Air conditioner troubleshooting comes in two flavors: The easy stuff you can do yourself and the technical problems should be left to an experienced HVAC professional. The DIY version mainly involves ruling out the obvious things that might result in a wasted service call. You may encounter a simple fault you can fix yourself. But if not, you’ll end up scheduling a service call to repair the problem. Still, because you’ve at least ruled out the obvious potential problem yourself, after air conditioner troubleshooting, you’ll have more confidence in what the technician recommends.