Why isn’t my Central Air Conditioner Keeping Up?

Summers in Kansas can be quite rough. In just about a month from now it’ll be mid-July and we’ll have temperatures consistently above ninety-five degrees. In many cases we may see a week stretch of one-hundred plus degree highs. Besides the local swimming pool the only way we can escape these high temperatures is by retreating to our homes and relying on our central air conditioners to keep us cool.

But, what do we do on these crazy hot days when we realize our air conditioner just isn’t keeping up? We have it set to seventy-four but the thermostat reads eighty-two and the air conditioner hasn’t shut off for hours. In this article we are going to take a look at this exact scenario and figure out the cause behind it as well as taking a look at solutions to help your air conditioner do its job.

There are a variety of reasons that could cause your air conditioner not to be keeping up with your demand. I’m going to break this article up into three sections and take a look at each possible reason. Let’s dive in.

Record Heat

Every once and a while we get one of those insane heat waves where it seems it will just never end. It is day after day of one-hundred plus degree days. It’s miserable. It may be hard to keep these days in perspective as you are living through them, but you have to realize that these extra hot days are the exception. In most cases your air conditioner isn’t designed to withstand such hot temperatures. If you find that it’s one-hundred and six degrees outside and your air conditioner isn’t keeping up… don’t get mad at it! It is most likely working fine; it just wasn’t designed for the punishment of one-hundred degree temperatures.

The air conditioner for your home was made with a specific designed temperature in mind. As an example, let’s say you live in an area where it very rarely gets over ninety-five degrees. Maybe this only occurs a few days a year. It would make sense then to have an air conditioner that is designed to handle ninety-five degree temperatures.

So, if you have a heat wave of constant one-hundred degree days in the middle of August then your air conditioner is not going to keep up. Remember, it is not designed to handle those kinds of temperatures. You will find that most every other air conditioner in your area is having the same problem.

You see HVAC Contractors install air conditioners based off of the climate they are in. So, you would get a different air conditioner if you live in Phoenix compared to Boston. These are two distinct climates and require two distinct air conditioners.

Sure, you could get a ‘Phoenix’ air conditioner for your New England home but it’s going to cost you a lot and it may not even be worth it. I mean, why pay extra for that little bit of extra comfort for a few days out of the year? Soon enough the heat wave will dissipate and your air conditioner will return to normal functionality.

Air Conditioner Problems

If you are experiencing a record heatwave then I wouldn’t say that your air conditioner has a problem but more so that it’s just overloaded. This is the scenario that we discussed in our first section, ‘Record Heat.’ However, if you find that your air conditioner isn’t keeping up and it’s not that hot outside. (Under ninety degrees) Then you may in fact have a problem with your air conditioner.

There is a whole host of reasons of what could be causing your air conditioner to lag behind your demands on a moderate day. I won’t get into every possible reason here but instead direct to you an article that I wrote a few days ago titled, ‘Why Isn’t My Air Conditioner Cooling My Home?

Along with the reasons mentioned in our linked article above there is another possible reason why your air conditioner isn’t keeping up with your thermostat. It could be as simple as your air conditioner is too small for your home. You may have a three ton system installed and in actually need a five ton. If this was the case then it would result in your air conditioner running constantly and never fully catching up to your home’s cooling needs.

If you suspect this is the case for your air conditioner I would recommend calling a service technician to inspect your air conditioner and see if it is in fact too small for your home. The downside here is that if this is the case then you’ll either have to stick with the air conditioner you have, supplement your cooling with portable/window air conditioners, or purchase a whole new larger central air system.

Heat Proofing Your Home

During these heatwaves your air conditioner is going to need your help. There are some things that you can do to keep your home cool and take some stress off of your air conditioner.

We’ll start with the basic ones and then work our ways up towards the more complex. First, you should ensure that you have all of your ceiling fans on and running. Along with the ceiling fans it would help to have standalone fans as well. We have one room in our house that just doesn’t seem to get cool no matter what we do. The other day we added a fan and kept it on at medium all day. The temperature difference has drastically improved. Sometimes it can be as simple as just adding a fan.

There are all kinds of ways for heat to get into your home. The most impactful though can be your windows, especially your south and west facing windows. In the days of extreme heat these windows can act almost like a greenhouse and actually amplify the heat it’s sending into your home. In order to prevent this most folks close their shades and curtains throughout the day. I have blackout curtains installed in my master just to ensure none of that heat gets in there.

However, if you find that you don’t like living in a cave with no natural light coming in you can invest in what’s called a Solar Shade Screen. These screens actually block a large portion of the sun’s rays. (Up to seventy-five percent.) You order them in a spool and they can then be cut as needed to fit across your screen. Many users see a reduced temperature in their rooms after installing and they don’t have to have the curtains or blinds drawn all day.

The next big step in reducing heat into your home is going through and identifying all of the air leaks. Air leaks can be everywhere throughout your home. Starting off, it would make sense to check every one of your windows and caulk them if necessary. Along with the windows you should also check your dryer vent. In a lot of cases warm air can sneak in through this.

Besides windows and the dryer vent you should be checking two other prime areas: Your basement/crawl space and your attic. Typically the basement/crawl space isn’t as big of a deal during the summer as heat rises, but it is still good to check and it’s one less thing you have to do when winter comes.

The attic though is the big one. That is where most of heat is getting into your home from. The first thing I would do is check the door to your attic. How warm does it feel? Does it feel like heat is coming through? If so, then you have already identified some of the problem. Check the seams around the door and caulk what you can. Then, go up into the attic and check the insulation levels.

When you close the attic door take a good look around the attic. Are you able to see light from your main floor peeking through? If so, then this isn’t a good thing! That means you’ve got air flowing through. If possible caulk these holes up the best you can. This may mean working around obstructions like vents or ductwork found in the attic. Please be sure to exercise caution while in the attic as you don’t want to make a wrong step. You could sending yourself through the celling by mistake.

Once you have sealed all of the holes that you have found it is time to take a look at the insulation. How much is there? Are you able to see any bare spots? If so, then you will need to add additional layers.

When the insulation has been laid, the holes sealed, and the other steps we mentioned above you should see an improvement in the temperature inside your home. Obviously, this depends from home to home. I’ve seen some reports of a couple degrees difference and others of only a slight improvement. It all depends how your house is to start. If you’ve got leaking air everywhere then yes, of course, you’re going to see an improvement.


A lot of folks get concerned when they see that their air conditioner isn’t keeping up with what temperature they have set on their thermostat. Right away they get nervous and then call their air conditioner technician to come take a look. I am hoping though, that after reading this article you feel a bit more confident on why your air conditioner isn’t keeping up and that in many cases it isn’t the end of the world.