Q: My MBA is heating up very quickly.

The Apple article below may help.

Apps can affect Mac performance, battery runtime, temperature, and fan activity - Apple Support

Fortunately, you can test your machine using Apple’s online hardware testing facilities. If your MacBook Air was made prior to June 2013 you’ll use the Apple Hardware Test, and if it is more recent it will use Apple Diagnostics. Don’t worry though, they’re very similar and are accessed using the same method:

    Shut down your Mac and connect the power cable.

    Press the power button and then (before the gray startup screen appears) hold the D key.

    Select a language if prompted, then follow on-screen instructions.

If you’re using Apple Diagnostics on a recent Mac, you won’t need to do anything as the test will complete automatically. You should make a note of any error codes or other pertinent information, particularly if your machine is out of warranty and you will need to conduct repairs yourself.

If you’re using Apple Hardware Test on an older Mac, you will be prompted to either perform a basic test or a thorough test. The basic test should be enough to detect cooling problems.

Machines that shipped with Lion (OS X 10.7) or later will be able to send this information over the Internet to Apple, handy if you want to make a Genius Bar appointment (particularly if it’s under warranty).

Regards,

Talha