You are in Georgia. Visit Alabama. Visit Tennessee.

You are in Georgia. Visit Alabama. Visit Tennessee.

You are in Georgia. Visit Alabama. Visit Tennessee.

You are in Tennessee. Visit Georgia. Visit Alabama.

You are in Tennessee. Visit Georgia. Visit Alabama.

You are in Tennessee. Visit Georgia. Visit Alabama.

You are in Alabama. Visit Georgia. Visit Tennessee.

You are in Alabama. Visit Georgia. Visit Tennessee.

You are in Alabama. Visit Georgia. Visit Tennessee.

How Long Should It Take to Cool My House Down With a Central AC?

How long it takes for your home to cool down depends on a multitude of factors:

  • How hot is your home when you turn on the AC?
  • How big is your house?
  • Is your attic insulated?

Without a professional inspection of your unit or house, it’s difficult to answer that question with 100% accuracy.

But for those of you skimming for a quick, generic answer: if your AC runs constantly without reaching your set temperature, something is wrong.

If your home never reaches the desired temperature, we suggest first checking the outdoor temperature.

Is it super hot outside? If so, this may be your issue.

Not particularly hot? We’ll go over 4 other issues that may be causing your AC to struggle.

First, though, let’s take a look at why your AC struggles on hotter-than-normal days.

High outdoor temperatures slowing your AC down?

If you live in the Atlanta, GA or Birmingham, AL area and it’s hotter than 93 degrees outside, chances are your AC is just a bit out of its league.


Well an air conditioner is designed to be most efficient when operating within the city’s “design temperatures.”

Design temperatures were calculated by engineers at ASHRAE and are the outdoor temperatures that your geographical area stays above and below for 99% of the year.

For example, for 99% of the year Atlanta’s temperatures stay above 23 degrees and below 93 degrees.

When outdoor temperatures exceed those numbers, your AC will struggle to reach the set temperature because it wasn’t designed to remove that much heat.

Instead, your thermostat will stay about 2-4 degrees over the set temperature.

The good news is that there’s most likely nothing “wrong” with your air conditioner. It’s definitely working harder than normal. But as long as you’re within a reasonable few degrees from your set temperature, there’s no reason to replace or repair the system. Try closing all curtains or drapes to keep out heat instead; this makes a big difference.

High temperatures not your issue?

If your AC is struggling to cool your house even in mild temperatures that fall within your design temperatures, your AC system might have an issue.

Other reasons your AC isn’t cooling down your home include:

Your refrigerant levels are low.

Refrigerant is a liquid in your AC that absorbs heat. So if your AC is low on refrigerant, it’s not able to absorb enough heat from your home.

And the most common explanation for low refrigerant levels is a refrigerant leak.

Not sure if this is your problem? Check out our article, “Refrigerant: 4 Signs Your Air Conditioner is Low”.

Solution: If a refrigerant leak is your problem, have a professional find and repair the leak and then recharge your system with more refrigerant.

Your air filter needs to be replaced.

A clogged or dirty air filter decreases the amount of air that is pulled into your AC system.

Solution: Replace your air filter regularly to prevent this.

Your AC is too small.

If your unit is too small for your home, it most likely struggles to keep your home comfortably cool even while running constantly.

Solution: You’ll want to replace your unit for one that is the proper size. Make sure you have a professional perform a Manual J Load Calculation beforehand.

You have leaky ductwork.

According to Energy Star, about 20 to 30% of cool air is lost to leaky ducts.

Leaks in your ducts means cold air is escaping into unconditioned places like your attic or basement instead of blowing directly into your house. That loss of cold air means your home will take much longer to cool off, even during mild weather days.

Solution: Have a professional inspect your ducts and repair any leaks.

Need help figuring out why your AC takes so long to cool your home? We’re here to help.

Are you in the Atlanta, Nashville or Birmingham, AL area? Contact us today to schedule an inspection and we’ll get you on your way to a cooler summer pronto!

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