AUSTIN TEXAS AIR CONDITIONING REPAIR - REPLACEMENT - SERVICE
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The Difference Between Low and High Efficiency Air Conditioning

Things sure do get hot here in Texas! With the temperatures outside rising, you want your home to be as cool and comfortable as possible.

There are so many AC options on the market today, it can be difficult to decide what's best for you and your family's needs.

With the increased awareness in energy conservation throughout the US, the Department of Energy has been encouraging homeowners to install the most energy-efficient air conditioning system they can afford – but are these new energy efficient units the best choice for your comfort?

How is efficiency in AC systems measured?

The cooling efficiency of AC devices is recorded as a SEER rating. SEER stands for Seasonal Energy Efficiency Ratio. It is the “miles per gallon” rating for AC systems. A higher SEER rating means a more efficient system. The Environmental Protection Agency requires all brands of air conditioning systems to have a SEER ratio of 14 or higher, (since January 1, 2015). Some modern cooling systems have earned up to a rating of 26 SEER and some specialty systems higher than that.

Generally speaking, the older your air conditioner, the less efficient it will be. Technology has advanced since your system was installed, raising the bar for what is considered “high-efficiency”. As your system ages and the more it gets used, the less efficient it will run – this is due to regular wear and the build up of dirt and debris on indoor and outdoor coils, the blower, etc.

Maintenance plays a role here, too.

If you have your system inspected and maintained regularly, it will be much more efficient than if you just ignore it. If you don’t maintain your system, it will likely reach that “end of life” point faster. The bottom line is that lower efficiency systems will cost more to run on a day-to-day basis and all central systems should be kept in top operating condition by way of quality periodic inspections and maintenance.

Think of AC efficiency like this:
How efficient is your air conditioner at turning your hard-earned dollars into cold air? The more efficient, the better! Just about any system will deliver cold air, but at what cost?

How can I make my current AC more efficient?

Basic maintenance and upkeep will help keep your AC unit working as efficient as possible. A few things to keep in mind:

Air conditioning systems must have a decent airflow to work properly. Anything that gets in the way of your AC system getting the air that it needs will reduce efficiency and performance by putting undue load on the motor and restricting air from traveling across the evaporator coil (the cold part!).

  • Airflow and your outdoor unit: Keep outdoor units clear of plants and overgrown weeds. Your AC needs to push all that hot air somewhere! You'll find your radiator fins work like a car radiator – if the radiator is blocked, the unit will have to work harder to produce that cool air you crave. The harder the unit has to work, the more it will cost to run and the more poorly it will perform.
  • Preventative maintenance: Get it serviced regularly. It's recommended to get your AC serviced at least once a year. This is no different than your car or your body; things need to checked out regularly to catch problems early. If an AC system isn't maintained properly, it gets dirty – REAL dirty! If it's not serviced, your AC can get full of hair, dust and debris and can even become a ripe environment biological growth. This can affect the air you breathe. The inside coils can even develop rust, and this can be blown through the plenum to every room in your home. This is a potential hazard for asthma/allergy sufferers and your health in general, but it's also bad for your A/C system too. When you get your annual service, the technician should clean the outside condenser coil and inspect the rest of the system for further maintenance needs. Getting everything looked at, cleaned and maintained properly will go far to help your A/C system run more efficiently, cool your home better and last longer.
  • Change your filter regularly: We can’t stress this enough! PLEASE change your filter regularly! When you don’t change your AC filter, your central unit gets less airflow delivered to it. Try running up a hill with your mouth covered… it's no fun. Reduced airflow means your AC has to work harder to get the temperature you want. This added pressure to the system can lead to your evaporator coil (the part of your AC that actively cools the air) to freeze up – stopping your system from operating properly and potentially causing some very expensive issues to repair!
  • Fix leaking ducts: A leaky duct could lose up to 30% of that sweet, cool air before it even reaches the room you’re in! Stop pulling hot, humid air from the attic or, worse, paying to air condition it!
  • Replace components when they start failing: Get a pro to replace failing capacitors or other components that aren’t working properly as soon as possible. If your A/C has parts that aren’t functioning at their full potential, it can cause other (more expensive) parts to work harder and fail sooner than expected, raising your costs considerably. If your service technician suggests replacing capacitors, don’t wait until these components completely die – this will cause the system to stop working completely and can damage expensive components in the meantime. Don’t forget – Murphy’s Law tells us the system failure will happen on the hottest day of the year, often on a holiday when you have family or friends in town! Be proactive.

Why are high efficiency air conditioners better?

Higher efficiency systems are newer systems that outperform their predecessors because they have taken advantage of changes in technology. The best of these systems operate with exceptional variable compressors that help maintain the optimal comfort level by turning on and off as little as possible. The key to your home comfort lies inside the indoor variable speed blower, the outdoor condensing unit and the intelligence of the controller, or thermostat. The compressor on today’s highest efficiency AC systems can variably control the flow of refrigerant and airflow going through the system, meaning you get the capacity you want when you need it, nothing more or less.


This chart illustrates how the temperature in your home is maintained with a minimal amount of energy being spent to keep the temperature consistent over a long period of time. Cycling on and off, not only puts wear and tear on your system, it takes many large bursts of expensive energy to… not really keep your home consistently cool.

Your existing AC system may be 15 to 20 years old. A lot of efficiency improvements have taken place during that time. Those advancements make high-efficiency systems cheaper to run because they are more effective at turning hot air into cold air. Due to the advancements in design and technology, today’s AC systems are more efficient than ever before. Using less energy makes them better for our environment too.

It's definitely worth considering investing in a newer, more efficient air conditioner for your home – benefits of newer AC units include:

  • They’re less expensive to run: by being more efficient at turning hot air into cold, your energy bills are significantly lower
  • Variable speed adjusters: Many high efficiency air conditioners are now equipped with variable air speed adjusters – giving the system more control over efficiency, performance and occupant comfort. The Carrier Infinity 20 has load matching performance with speed ranges between 40% and 100% capacity.
  • Media filters for better filtration: High-efficiency media filters are 4-inches or more thick and have more surface area due to their accordion-style design. This means the air that circulates through your home is actually a lot cleaner and less dirt makes it into your AC system.
  • Optimal humidity and temperature controls
  • Sound reduction as low as 58 decibels* in some models due to compressor sound blankets and upgraded fan blades.
  • Continuous blower system: A major bonus of installing a high efficiency, variable capacity (multi-stage) AC is the more continuous nature of air circulation. Rather than the irritating on/off cycle of older, less efficient single-stage models, this approach helps regulate humidity and helps to reduce random bursts of cold air. Without having to constantly restart, a high efficiency air conditioner is considerably quieter than their low efficiency alternatives.This move away from the on/off cycling also means there's less wear and tear on the AC unit motors – reducing the risk of early breakdowns.

Are high efficiency air conditioning units expensive?

Although they may cost more in the short term, high efficiency ACs end up costing less in the long term. They cost less to maintain, they last longer, and they use less electricity. But like buying anything new, you need to weigh up the investment, the length of time you will remain in the home and the savings you will see on your energy bill. Your comfort advisor can help you work through this so that you can weigh up your options.

Investing in a quality AC system is a critical part of maintaining your home and creating a comfortable space for your family to live. Spending a little more on a better model now can save you money in the long run, provide you a greater return on investment, and keep you and your family comfortable in your home.

If your current AC system is struggling to keep your home cool, call McCullough Heating & Air Conditioning to come out and investigate what's causing your AC to struggle.

Contact us today and we can send an expert technician to your home to diagnosis your problem, fast!

You may also be interested in reading How to choose a contractor to install your new AC system, and The Importance of Proper AC System Design. The design (component choices), installation and fine-tuning of your new system can make or break the performance.

* Proper sizing and installation of equipment is critical to achieve optimal performance. Split system air conditioners and heat pumps must be matched with appropriate coil components to meet ENERGY STAR criteria. Ask your contractor for details or visit www.energystar.gov. Quietest size within each model group during most common operating condition.

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