Why is My Air Conditioner Not Cooling the House?

Once summer hits, you want your central air conditioning ready to go. But, what happens when you turn it on, and it’s not cooling the house?

In this article, we’ll look at some of the most common culprits when your air conditioner doesn’t cool down your house once you turn it on. Two of them are simple fixes you can handle yourself. The second two require a professional. But, at least you’ll have an idea of what’s happening.

Four Reasons Your Air Conditioner is Not Cooling the House

The four most common reasons for your air conditioner not to cool the house are:

  1. Air Filter is Clogged
  2. Thermostat is Set Wrong
  3. Coolant is Leaking
  4. Lines are Damaged

Air Filter is Clogged

How often do you change the air filter in your HVAC system? If the answer is any more than three months (or, “What’s an air filter?”), this may be your problem.

The filter is that cloth screen that traps dust, dirt, debris, and other particles as it passes through your forced-air system. This way, that stuff doesn’t keep circulating through the air in your house.

But, if you don’t change it often enough, the filter gets clogged, and then not even air will pass through it properly.

That would mean your AC turns on in the summer, but no air comes through the vents. The pressure isn’t strong enough to push through the clogged screen.

Pull out the filter. If it’s dark grey, it’s been in there way too long. Replace it immediately and see if that solved the problem. After that, your best bet is to change it every month if you can.

Thermostat is Set Wrong

Most thermostats have three basic settings: Heat, Cooling, and Fan Only (or Circulate). It’s that last one that usually trips people up.

When you set it to Fan Only, you’ll hear the system kick on. But, you won’t get any air conditioning— or heat, for that matter.

All it’s doing is circulating air through the house. It’s useful during the shoulder seasons when it’s too chilly to open the windows, but you want to get rid of that stuffy feeling.

If you set it to this by accident or forget you had it on that setting, you’ll get lukewarm air in the summer when you’re looking for the AC. Or, if you left it on “heat” for the winter, it may not turn on at all.

On “Heat,” it’s waiting for the temperature to dip below your setting before it turns on. And, of course, you want it to go the other way.

Coolant Leak

Now, we’re getting into the problems for which you’ll need to call a professional. And, depending on the age of your air conditioner, this is either a simple fix or the first step toward buying a new system.

Let’s back up a moment: The coolant, or refrigerant, is a crucial component here. It runs in a closed loop through the system, which means you should never run out. The same coolant keeps heating up and cooling down.

If you have a leak, however, you lose the refrigerant. When that happens, the air keeps passing through the system but doesn’t cool down.

Inside your home, you’ll notice the system working, but the air coming through the vents is not cool, and so the temperature in your home won’t drop.

If this is happening, check your outdoor condenser. If there’s a hissing sound and/or a sweet chemical smell, you’ve found the problem.

As far as repairs go, coolant leaks are simple enough: Find the leak, fix it, and recharge the system.

However, the old freon solution that older ACs use, called R22, is no longer in production. So, supplies are scarce and getting more expensive.

If you have an AC that’s more than a decade old, you may have to replace it: the cost to repair and then recharge won’t be worth it for a unit that doesn’t have much life left, anyway.

Lines are Damaged

With most of these problems, you’ll probably notice the condenser turning on. But, it’s not giving you the results you want. If the system won’t power up at all and set the thermostat correctly, then the lines inside or leading to the condenser may be damaged.

Remember, you’re dealing with a piece of machinery that’s outside. So, it’s susceptible to all kinds of damage, from weather to vandalism, or even lawn clippings, trash, and debris, or animals. A lot can go wrong here.

And, it’s not easy to figure out precisely what’s happened without professional equipment. And, it’s a bad idea to go poking around the electrical equipment.

Instead, do a visual inspection. Check if any of the wires you can see are frayed or broken. Also, look around for signs of animal nests or activity.

Finally, maybe the condenser powers on, but the fan doesn’t turn. It could be jammed. Don’t try to fix it yourself — if it suddenly starts working while you’re in there, you can get severely injured.

But, knowing what to look for can help you understand what’s going on, and give your HVAC tech a head start when he gets there.

Air Conditioner Repairs in Elgin, IL

If the air conditioner in your Fox River Valley home doesn’t keep you cool, call us here at Compass Heating and Air Conditioning Inc. for air conditioner repair in Elgin, IL and surrounding areas. We’ve got an excellent reputation, dozens of five-star reviews, and will make sure your home is comfortable again as soon as possible. Call (630) 504-8688 or click here to schedule an appointment online.