Homeowner Articles What Happens If My AC Unit Is Undersized

The first thing anyone wants to do after spending all day in the hot South Carolina sun is to chill down in your home’s cool air. But if your AC unit is too small for your home, you may feel less than chill.

What happens if my AC unit is undersized?” you may wonder.

Read on as our Upstate Home Maintenance Services team examines how to tell if you need a bigger AC and what to do about it.

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Why Small Air Conditioners Cause Problems

Central AC and window AC units mounted to side of a building

The issue with undersized air conditioning comes down to BTU capacity. BTUs (British Thermal Units) indicate how much warm air an AC system can efficiently cool. 12,000 BTUs can eliminate one heat ton in a full cycle.

The higher the BTU, the cooler the house.

But while small, low-BTU AC units may cool a room or small apartment, they will struggle the bigger your home’s square footage is.

An undersized air conditioner won’t have enough power to keep your whole home cool if your house’s square footage is too large for the air conditioning’s BTU output.

An undersized AC unit can also lead to financial issues. An air conditioner works by cooling your home until it hits your desired temperature, but if it’s too small to hit that internal temperature, it will continue running and eventually overwork itself.

That wear and tear will break your HVAC system, and you’ll need constant repairs to make it through the grueling summer months.

How to Tell If You Have an Undersized Air Conditioner

Magnifying glass next to a model home

So, what happens if your AC unit is too small?

You’ll pay hundreds of dollars in AC replacement costs yearly from regular wear and tear, all for an AC that can’t adequately cool your home.

Luckily, there are several definitive ways to tell if your home has the wrong air conditioner size, from cooling quality to extra costs.

– If It Only Cools Small Rooms

All of your home’s rooms with air conditioning vents should be the same temperature, regardless of size.

However, the low airflow from small AC systems is only strong enough to chill tiny areas without much heat tonnage.

So if your small bedroom feels perfect, but you’re sweating in your spacious kitchen, your AC might be undersized.

Unfortunately, so many factors determine your AC’s cooling quality, including common issues like a failing condenser unit and a clogged air filter.

But if you take good care of your AC, your home’s temperature inconsistencies are likely an issue with the AC’s size.

– If Your Air Conditioning System Runs Longer than The Average Cycle

Most properly-sized air conditioners run on half-hour cycles to cool your home to the desired temperature.

But if your AC keeps going for longer than that average cycle, it likely doesn’t have enough strength to chill your house thermostat’s set temperature and needs to operate for longer than it’s designed to account for that cooling difference.

– If You Have Higher Energy Bills Than Expected

Your energy bill will spike if your AC has to run all day because it’s too small to cool your home on short, half-hour cycles.

Even though an undersized air conditioning system uses less power than an oversized unit while operating, a small AC’s extended run time takes up more power overall, leading to high energy bills.

Is an Oversized AC Any Better?

oversized AC in front of a home

So if small air conditioners aren’t fit for big homes, are you better off installing a new air conditioning system with too much power?

Unfortunately, an oversized air conditioner presents as many issues as an undersized one.

Oversized, big-box ACs cool homes quickly and have a short cycling schedule.

But that quick cooling forces them to turn off and on repeatedly, leading to detrimental wear and tear.

Installing an oversized new air conditioner also leads to poor air quality.

Because the air conditioner sits idle more often than perfectly-sized units, the air conditioning’s built-in dehumidifier can’t remove all the water vapor that builds within the system, leading to excess moisture in your home’s air.

Bring The Perfect Air Conditioner to Your Home

To summarize the answer to the question, “What happens if my AC unit is too small?” your home won’t cool, your AC system will constantly break, and you’ll have piles of extra expenses to manage.

But AC installation from our team at Upstate Home Maintenance Services will eliminate your undersized AC woes by bringing perfectly-sized, state-of-the-art air conditioning to your home for a competitive rate.

We can save you money on your power bills! It’s our best contractor success story.

Contact our team today for a free estimate. Call us in Spartanburg at (864) 529-7310 or in Greenville at (864) 210-8444.

This article was written by Morgan Loch

Owner of Upstate Home Maintenance Services LLC and Local HVAC Guru

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