov 24, 2015 6:21 PM

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Answer 1

a brody

Level 10

82,941 points

Nov 24, 2015 6:25 PM in response to fivepyelane

All those temperatures are normal. You can see the CPU get up to boiling point of water! Don't worry about temperatures reported inside. Apple has not released those temperatures for public consumption, and software used to alter the fans speed can actually make the Mac misbehave more than not having such software. If you are getting slowness, you should look towards other causes*:

http://www.macmaps.com/Macosxspeed.html

* Links to my pages may give me compensation.

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Answer 2

fivepyelane Author

Level 1

0 points

Nov 24, 2015 7:15 PM in response to a brody

I'm just trying to get my fans to run at their normal lower setting. The fan noise is intolerable and unnecessary, in my opinion.

d

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Answer 3

poikkeus1

Level 4

2,454 points

Nov 24, 2015 8:18 PM in response to fivepyelane

a brody makes a good point, but what qualifies as "intolerable" is different for every user. But these temps are perfectly normal.

Perhaps you could describe the objectionable sound, or how it sounds relative to other Macs you've tried.

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Answer 4

fivepyelane Author

Level 1

0 points

Nov 25, 2015 5:29 PM in response to poikkeus1

I agree that the temps seem well within tolerance. We've had the computer for 4 years and it's never gone full throttle on the fans in my memory. Now it's full throttle all the time, even when the computer has been put to sleep. The air emitted from the top vent feels like room temperature (though I didn't measure). Even my 72 yo nearly deaf father said that he thinks something is wrong with the computer because it's "making a really loud noise." "Intolerable" is generous in my opinion, but, factually speaking, it's 12 to 18 dB louder than it's ever been (and yes I own an SPL meter). The noise seems to have started around the time we upgraded to Yosemite if that gives anyone a lead. I am going to try to start up using an external drive with mavericks on it to see if the computer calms down.

Thanks again for all your help.

Happy Thanksgiving!

d

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Answer 5

den.thed

Level 9

77,158 points

Nov 25, 2015 6:12 PM in response to fivepyelane

Sounds like maybe either a hardware problem with a sensor or something within that temperature utility that you are using.

1. To check your Mac for a bad sensor, see > Using Apple Diagnostics - Apple Support

2. I'm not sure what utility you are using to get that Sensor Overview shot, but many come with a couple of different way to set and/or adjust the fan speeds. If so, then perhaps you have accidentally done something within that utility that has caused a fan or all the fans to run at full speed.

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