Mac Studio
If your Mac fans seem to be coming on too often, or the fans are running at full speed and seem excessively noisy you might be wondering why and what you can do to fix this.
When you use your Mac the fans will engage as the Mac gets hotter, increasing in speed to bring in air to cool the device. If your Mac is working on multiple or intensive tasks, for example a video call with lots of participants, photo or video editting, you have lots of active internet tabs open, or indexing the hard drive with Spotlight after you migrate data - the fans will run faster to try and keep the device cool.
If your fans are running faster than expected here are some best practice tips and a process to follow to try and fix the issue.
1. Make sure the vents aren't blocked and the Mac can cool
Are the vents clear?
MacBooks have vents around the edges, these let the fans circulate air to cool the device. Make sure these aren’t blocked, for example with a case or keyboard cover.
Macs are designed to be used on a hard, flat surface. If you use your device on a soft surface like a couch, pillow, bed, or your lap, the device may not be able to cool.
How hot is your surrounding environment?
If you’re currently using your Mac whilst sat outside in the sun, bear in mind the fans will likely come on sooner. Macs are designed to function where the ambient temperature is between 10° and 35° C.
If you use third-party apps that measure the temperature of your notebook computer, it’s important to understand that they don't measure the external case temperature. For this reason Apple advise against this as the case temperature is much lower.
Fun fact, the new M1 MacBook Air doesn't have a fan! Swipe right to see a side by side with an Intel model.
M1 Air on the left (got no fans), Intel Air on the right
This will help you determine whether the issue is more likely software or hardware related. You can see step by step instructions to do this on Apple's site, here. There are specific error codes which let you know if there is an issue with the fan (PPF001, PPF003, PPF004).
If Apple Diagnostics returns ‘No Issues Found’ continue reading to see how to investigate software issues.
Apple silicon
- Turn on your Mac and continue to press and hold the power button as your Mac starts up.
- Release when you see the startup options window, which includes a gear icon labelled Options.
- Press Command (⌘)-D on your keyboard.
- Follow the on-screen instructions to run Apple Diagnostics
Intel
- Turn on your Mac and then immediately press and hold the D key on your keyboard as your Mac starts up.
- Release when you see a progress bar or you're asked to choose a language.
- Follow the on-screen instructions to run Apple Diagnostics
Most often the fans are responding to how the Mac is being used, more specifically the load on the CPU, GPU and memory.
Close apps you’re not using
As a first point of call I would scan your dock and quit any apps that are open that you don’t need. The open apps have a dot underneath, to quit you can click the app, then at the top click the app name, then select Quit in the dropdown. Professional / highly visual apps use a lot of energy, for example Adobe CC, Logic, Final Cut Pro, Parallels, AutoCAD and Zoom.
Close tabs you’re not using
One of my bad habits is having lots of active tabs open and this is most often what is using the majority of the memory (RAM) when I’m using my Mac. To reduce this load, close down tabs you’re not using and consider using Safari over Chrome. Visually heavy sites, as well as sites that refresh regularly are common culprits here, like Facebook, Twitter, Youtube, Google Sheets, Figma.
Use Activity Monitor
Activity Monitor is a great way to keep an eye on any processes taking up resources or malfunctioning. Open Activity Monitor from the Utilities folder of your Applications folder, or use Spotlight to find it.
Here you will see a list of current processes that can be sorted by the percentage of the resource that they are using, for example on the CPU tab you may find that Spotlight is taking up a disproportionate amount of %CPU whilst it carries out it’s initial indexing.
In the memory tab, if you have lots of internet windows and tabs open you might spot the browser you’re using listed numerous times. This will be reduced by closing tabs and windows down. You can also compare Memory Used against Physical Memory to see how much memory you have free.
A good way to find any processes that are using too many resources over time is by checking the Energy tab after using the Mac for a while, this is a good barometer for usage of all of the different resources.
Open Activity Monitor via Spotlight
When your system is acting sluggish or simply not responding, an app or process may be the source of the problem.
You can find out how much energy your Mac is using, and see which apps or processes are using the most energy.
If you have checked the above and the issue persists reset the SMC (link, here). The system management controller (SMC) controls how your Mac manages power. Resetting the SMC can resolve certain issues related to power, battery, fans and other features.
If there is an underlying software issue, the simplest way to fix this is by erasing your disk and reinstalling macOS - restoring the Mac to factory settings. Apple have a step by step guide to do this, linked here. Note, erasing the drive is irreversible hence you would need to backup ay data first you wish to keep.
