My Air Conditioner Won’t Turn On! Troubleshoot Common Causes & Fixes

My Air Conditioner Won't Turn On! | AC Repair In Boise, IDOnce it starts getting hot outside, the last thing you want your AC to do when you turn it on is … nothing! Even in the spring, an air conditioner that won’t turn on makes your home uncomfortable.

And, of course, you’ll worry about what’s wrong and how much it will cost to fix.

The bad news is that there are more than a dozen reasons your air conditioner won’t turn on. It’s one of the most obvious and common signs of a broken AC

But the good news is that you can fix a handful of them yourself.

Many common AC issues don’t require any technical know-how for you to troubleshoot and solve. You don’t even need to be handy to handle them!

Of course, there are plenty of issues that require a professional — even when you can identify the problem yourself. So, it’s always a good idea to call your trusted contractor when something goes wrong.

But, before you call, go through our quick and easy troubleshooting tips first. With any luck, you won’t need to call us at all.

And, if you have any questions, or if the central air in your Boise Metro home still won’t work after following these steps, call Snowflake Air at (208) 205-9078.

Four Reasons Your AC Won’t Turn On (And What To Do)

  1. Thermostat Troubleshooting
  2. Clogged Air Filter
  3. Blown Fuse
  4. Refrigerant Leak

Basic Thermostat Troubleshooting

The wrong thermostat settings will prevent your central air from kicking on. It’s more common than you may realize: People often forget to change from the heating settings. Or, there’s a small problem that’s easy to fix.

What To Do

First, change the batteries if you haven’t done so in a while. Low power can affect the connection between this gauge and your HVAC system.

Next, make sure you’re set to “Cool” and “Auto,” not “Heat” or “Fan Only.”

On heating mode, your system waits for the temperature to drop. Then it turns on the heat.

You may hear the system kick on in Fan mode but get no cooling. That’s because this setting only circulates the air without treating it.

Clogged Air Filter

A Clogged Air Filter Is An Easy FixYour air filter traps dust, dirt, and other tiny particles as they pass through your ductwork. That prevents this stuff from clogging up your furnace and AC. But, eventually, the filter itself gets clogged.

When that happens, no air can pass through it.

That means no air enters your system to get cooled, and your AC won’t kick on. Or, the AC turns off and on over and over every couple of minutes.

What To Do

Remove the air filter. Is it grey or darker? If so, it’s likely clogged. Replace it with a new one and change it at least once a month whenever you’re running the heat or central air.


Blown Fuse

It’s rare but possible your electric box got overloaded the first time your central air kicked on. Now there’s no power going to the unit.

What To Do

Check the circuit box for any tripped breakers. If you see one, reset it and set your thermostat to “On” instead of “Auto.” This should cause the AC to go on right away.

If it turns on but then trips again, call your HVAC professional. Don’t keep resetting it.

Refrigerant Leak

Today’s systems are smart enough to know when there’s not enough refrigerant present for the system to do the job. If there’s a leak, your AC may never come on. 

You can’t fix a leaking air conditioner yourself. But, you want to catch it as soon as possible before the problem gets worse.

What To Do

Go outside to your condenser. Listen for any hissing sounds and check for any chemical smells. These are the signs that refrigerant is leaking out somewhere. If you notice this, call your HVAC contractor right away.

Clogged Condensate Line

As your central air dehumidifies your home, the water vapor it captures cools and turns back into liquid. A drain line, usually a skinny piece of PVC piping, allows the water to exit the system.

Sometimes, however, algae grows in the line and causes a clog. The same can happen if dust or dirt builds up in there.

When this happens, water backs up into the system. In some cases, it’s enough to trigger an error, and your unit won’t turn back on.

What To Do

Check for water leaking on or around your furnace inside. The cooling occurs in the coil inside there, so that’s where the water drains from. 

If you can access the line, carefully use a flashlight to peer inside it. If you can see a visible blockage, you’ve likely found the problem. 

We don’t recommend taking the line apart to clean it. You may damage it or put it back incorrectly. Then, you’ll end up with another leak or worse. 

In that case, the money you think you saved with a DIY fix ends up being a huge loss when you have to pay the much-higher cost of a new air conditioner installation.

Prevent Air Conditioner Problems With Regular Maintenance

Regular Service Is The Best Way To Avoid RepairsThe best way to avoid air conditioner problems like the ones we outlined here is with regular maintenance or a spring tune-up. 

Instead of waiting for something to go wrong (or worrying that something will happen), we can clean and inspect your system before it’s time to start using it. 

This way, you know everything is optimized and in excellent working order. If we do find anything that’s damaged or worn down, we’ll replace it before it causes a problem. 

It only takes about an hour in the springtime, and then you’ll be confident that your air conditioner is ready for the summer.

Along with that peace of mind, you’ll enjoy lower electric bills all summer. That’s because a well-oiled system requires less energy. And, a well-maintained system lasts for more seasons than one without any tune-ups. They break down less often, too.

AC Repair In Boise, ID

Snowflake Air has hundreds of five-star Google reviews and an excellent reputation for expert, reliable AC repair in Boise, ID and across the Treasure Valley. Homeowners from Caldwell to Kuna to McCall trust us to keep their homes comfortable all year long. Click below or call us at (208) 205-9078.