Can an old AC unit cause a high electric bill?

Author: Lizeth McGlynn DDS  |  Last update: Monday, October 13, 2025

An Aging AC Means A High Electric Bill If your AC is approaching 10+ years, then it may be time for a new AC. Just like your car, components within your unit experience wear-n-tear over time, causing inefficiency. Unfortunately, this means it takes more energy to cool your home.

Can an old AC cause high electric bill?

How old is your air conditioner? Newer models are designed using Energy Star requirements, so they use less power. Older models aren't, so they might use up more electricity in order to run. Plus, these older models are more prone to damage, leaks, and coolant issues, making them more costly to run overall.

Do old AC units use more electricity?

Not only do old AC units use more electricity, but a fairly new system can experience this issue, too. A lack of maintenance usually contributes to the increase in your energy costs and can even cause extreme mechanical problems. Don't ignore basic maintenance just because you have a new air conditioner.

Does an old AC unit cost more to run?

Your old air conditioner actually costs more to run, because it has a lower SEER (Seasonal Energy Efficiency Ratio). How much more? It can cost you 50 percent more and higher.

Do AC units make your electric bill go up?

Yes, running central air conditioning (A/C) in an apartment building will affect your electric bill. The A/C unit consumes electricity to cool the air, and the more it runs, the higher your energy usage will be. Here are some factors that can influence the impact on your bill:

My Electric Bill Skyrocketed! Let's Find Out Why | The Fixit Shed

Why is my AC using so much electricity?

Your AC system uses more electricity if some parts, like the capacitors, motor and condenser, fail. Further, your air conditioner will be less efficient due to too much strain on the functioning parts. If you don't address the issue, your system might experience a total breakdown.

How efficient is a 20 year old AC?

Today, the bare minimum is 9.7 for single-package AC systems and 10 for mini-split air conditioning systems. The AC SEER rating of a 20-year old air conditioner is therefore likely to be quite low, meaning it struggles to cool your home in an efficient manner and will use more energy than a newer model.

Should I replace my 15 year old AC unit?

14 to 20 years old: This is the average life span of well-maintained HVAC equipment. A breakdown at this age may warrant a replacement.

What is the average lifespan of AC?

While every unit is different, and every homeowner has a different understanding of when their central air conditioner is broken beyond repair, it's fair to say that, with proper maintenance and care, you can expect a good 15 to 20 years of cooling from a new high efficiency air conditioning system.

How inefficient are old AC units?

Repair: Older AC units typically have lower energy efficiency ratings (SEER), which means higher electricity costs. For instance, a 20-year-old unit may have a 10- or lower SEER. Replacement: New AC units are significantly more energy-efficient, with SEER ratings ranging from 14 to 25.

Does a bigger AC unit use more electricity?

Higher Utility Bills

A bigger unit simply gobbles more power than a smaller one. To make matters worse, your oversized air conditioner will likely never reach its promised level of energy efficiency. Just as it is cycling up to its most efficient level, the thermostat will tell it to shut off again.

When should I replace my old AC unit?

Replacement Age

If your unit is more than 10 years old, there are many factors that may encourage you to replace the unit. Energy Efficiency: Units that exceed 10 years of age do not meet the same energy-efficient standards as modern units. Warranty: Older units may no longer be covered under their warranty.

How can I lower my AC bill?

14 Ways to Reduce Air Conditioning Bills in the Summer
  1. Make room for fans.
  2. Shut curtains, blinds, and shades.
  3. Close off unused rooms.
  4. Program your thermostat or install a “smarter” one.
  5. Turn on a dehumidifier.
  6. Use a programmable power strip.
  7. Use natural ventilation.
  8. Service your A/C to reduce air conditioning bills.

Why is my AC costing so much money?

Your HVAC Efficiency is Low

During the hot summer months, HVAC systems have to work hard to cool the air inside the home and therefore keep everyone comfortable. If your energy bills shoot up as soon as you turn on the air conditioner, it could be that the efficiency of your HVAC system is very low.

How much electricity does an old AC unit use?

A 20-year-old air conditioning system might use 6 kWh of electricity to cool an average-sized house. A modern AC system could cool that same house using as little as 1.71 kWh of electricity.

Is it worth fixing a 20 year old air conditioner?

Air conditioner is over 15 years old

The typical lifespan of an air conditioner is around 15 years, at which time it must be changed. Some air conditioners may work well beyond their designed lifespan, but they become less efficient with time.

Will a new AC unit cool my house better?

Newer systems can regulate the temperature in your home more precisely than older models. A new air conditioner will use less energy to lower the temperature and when paired with effective insulation, will keep your home cooler for longer.

What is the best temperature for AC to save money?

According to the Department of Energy1, 78° Fahrenheit is the sweet spot for air conditioners to balance energy savings and comfort when people are at home and need cooling.

Is it cheaper to run AC all the time?

The short answer is yes, it's more cost-effective to keep your air conditioner on all day. However, don't take this as a green light to crank it up to the max 24/7! There's a smart way to go about it, which we'll delve into in a moment. So, why is it cheaper to leave your AC on?

Is it worth replacing the condenser on an AC unit?

Benefits of Replacing Your AC Condenser

Improved energy efficiency: A new condenser unit can reduce your energy bills and save you money over time. Increased comfort: A new system can cool your home more effectively, providing you with greater comfort during hot weather.

Why does AC make electric bill high?

The more your AC unit has to work, the more energy it uses up and the higher your average air conditioning bill will be each month. If you think you have leaking air ducts, schedule an appointment with your HVAC technician and let them inspect the system.

How much is a normal AC bill?

"But the average monthly cost for most people is anywhere from $70 to $144 a month in the summer." The type of cooling system in your home can also affect energy use, but not as much as you might think.

How much does it cost to run an air conditioner for 24 hours?

Air conditioners can cost anywhere between $0.32 and $1.87 to run per hour depending on the type and where you live. Investing in one or more fans for your home can be a great idea to keep your cooling costs down this summer. The upfront cost may be a bit higher but it'll pay itself in no time.

Previous article
How often should I clean my dishwasher trap?
Next article
Why does the bottom of my pan always burn?