Macs Fan Control

The other day Diskwarrior warned me that the temperature of my Late 2012 iMac was too high and it could damage my hard drive. That is the first time I had seen that warning, believe it or not. So, I did some research into this issue to try to head off any problems.



Internal temperature problems have been an issue on Macs for years, especially Mac laptops. I did not know that my iMac model has had these type of issues, but when I did online research I discovered these temp issues were very real. But, the issue is what to do about it?

I checked some of the processes on my iMac using Activity Monitor, but was not able to discover any glaring issues. I have an app called xScan Solo (read my previous article) which monitors all your settings on your Mac. I booted it up and noted that the temp of the Mac was above Apple specs, the high for my machine is 38° C. Here is the xScan window:

It was running a little hot as you can see. Maybe that is just what happens to a 3 year old iMac.

In an effort to head this off at the pass I started researching apps that control the fans on your Mac. There are a few of them out there, I ended up using Macs Fan Control which has been around for many years.

Mac Fans Control

Macs Fan Control (hereinafter referred to as MFC) is a free app distributed by Crystal Idea. I downloaded and installed it. A Restart was suggested. Here is the main setup window for MFC:

It comes in “Auto” setup which runs your Fan or Fans at fairly normal speeds. If you wish to up the “low end” speed to increase your Fan use then click on “Custom”:

Just move the slider up to a speed that looks good to you (some experimentation is needed here) and click “OK”. Then let your machine run for a while and monitor. As far as I can tell MFC does up the fan speed and lower the temp of my iMac.

MFC has a few Preferences:

You can set the app to auto start and put an icon in the menubar and tweak a few other settings.


If you are having temp issues on your Mac you might try Macs Fan Control. It may be a solution for you. But, of course, there is always the Genius Bar at the Apple Store as a last resort.