We're Always Open Call Us Today!

How Do I Troubleshoot My A/C System?

“How do I troubleshoot my A/C system?” – It’s  a questions we get asked a lot.

So it’s the middle of summer, it’s sweltering outside … and your air conditioner decides to stop functioning.

Before you panic and call a HVAC professional, there are some basic steps you can take to troubleshoot your A/C in case it is just a simple fix that you can do on the spot.

And even if it turns out to be something you can’t fix, doing a little checking and testing in advance can save time when you call an HVAC technician out.

1. Check The Power

Though it seems almost too obvious to state, if the unit won’t even power up, the most common reason by far is that electricity is somehow not getting to it.

You’ve likely already thought to check that the unit is plugged in, but you should also check that the outlet itself is still functional (using a simple and inexpensive plug-in tester that can be purchased at any hardware store).

If the outlet is good, check the circuit breaker it is connected to, as the high amount of power used when the air conditioner comes on frequently causes them to trip.

If it’s an outside unit, there should also be a hardwired disconnect switch inside of a metal box somewhere close to the unit that may have been flipped on.

2. Check The Filter

Some units will actually manually shut down if they detect that the filter is blocked and that a normal level of air is not getting through.

It’s worth pulling the filter out and taking a quick look to ensure that a clog isn’t causing your problems.

3. Check The Ducts

In larger systems, the supply and return ducts have registers that can become clogged, or can simply be manually closed by mistake.

These are the grilles that you will see that are most commonly mounted on walls, in floors or on ceilings.

Commercial registers also often have dampers attached that will automatically shut if they detect smoke or an unusually high level of heat.


These basic steps should tell you if you’re dealing with a simple fix or something that requires professional attention.

If you’re A/C isn’t working and you’ve asked “How do  I troubleshoot my A/C”, followed our advice, and still don’t have working air conditioning, then contact us at 651 294 7798 for a free estimate and worry-free service.

Schedule a HVAC repair anywhere in the Minneapolis or St. Paul area today by calling (651) 294-7798 or by requesting an estimate online.


Contact Us

1220 Cope Avenue East, Maplewood, MN 55109