AC Efficiency FAQ

Young girl looking up inquisitively.

Our HVAC technicians are answering the burning questions you have about the efficiency of your air conditioner.

What are SEER Ratings?

SEER stands for Seasonal Energy Efficiency Ratio (sometimes also referred to as Seasonal Energy Efficiency Rating). The SEER of your HVAC system directly relates to the “ratio of the cooling output of an air conditioner over a typical cooling season, divided by the energy it uses in Watt-Hours.”

The SEER can be compared to the miles per gallon in your car--it’s not a guarantee of how your system will perform day-to-day, rather it’s an indication of the maximum energy-efficiency your system has the potential to reach. Air conditioners with a higher SEER will increase the comfort in your home over the hot summer months. If you’re looking to upgrade or replace an older HVAC, look for a system with a SEER of 13 or higher for the best efficiency.

How Can I Tell If My AC Is Losing Efficiency?

These signs can help you know when it’s time to replace your system:

  1. Frequent repairs. HVAC systems have a long lifespan (on average an HVAC will last 15-20 years), but their efficiency will significantly decline after approximately 10 years. If your system starts needing repairs more than usual, it may be nearing the end of its life. It’s time to replace your system when the cost of the repairs equals or surpasses the cost of a new system.

  2. Higher energy bills. A spike in your energy bills could mean that your system is working harder to pump air through your home. This could be because of a clogged or dirty air filter, or because your system is simply too worn down to keep up with the demand your home is placing on it.

  3. AC is running longer than it used to. Longer cooling cycles result in your HVAC system using more energy to get your home to the desired temperature.

  4. Inconsistent temperatures. If your bedroom feels cool but you find yourself sweating in the living room, you may have leaking ductwork or a drafty window or door. However, this issue could also be a warning sign that your HVAC system is the wrong size for your home.

How Does a Dirty Air Filter Affect AC Efficiency?

One of the most important things that a homeowner can do to protect their home comfort system in-between regular maintenance is to simply change their air filter. Your HVAC technician recommends that you change your air filter every 30-90 days, or as needed for homes with pets and/or heavy reliance on their heating and cooling systems.

But sometimes, life happens and the little things (like changing your filter) can slip through the cracks. This could cause some issues with your home comfort system. Here’s what can happen, when you have a dirty air filter:

  • Reduced airflow: Air being forced through a dirty filter means less air will get through. This may also cause your equipment to run longer than necessary to maintain the desired temperature.

  • Excessive dirt buildup within the duct system: If the filter is dirty, everything past the filter is dirty too; which means you could be pumping your home full of dust, mold, and/or allergens.

  • Air quality issues: Dust, pet dander, pollen, and other indoor air contaminants can affect your family’s health and your ability to keep your home clean. This should be an especially serious concern for anyone with respiratory issues such as allergies or asthma.

  • Higher energy bills: The reduced efficiency of your home comfort system will cost you.

Will Setting Your Air Conditioner’s Temperature Lower Cool Your Room Down Faster?

You probably don’t have to use your imagination to be familiar with this scene: It is a hot day and Kiera has just returned home from work. Her living room is hot enough to fry an egg on the floor. She quickly goes the thermostat to blast the air out, turning the setting down to a chilly 60 degrees so the room will quickly cool down.

Unfortunately for Kiera, her air conditioner will cool the room down at the same speed no matter what temperature she sets it to. Turning the thermostat down to 60 degrees will not get your home to your preferred 72 degrees any faster than if you were to set the thermostat to 70 degrees. In fact, setting your thermostat lower to try and cool your home down faster will only increase your cooling costs and the workload of your HVAC system. A good rule of thumb to follow while setting your thermostat? Set your thermostat to whatever temperature you want your room to be. The room will reach that temperature and stay at that temperature. It’s just that simple!


Keeping your family cool is our responsibility. The experienced heating and cooling team at A-TEMP Heating, Cooling & Electrical can help you with any AC installation, maintenance, or repair needs. Contact our team online or call to schedule an appointment at (503) 694-3396 today!

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