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Air Conditioning Checking

How to Tell If Your AC Unit Is Too Small for Your House

Updated: Feb 10, 2023

Whether you’re buying a home or building one, the HVAC system is a special point of concern for most homeowners. The quality of your HVAC system will probably make the biggest difference in your day to day happiness with your home.

Do you have a sneaking suspicion that something is up with your HVAC system?

If you’re not happy with how your AC is performing, read these three signs that your AC might be too small for your home.

AC Unit in House

#1. High Electric Bills

Were you sticker shocked by your last electric bill? The first sign of real trouble with their AC systems that most homeowners get is from their power company! Ask friends with similar home sizes to you, preferably who use your same power company, what they pay every month for electricity. If you have several months in a row with a $300, $400, or even $500 power bill – your AC might be too small.

#2. Your House Never Gets Cold

The surest sign of an undersized air conditioner is if you struggle to get your home under 79 degrees. AC units used to be designed to take a space from incredibly warm to incredibly cool in one long, continuous cycle. Today’s air conditioners are designed a little bit differently than air conditioners of yesterday. Now they’re meant to cool your house slowly over time.

It’s more about keeping your air at a constant temperature and making small adjustments, so it’s normal for a modern air conditioner to be a little slow when taking your home from very hot to cool. But at a certain point, if you’re finding it’s impossible to consistently or easily keep your home below 79 degrees then an undersized AC unit may be the culprit.

#3. Long AC Cycles

Again, there’s a fundamental difference in the design of today’s AC units and the design of AC units in the past. It was not uncommon for air conditioners in the 50’s and 60’s to run most of the day, if not all day. A significant design change came in the 1970’s with the energy crisis which directed manufacturers to modify the way they made HVAC units, according to the US Department of Energy. Modern air conditioning units instead are designed to cycle for a shorter period, but more frequently.

Does your air conditioning regularly cycle for longer than 30 minutes? Even in the warmest areas of the country like Florida and Texas, an appropriately sized air conditioner should not cycle for significantly longer than 30 minutes. If your AC is consistently running all day, you may have an undersized AC unit.

Basic Air Conditioning Cycle

In a typical air conditioning cycle, your AC system pulls in warm air and evaporates, compresses, and condenses the air. This process cools the warm air. The cool air is then dispersed throughout your home, while your AC system pushes the remaining warm air outside.

If you suspect that your air conditioner is undersized, there’s a quick equation that “old-school” contractors use to find the recommended tonnage for the home.

Schedule Your Free AC Installation Estimate

If your AC is too small for your home, then get in touch with an HVAC professional right away! Give Energy Air a call today, or schedule an appointment online, and we’ll help you replace your undersized air conditioner.

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Whether you need a single air conditioning unit installed or a complete air conditioning system retrofit, our team of HVAC experts will handle it. Have questions or would like to discuss your project? Give us a call today to talk to one of our friendly team members, or schedule your appointment online.

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