Why Is My AC Running All Day? What Chamblee & Brookhaven Homeowners Should Know
If your air conditioner seems like it has been running nonstop lately, you're not alone.
August in Metro Atlanta puts residential HVAC systems through some of their hardest working days of the year. Between high outdoor temperatures, humidity, afternoon sun and the heat absorbed by attics and older homes, your air conditioner may run for much longer periods than it does during spring or fall.
For homeowners in Chamblee, Brookhaven and surrounding Atlanta neighborhoods, the important question isn't simply whether the AC is running a lot.
It's whether it's actually keeping up.
Long AC Run Times Aren't Always a Problem
One of the most common misconceptions about air conditioning is that a healthy system should turn on, cool the house quickly and shut back off.
During moderate weather, that may happen.
During an Atlanta summer, however, longer cooling cycles can be completely normal. Your HVAC system has to continuously remove both heat and moisture from your home. On particularly hot and humid afternoons, a properly sized system may run for extended periods while maintaining a comfortable indoor temperature.
In fact, an air conditioner that rapidly turns on and off every few minutes — known as short cycling — can sometimes be more concerning than one operating through a long cooling cycle.
The better question is:
Is the system maintaining the temperature you've asked it to maintain?
If your thermostat is set at 74°F and the home stays around 74°F or 75°F during the hottest part of the afternoon, the system may simply be doing its job.
If the thermostat is set at 74°F and the indoor temperature keeps climbing to 78°F, 80°F or higher, it's worth investigating why.
6 Reasons Your AC May Be Struggling to Keep Up
1. A Dirty Air Filter Is Restricting Airflow
This is one of the easiest things for a homeowner to check.
Your HVAC system needs a large volume of air moving across the indoor coil. A heavily loaded filter restricts that airflow and can reduce system performance.
During periods of heavy summer use, check your filter regularly rather than relying entirely on the calendar.
Also make sure supply registers and return-air grilles aren't blocked by furniture, rugs or other household items.
2. Your Outdoor Unit Can't Breathe
Your condenser — the outdoor portion of the system — is responsible for releasing heat removed from inside your home.
Leaves, grass clippings, vegetation and debris around the condenser can interfere with airflow.
Homeowners can safely keep the area surrounding the outdoor unit clear. Cleaning the actual condenser coil or opening the equipment cabinet, however, is better left to an HVAC professional.
3. The System Has a Refrigerant Problem
Air conditioners don't normally "use up" refrigerant.
If a system is low on refrigerant, there may be a leak somewhere in the refrigerant circuit.
Possible symptoms can include poor cooling performance, unusually long run times, ice developing on refrigerant lines or the indoor coil, and a growing difference between the thermostat setting and actual indoor temperature.
Simply adding refrigerant without determining why the system is low may not solve the underlying problem.
4. Your Home Is Gaining Heat Faster Than Expected
Sometimes the HVAC equipment isn't the entire story.
Attic insulation, duct leakage, aging windows, air leaks and direct afternoon sunlight can all increase the cooling load on a home.
This can be particularly noticeable in Atlanta's older housing stock, including many homes throughout Chamblee, Brookhaven, North Druid Hills and nearby communities.
Closing blinds or curtains during periods of direct sunlight, sealing obvious air leaks and maintaining adequate attic insulation can all help reduce the amount of heat your HVAC system has to remove.
5. The Indoor or Outdoor Coil Is Dirty
Your HVAC system depends on two major heat-transfer surfaces: the evaporator coil inside and condenser coil outside.
When either becomes significantly dirty, heat transfer can suffer.
That means the system may continue running while delivering less cooling than it should.
Coil condition is one of several items that should be evaluated during professional HVAC maintenance.
6. The System May Be Aging or Improperly Sized
An air conditioner doesn't necessarily need replacement just because it's older.
But compressors, motors and other components experience wear over time, and an aging system may not perform the way it once did.
Sizing matters too.
An undersized system may struggle during peak temperatures. An oversized system presents its own problems because it can cool the space too quickly without running long enough to adequately control humidity.
That's why HVAC replacement shouldn't simply mean installing the same tonnage that happens to be sitting there today. Proper equipment selection should consider the home and its actual cooling requirements.
Don't Try to Make the House Cool Faster by Setting the Thermostat to 60°F
Your thermostat isn't an accelerator pedal.
If your home is 80°F and you want it to be 74°F, setting the thermostat to 60°F generally won't make a conventional air conditioner cool the house any faster than setting it to 74°F.
It simply tells the system to continue cooling well beyond your desired temperature if it's capable of getting there.
Instead, select a reasonable comfortable temperature and watch what the system does.
Pay Attention to Humidity, Too
Temperature is only part of summertime comfort in Georgia.
A home at 75°F with well-controlled humidity can feel considerably more comfortable than a cooler home with excessive indoor humidity.
Your air conditioner removes moisture as it operates, which is another reason proper equipment sizing and airflow matter.
If your house feels cool but clammy, has persistent high indoor humidity, or you're seeing unusual moisture around registers or other areas of the home, the HVAC system deserves a closer look.
When Should You Call an HVAC Company?
Consider having the system professionally evaluated if:
- The indoor temperature continually rises even though the AC is running.
- Airflow from the vents has become noticeably weaker.
- Some rooms suddenly aren't cooling properly.
- The system repeatedly turns on and off after very short periods.
- You notice ice on the refrigerant line or indoor equipment.
- The system is leaking water.
- The outdoor unit isn't running when the thermostat is calling for cooling.
- You hear new or unusual noises.
- Your electricity usage suddenly increases without an obvious explanation.
And if the system is operating normally but running longer during the hottest Atlanta afternoons, don't automatically assume something is broken.
Sometimes a hardworking AC is simply a hardworking AC.
A Little Prevention Goes a Long Way During an Atlanta Summer
August isn't a forgiving month for neglected HVAC equipment.
Changing filters, keeping outdoor equipment clear, maintaining unrestricted airflow and having developing problems diagnosed before they become complete failures can help keep your system operating reliably through the remainder of cooling season.